# Lightest XC Racing tire???



## mtbaiker (Feb 15, 2010)

Looking for a lgihtweight fastrolling tire... Please help!:thumbsup:


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## B.Trimble (Oct 26, 2011)

Maxxis 285 = 285 grams


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## bholwell (Oct 17, 2007)

B.Trimble said:


> Maxxis 285 = 285 grams


285 grams _*or less*_

There is no "over" in the acceptable weight tolerance for the MaxxLite 285.

BTW, there's also a 29er version: the MaxxLite 29 at 345g


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## sfer1 (Feb 22, 2009)

He asked what's the lightest XC Racing tire, not the lightest "only good for the pictures" tire.


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## irishpitbull (Sep 29, 2011)

Racing Ralph 2.1 Mine came in a 492g and 497g. Awesome tires.


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## B.Trimble (Oct 26, 2011)

dry conditions? or soft/muddy? dry Maxxis. soft/muddy Geax brand


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## waterxracer585 (Apr 18, 2006)

Maxxis Aspen / Kenda Karma Not the lightest ever, but light and good in most conditions hands down!


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## bholwell (Oct 17, 2007)

sfer1 said:


> He asked what's the lightest XC Racing tire, not the lightest "only good for the pictures" tire.


That's a pretty myopic opinion. To say that the MaxxLite is unsuitable for cross country racing is inaccurate. On the right course (smooth hardpack with very little loose-over) I think you'd be hard-pressed to find something faster.


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## Rod (Oct 17, 2007)

waterxracer585 said:


> Maxxis Aspen / Kenda Karma Not the lightest ever, but light and good in most conditions hands down!


I'm running the Karma on my bike and I like them for about any condition. They grip and are pretty fast.


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## mmoen (Jun 19, 2009)

Best light and durable is the bonty 29-0 weighs 410 grams and lasts a long time in dirt if you ride them on the road they wear out quick.


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## OLx6 (Feb 5, 2011)

Someone has to suggest it.

I love my Conti Race King 2.2 Supersonics.

480 grams
big volume
good all around grip
very fast
good wear with the black chilli

This is a great race tire


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## biffhamilton (Jun 15, 2009)

OLx6 said:


> Someone has to suggest it.
> 
> I love my Conti Race King 2.2 Supersonics.
> 
> ...


That's the tire I run as well. I just don't like it in the front. I'm on the east coast, and need something with a bit more side knob. Last season I ran a race king 2.2 tubless in the back and a 2.1 Nevagal in the front.

I need something lighter, but with better grip up front this season. I'm thinking a Rocket Ron.

Advice anyone?


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## RaveOn (Dec 21, 2003)

I too have been running the Conti Race King 2.2 SS and mine came in at 472g. While I do love this tire, I too have been searching for a better front grip lately and wanted a true tubeless ready tire.

I just bought a pair of RaRa 2.25 (EVO) as pictured below (more side knob). Not the lightest but a good compromise.


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## B.Trimble (Oct 26, 2011)

biffhamilton said:


> I need something lighter, but with better grip up front this season. I'm thinking a Rocket Ron.
> 
> Advice anyone?


I wouldn't use Rocket Rons. The Maxxis 310 was better for me. Geax Gato :thumbsup:


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## B.Trimble (Oct 26, 2011)

bholwell said:


> That's a pretty myopic opinion. To say that the MaxxLite is unsuitable for cross country racing is inaccurate. On the right course (smooth hardpack with very little loose-over) I think you'd be hard-pressed to find something faster.


Agree. A very fast tire.:thumbsup:


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## realconspiracy (Jan 22, 2011)

Kenda Karma 2.0. Great in the mud and fast in the dry too. 480g


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## Electric Panda (Jan 8, 2006)

Some of you guys may want to catch up on the science of what is a fast tyre for off road. Wide high volume and low pressure has less rolling resistance ie faster... than light but narrow low volume and high pressure.

An interesting link came up over in the 29er forum in a ye olde 26v29 debate. Science is somewhat dismissed over there sometimes but this is worth looking at in an XC race forum.
A reasonable study was done by Peter Nilges on tyre volume and pressure and the effect they have on rolling resistance. It is a little old but still relevant and the link is here http://www.mtbonline.co.za/downloads/Rolling_Resistance_Eng_illustrated.pdf

The short story is that the test he devised took 3 different widths/volume 2" to 2.4" (Approx Volume of a 26x2.0 tyre is 4205cm^3 and a 26x2.4 is 6055cm^3) and 4 tyre pressures from 1.5bar to 4bar (21 psi to 54 psi) and tested these to consider rolling resistance on different surfaces - gravel, grass and tarmac. Carcass flexibility is also discussed.

Tyres on a 29 wheel are often cited as better rolling because of the higher volume which gives a bigger contact patch, comfort and rolling efficiency due to less sidewall deformation and lower PSI availability than the equivalent width tyre on a 26in wheel. For example a 29x2.25 tyre has an approx volume of 5935cm^3 versus a 26x2.25 volume of 5309cm^3 (Volume will change for different rim widths and profiles but not greatly)

The Nilges study concluded that the higher volume tyres do indeed roll better due to a bigger more conforming contact patch and less sidewall deformation. When high volume tyres are used at lower pressures ie 21psi then efficiency is increased yet again. He gives wattage figures but with no context it is difficult to ascertain a percentage advantage figure. 5935cm^3 eg 29x2.25 or the larger volume 26x2.4 (6055cm^3) can generally be run at these low pressures without rim damage. Of course there is a weight/mass penalty to some degree. Obviously similar volume tyres of similar construction will be a similar weight whatever the rim diameter.

Remember this study is about rolling resistance - not the kinetic energy (momentum) and angular velocity of a larger mass wheel - or the incident angle of a larger diameter wheel.

For some context. The factory XCO teams running non tubulars on 29 wheels - Specialised and some fisher bikes - use skinny (29x1.95) where volume is a small 4232cm^3 at a higher pressure - in the 30's and sometimes 40's... though spotted spotted a Specialised press release saying they ran 24.5psi at Mont St Anne. (Don't know if they are serious about the 1/2psi thing - most teams go up and down in 2 or 3psi increments). They do this as well as run super light wheel sets to get the mass down to near their 26in rivals.


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## bholwell (Oct 17, 2007)

Electric Panda said:


> Some of you guys may want to catch up on the science of what is a fast tyre for off road. Wide high volume and low pressure has less rolling resistance ie faster... than light but narrow low volume and high pressure.
> 
> An interesting link came up over in the 29er forum in a ye olde 26v29 debate. Science is somewhat dismissed over there sometimes but this is worth looking at in an XC race forum.
> A reasonable study was done by Peter Nilges on tyre volume and pressure and the effect they have on rolling resistance. It is a little old but still relevant and the link is here http://www.mtbonline.co.za/downloads/Rolling_Resistance_Eng_illustrated.pdf
> ...


29er tires do not give a larger contact patch area than equivalent 26" tires. The contact patch is only related to the inflation pressure and the load. Similarly, a wide 26" tire does not yield a larger contact patch than a narrow 26" tire when inflated to the same pressure, given the same load. Only when the pressure is reduced or the load is increased does the area increase. Now the shape of the contact patch is different in both instances, but that is a different discussion.

Also, not all off-road trails are rough, bumpy, rocky, or rooty. Some are smooth, buff hardpack. Therefore not all trails are best suited to high volume XC race tires.

And I've found that I cannot run a 29er tire at any lower pressure than an identical 26" tire before lateral flex in the corners becomes an issue. The lower rolling resistance of a 29er tire is mostly due to the shallower angle of incidence when rolling over an obstacle- flexing the sidewall of a XC race tire imparts very little resistance.


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## Nooge (Mar 9, 2009)

bholwell said:


> 29er tires do not give a larger contact patch area than equivalent 26" tires. The contact patch is only related to the inflation pressure and the load. Similarly, a wide 26" tire does not yield a larger contact patch than a narrow 26" tire when inflated to the same pressure, given the same load. Only when the pressure is reduced or the load is increased does the area increase. Now the shape of the contact patch is different in both instances, but that is a different discussion.
> 
> Also, not all off-road trails are rough, bumpy, rocky, or rooty. Some are smooth, buff hardpack. Therefore not all trails are best suited to high volume XC race tires.
> 
> And I've found that I cannot run a 29er tire at any lower pressure than an identical 26" tire before lateral flex in the corners becomes an issue. The lower rolling resistance of a 29er tire is mostly due to the shallower angle of incidence when rolling over an obstacle- flexing the sidewall of a XC race tire imparts very little resistance.


True the area does not change, but the change in shape has an impact. The skinny tire's long contact patch means more sidewall deflection than the fat tire's stout contact patch. On hard pack in a straight line the fatter tire will roll better. However on a MTB there are many other factors like cornering, bumps, traction, etc.

The most important factor in my opinion is confidence. If you feel like you can corner better and brake less, then you probably will and that will make a greater difference than a slight difference in tire characteristics.


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## bholwell (Oct 17, 2007)

Nooge said:


> True the area does not change, but the change in shape has an impact. The skinny tire's long contact patch means more sidewall deflection than the fat tire's stout contact patch. On hard pack in a straight line the fatter tire will roll better. However on a MTB there are many other factors like cornering, bumps, traction, etc. .


Yes, the shape of the contact patch does matter. You have it backwards, however. A longer skinny contact patch will flex the sidewall and the shoulder area less. And on completely smooth hardpack, a fatter tire will not roll better. A skinnier tire with less rubber in the tread will.



Nooge said:


> The most important factor in my opinion is confidence. If you feel like you can corner better and brake less, then you probably will and that will make a greater difference than a slight difference in tire characteristics.


I absolutely agree with this statement. One always needs to have complete confidence in one's tires.


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## Cheers! (Jun 26, 2006)

There is also the Schwalbe Furious Freds to consider.


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## davetrials (Feb 27, 2012)

Electric Panda said:


> Some of you guys may want to catch up on the science of what is a fast tyre for off road. *Wide high volume and low pressure has less rolling resistance ie faster... than light but narrow low volume and high pressure. *


Wide, high volume and low pressure is surely slower..


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## mariosimas (Nov 30, 2009)

OLx6 said:


> Someone has to suggest it.
> 
> I love my Conti Race King 2.2 Supersonics.
> 
> ...


i´m also using the Conti Race King SS but in size 2.0 in the rear weell.

Mine weight 430g.

the SS version have the ateral walls very thin. I´m thinking for the dry season use the

Conti Twister Supersonic 1.9 for the rear weel:










370g. Any feedback for this tire ?


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## John Kuhl (Dec 10, 2007)

The Schwalbe Furious Freds are very fast and light. Not
the best traction though.

Best, John


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## Electric Panda (Jan 8, 2006)

bholwell said:


> 29er tires do not give a larger contact patch area than equivalent 26" tires. The contact patch is only related to the inflation pressure and the load. Similarly, a wide 26" tire does not yield a larger contact patch than a narrow 26" tire when inflated to the same pressure, given the same load. Only when the pressure is reduced or the load is increased does the area increase. Now the shape of the contact patch is different in both instances, but that is a different discussion.


 yes. pretty sure that was what was said. only when you increase volume _(oops ... which allows lower psi)_ does the tyre contact patch increase - which is therefore not an equivalent sized tryre



bholwell said:


> Also, not all off-road trails are rough, bumpy, rocky, or rooty. Some are smooth, buff hardpack. Therefore not all trails are best suited to high volume XC race tires.


The study only differentiated between tarmac, gravel and meadow... I guess if your trails are like tarmac then this might be the case.



bholwell said:


> And I've found that I cannot run a 29er tire at any lower pressure than an identical 26" tire before lateral flex in the corners becomes an issue. *The lower rolling resistance of a 29er tire is mostly due to the shallower angle of incidence when rolling over an obstacle*- flexing the sidewall of a XC race tire imparts very little resistance.


Not sure what you are saying there. According to this study the higher volume tyre should allow for lower pressures to be run - whether that higher volume is in a 2.4 x26 tyre (6055cm^3) at 21 psi or a slightly lower volume 29x2.25 tyre (5935cm^3) at, say 23psi. the higher volume tyre will have less sidewall flex than a lower volume tyre at the same psi.

incidence angle over obstacles is a contentious issue. No specific study has been done, or is likely to be done as obstacles make up a smaller percentage of a race track. Rolling resistance is more about the stuff you are riding on between the logs etc. And that is where sidewal flex is one of the issues that increases rolling resistance and where a larger volume tyre is more effecient according to this study. The dia of the wheel does not dictate whether you can run a high volume tyre or not... ergo better rolling resistance is not the sole domain of a 29 wheel... yes you can run a 29x2.4tyre - and many SS do - but the increase in mass puts mosts racers of doing this. Certainly in XCO the favourite amongst factory teams that run 29's is a skinny (1.9) tyre at high pressure.

I would be very interested if you have data that contradicts this study as that is what science is all about.


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## Electric Panda (Jan 8, 2006)

davetrials said:


> Wide, high volume and low pressure is surely slower..


depends whether you believe in science or people in internet forums 

have a read of Nilges study - there is a significant advantage


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## jtmartino (Jul 31, 2008)

davetrials said:


> Wide, high volume and low pressure is surely slower..


Absolutely wrong. Good try though.


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## Guest (Mar 21, 2012)

Electric Panda said:


> depends whether you believe in science or people in internet forums


It's ironic that you advocate science by linking to that study. :lol: That master's thesis was highly flawed and is not science if for no other reason that is impossible to reproduce. It also fails to support the claim that wider is faster except in grass. While the ideas have merit, that paper doesn't provide a convincing argument. It helps Schwalbe sell tires, though.

Whether wider and softer is faster depends on conditions as bhowell has already pointed out. Lower pressures mean greater continuous rolling losses but also potentially better conformance to terrain. If you have smooth terrain, the result will be slower. Bhowell is right.

Gross generalizations rarely lead to ideal results.


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## Electric Panda (Jan 8, 2006)

craigsj said:


> It's ironic that you advocate science by linking to that study. :lol: That master's thesis was highly flawed and is not science if for no other reason that is impossible to reproduce. It also fails to support the claim that wider is faster except in grass. While the ideas have merit, that paper doesn't provide a convincing argument. It helps Schwalbe sell tires, though.
> 
> Whether wider and softer is faster depends on conditions as bhowell has already pointed out. Lower pressures mean greater continuous rolling losses but also potentially better conformance to terrain. If you have smooth terrain, the result will be slower. Bhowell is right.
> 
> Gross generalizations rarely lead to ideal results.


Hmmm&#8230; lets see what we agree on&#8230;

all studies can use more data sets (at least in my 25yrs experience) - this one has a small data set and there is no comment on any controls used (though there could have been - this is just a reprint for a magazine)&#8230; 
'impossible to reproduce'? He laid out his methodology fairly clearly within the paragraphs that were reprinted&#8230; On my brief perusal I would have thought it was fairly straightforward to reproduce&#8230; and this is of course important&#8230; science is all about being able to reproduce results and findings&#8230; Perhaps you could elaborate on that one - it may be that I have missed something in your meaning&#8230;

&#8230; in the context of opinions on an internet forum it is 'science' enough IMHO&#8230; what controls did you have in mind before you would call a study 'science'?

the study and most studies/experiments can have holes picked in them and the less controls with the less information the more questions can be asked&#8230;

this study provides some indication that wider and lower pressures is faster on gravel and grass - more distinct on grass&#8230;

whether the study provides a 'convincing argument' is subjective to the reader&#8230; 
yes Schwalbe tyres benefited, seeing as it was pretty much an unpaid plug for their different types&#8230; don't know that it is particularly relevant &#8230; other than the semi slick had a different carcass type

Yes wider softer is faster depending on conditions - this was one of the principal arguments in Nilge's study&#8230; to the limit the data set provided IMHO it does a good job &#8230;

If you have smooth tarmac (or hardpak that is as smooth as tarmac) the results showed more volume at low pressures is not the answer. No-one disputes this.

Gross generalizations do indeed rarely lead to ideal outcomes in the real world&#8230;

Now lets look at the flip side&#8230; there is no current study- small or otherwise - I know of (you or Bhowell may have) that indicates that skinny, high pressure tyres provide better (ie less) rolling resistance on gravel or grass


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## bholwell (Oct 17, 2007)

Electric Panda said:


> yes. pretty sure that was what was said. only when you increase volume _(oops ... which allows lower psi)_ does the tyre contact patch increase - which is therefore not an equivalent sized tryre.


Since the contact patch area is only dependant on the inflation pressure and the load on the tire, yes, running lower pressure will yield a larger contact patch. However it is not always possible to run lower pressure with a higher volume tire. A larger tire carcass results in a "taller" tire, which can cause the tire to "roll" laterally on the rim (particulaly narrow rims) when cornering.



Electric Panda said:


> The study only differentiated between tarmac, gravel and meadow... I guess if your trails are like tarmac then this might be the case.


That is one of the reasons the study can be misleading. The hypothetical trail in question does not need to be as smooth as tarmac to be one where a smaller tire is ideal. The course at Sea Otter comes to mind.



Electric Panda said:


> Not sure what you are saying there. According to this study the higher volume tyre should allow for lower pressures to be run - whether that higher volume is in a 2.4 x26 tyre (6055cm^3) at 21 psi or a slightly lower volume 29x2.25 tyre (5935cm^3) at, say 23psi. the higher volume tyre will have less sidewall flex than a lower volume tyre at the same psi.


But aren't you advocating running the higher volume tire at lower pressure?



Electric Panda said:


> incidence angle over obstacles is a contentious issue. No specific study has been done, or is likely to be done as obstacles make up a smaller percentage of a race track. Rolling resistance is more about the stuff you are riding on between the logs etc. And that is where sidewal flex is one of the issues that increases rolling resistance and where a larger volume tyre is more effecient according to this study. The dia of the wheel does not dictate whether you can run a high volume tyre or not... ergo better rolling resistance is not the sole domain of a 29 wheel... yes you can run a 29x2.4tyre - and many SS do - but the increase in mass puts mosts racers of doing this. Certainly in XCO the favourite amongst factory teams that run 29's is a skinny (1.9) tyre at high pressure.
> 
> I would be very interested if you have data that contradicts this study as that is what science is all about.


Again, the rolling resistance imparted to the system from sidewall flex is very small compared to the resistance caused by the hysteresis of the rubber compound of the tread, the tread pattern design, the flexing of the tire casing and breaker, and the losses caused by vertical motion from irregularities in the trail.

When you say that "rolling resistance is more about the stuff you are rinding in between the logs", well, I contend that it's actually about the trail conditions on every part of the trail. Many of the trails on the east coast are continuously littered with roots and rocks- barely a smooth spot anywhere. These trails are more suited to a 29er tire due to the lower incidence angle.

Anyhow, the moral of the story is that different courses suit different tires. Do not blindly believe everything you read online. The point I was simply trying to make was that just because you might be racing off road, a wide, fat tire isn't always the best (i.e. fastest) choice.

P.S. I'd love to share my data with you, but it is confidential to my company.


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## Guest (Mar 21, 2012)

Electric Panda said:


> &#8230; science is all about being able to reproduce results and findings&#8230; Perhaps you could elaborate on that one - it may be that I have missed something in your meaning&#8230;


The author described his methodology to some extent but hardly to a "scientific" extent. Furthermore, rolling resistance testers have found that even textured rollers introduce so much uncertainty that testing becomes irreproducible. Testing a bike over barely described, and non-preserved, surfaces cannot be. Then there's all the methodology he didn't describe, including for example how he separated the effects of tread and width and resolved differences in width among the tires, or even how many samples of each tire and how many runs of each test he ran. There's no discussion of any of that, nor was the author likely even aware of the importance. The author started with a presumption and set out to produce some results that supported it. That's exactly the opposite of science; it's not testing a hypothesis, it's comforting a prejudice.



Electric Panda said:


> &#8230; in the context of opinions on an internet forum it is 'science' enough IMHO&#8230; what controls did you have in mind before you would call a study 'science'?


Haha, that's nothing to hang your hat on. The weakness other people call "science" doesn't raise non-science to the level of science.

I have no "controls" in mind to call a study "science"; it is not up to me to decide. Science is "scientific", it is not dependent on the individuals making the argument. I have already pointed out some failings already.



Electric Panda said:


> this study provides some indication that wider and lower pressures is faster on gravel and grass - more distinct on grass&#8230;


No it didn't, and that's where your willingness to call it "science" is a problem. There's no discussion of relevant results in the study. There's no way the data presented on tire width supports the conclusion on road and gravel. It isn't science, it's handwaving and wishful thinking.



Electric Panda said:


> Yes wider softer is faster depending on conditions - this was one of the principal arguments in Nilge's study&#8230; to the limit the data set provided IMHO it does a good job &#8230;


It is also NOT faster depending on conditions, and that is contrary to one of the principal arguments of the study. You can't pick and choose the data and call it science.



Electric Panda said:


> If you have smooth tarmac (or hardpak that is as smooth as tarmac) the results showed more volume at low pressures is not the answer. No-one disputes this.


Thank you for admitting your error.



Electric Panda said:


> Now lets look at the flip side&#8230; there is no current study- small or otherwise - I know of (you or Bhowell may have) that indicates that skinny, high pressure tyres provide better (ie less) rolling resistance on gravel or grass


Yes, but that is a different matter. It is also true that there are more options than wide or skinny, soft or hard. The right answer is, as it has always been, that you need enough tire for the conditions. More is slower. That's a critical point in a discussion of light and fast XC racing tires. The Maxxlite was mentioned and criticised for being inadequate. That failure is due to the "wider is always better" myopia.

Looking at the same issue from an even more obviously absurd viewpoint, there is a poster here who has claimed to be able to win road races because of his secret weapon, Big Apples on a 29er instead of skinny road race tires. Wider and lower pressure is always faster, right? In the Fatbike forums, there are those that claim that Fatties have lower rolling resistance because they are wider and lower pressure as well. See the problem with the logic now?


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## realconspiracy (Jan 22, 2011)

More experiments needed..


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## RaveOn (Dec 21, 2003)

realconspiracy said:


> More experiments needed..


Experiments in actual riding and less bla bla bla... :cornut:


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## realconspiracy (Jan 22, 2011)

RaveOn said:


> Experiments in actual riding and less bla bla bla... :cornut:


:thumbsup: Thread closed for now


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## Electric Panda (Jan 8, 2006)

bholwell said:


> Do not blindly believe everything you read online.


I am perplexed by this comment&#8230; 
this study was done by a grad student to write his thesis&#8230; that is then reviewed, generally, by a board of examiners... 
In my country this would typically be a professor, an associate professor or two, as well as a lecturer or two perhaps with specialized knowledge - I am of the opinion it is similar in Germany. 
Obviously these learned people thought Nilges thesis passed the Fit for Purpose examination, Methodology used, controls used, analysis of the raw data and no particular errors were found in the conclusions drawn. Otherwise he would have flunked. 
In my view, and I believe most others, this makes it a worthy text to consider. 
Does this mean it is fact? Of course not. It is a bunch of data that points to the conclusions drawn. But _'blindly believe everything you read online '_ I believe is not an appropriate response here&#8230;



bholwell said:


> Anyhow, the moral of the story is that different courses suit different tires.


No one has offered a view counter to this.



bholwell said:


> The point I was simply trying to make was that just because you might be racing off road, a wide, fat tire isn't always the best (i.e. fastest) choice.


OK here, in my view, you are splitting hairs. Nilge talks about changing the psi for more tarmac or if the race is more tarmac orientated&#8230;. Tarmac is flat hard stuff with small bumps&#8230; No one has disagreed on the fundamentals here. Lets not create an argument where there is essentially not one.

Same with sidewall flex&#8230; can't even remember if he uses that exact term&#8230; but it is pretty close in the context to tire casing and bead, vertical motion&#8230; ? isn't that what causes the tire to flex&#8230;? rubber compound, tread pattern &#8230; sure he mentions it with the different tyres&#8230; l would suggest we are in the same boat with different paddles&#8230;



bholwell said:


> When you say that "rolling resistance is more about the stuff you are rinding in between the logs", well, I contend that it's actually about the trail conditions on every part of the trail. Many of the trails on the east coast are continuously littered with roots and rocks- barely a smooth spot anywhere. These trails are more suited to a 29er tire due to the lower incidence angle.


Riding between where you are getting air by popping a log&#8230; is that better? Come on &#8230; I think we all know what the tire hits - call it what you want&#8230;

You offered an opinion that a different sized wheel is faster because of incident angle.

If you have data - any data at all - that even sniffs of fit for purpose... has a mention of methodology... and a passing interest in control... then the good folks over on the 29er forum would love to hear about it - cause right now the only two studies I have found that even come close to being 'scientific' say the opposite.



bholwell said:


> P.S. I'd love to share my data with you, but it is confidential to my company.


I can understand your company not wishing to share contractual information or manufacturing process or compound materials&#8230; but broad brush stuff like this?!


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## mucky (Dec 17, 2010)

craigsj said:


> Looking at the same issue from an even more obviously absurd viewpoint, there is a poster here who has claimed to be able to win road races because of his secret weapon, Big Apples on a 29er instead of skinny road race tires. Wider and lower pressure is always faster, right? In the Fatbike forums, there are those that claim that Fatties have lower rolling resistance because they are wider and lower pressure as well. See the problem with the logic now?


The guys in the Tour de France must run skinny tires and high pressure because they want to go slower. What are they thinking:madman:

What is the lightest XC tire?


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## Guest (Mar 22, 2012)

Electric Panda said:


> You offered an opinion that a different sized wheel is faster because of incident angle.
> 
> If you have data - any data at all - that even sniffs of fit for purpose... has a mention of methodology... and a passing interest in control... then the good folks over on the 29er forum would love to hear about it - cause right now the only two studies I have found that even come close to being 'scientific' say the opposite.


It's curious that. as a man of "science", you don't realize the simple fact that wheel radius is a direct contributor to rolling resistance. We don't need studies to prove that, you can read all about it over at Wikipedia.

But at least you are calling this a study now rather than science.


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## Electric Panda (Jan 8, 2006)

To Craigsj, your last post I am not going to bother quoting.

This study was done by a grad student to write his thesis… that is then reviewed, generally, by a board of examiners... 
In my country this would typically be a professor, an associate professor or two, as well as a lecturer or two perhaps with specialized knowledge – I am of the opinion it is similar in . 
These learned people thought Nilges thesis passed the Fit for Purpose examination, Methodology used, controls used, analysis of the raw data and no particular errors were found in the conclusions drawn. Otherwise he would have flunked. 

This is what science is all about - Peer reviewed data and its conclusions. 

If in your opinion it is not – then of course you are welcome to your position. I am confident that Nilge and the professor/s and whoever else who sat on his review panel would hold your opinion in an order of regard that is relevant. 

To be fair to you, this is only a magazine article… if you were to read Nilges thesis it may be that you would agree with the board of examiners that it is indeed ‘science’. I am happy with a re-edit of a thesis that has passed this level of scrutiny. 

A 2.4 Racing Ralph is faster than the other tyres tested and 21 psi is the most efficient pressure of all the pressures tested on gravel to meadow. 21 psi is not the most efficient on tarmac. By inference there is an effeciency crossover point between gravel and tarmac. The thesis has been peer reviewed and has now become scientific fact within the constraints of the methodology and controls until another study – similarly reviewed - comes along to refute it.

Your opinions have not.

You made a comments like, “howelbj is right’ the inference being I, or Nilge were wrong. Also ‘Thank you for admitting your error’. The inference being I was wrong and was admitting it. 

A puerile argumentative style that someone of your obvious intelligence shouldn’t have to stoop to.

Your last paragraph about other peoples opinions - and your opinions on them - have nothing what ever to do with this properly reviewed thesis and its conclusions.


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## Guest (Mar 22, 2012)

Electric Panda said:


> This study was done by a grad student to write his thesis&#8230; that is then reviewed, generally, by a board of examiners... These learned people thought Nilges thesis passed the Fit for Purpose examination, Methodology used, controls used, analysis of the raw data and no particular errors were found in the conclusions drawn. Otherwise he would have flunked.
> 
> This is what science is all about - Peer reviewed data and its conclusions.


And that's where you are wrong. Peer review is done in public and all the infornation required is made public. All we have here is your assumption that his professors did this work. Frankly, that is unlikely. You appear to have no experience with graduate school.



Electric Panda said:


> If in your opinion it is not - then of course you are welcome to your position. I am confident that Nilge and the professor/s and whoever else who sat on his review panel would hold your opinion in an order of regard that is relevant.


Condescension doesn't suit you. Problems with this paper scientifically are glaring and I've already mentioned some of them. Go ahead, though, make your appeal to imaginary authority, it's all you have.



Electric Panda said:


> To be fair to you, this is only a magazine article&#8230; if you were to read Nilges thesis it may be that you would agree with the board of examiners that it is indeed 'science'. I am happy with a re-edit of a thesis that has passed this level of scrutiny.


Of course, despite not having the original thesis nor any evidence of the level of scrutiny your speak of. More of your appeal to imaginary authority.



Electric Panda said:


> A 2.4 Racing Ralph is faster than the other tyres tested and 21 psi is the most efficient pressure of all the pressures tested on gravel to meadow. 21 psi is not the most efficient on tarmac. By inference there is an effeciency crossover point between gravel and tarmac. The thesis has been peer reviewed...


You are quite the B.S.er, aren't you? The thesis hasn't been peer reviewed. The author was a student, the examiners not his peers, and the standards applied not scientific rigor. The professors cared only if it met their standard for a master's degree and it is questionable that any of them had functioning expertise in the subject.

Who knows what the actual data is. All that was presented (p.8) was a comparison of two tires of different widths, threads, and tire pressures. That's the exact opposite of science.



Electric Panda said:


> ...and has now become scientific fact within the constraints of the methodology and controls until another study - similarly reviewed - comes along to refute it.


You are now arguing like a fanboy. Science involves critical thinking, something it's becoming clear you are incapable of.



Electric Panda said:


> You made a comments like, "howelbj is right' the inference being I, or Nilge were wrong. Also 'Thank you for admitting your error'. The inference being I was wrong and was admitting it.


And you were. When confronted with evidence contrary to your claims, from your own source no less, you reneged.

Let's keep in mind the conclusions of the paper, found in bold on page 8, that "*FIRMLY inflated narrow tyres are history. 'Fat' and less air speed things up!*". Except, of course, when they don't, in which case "No-one (sic) disputes this" as you say. Way to ignore the elephant in the room.



Electric Panda said:


> A puerile argumentative style that someone of your obvious intelligence shouldn't have to stoop to.


Look who's talking.



Electric Panda said:


> Your last paragraph about other peoples opinions - and your opinions on them - have nothing what ever to do with this properly reviewed thesis and its conclusions.


Once again with the outright lies. What does it say about someone who resorts to intellectual dishonesty in order to win an argument?

This paper is simple anecdotal evidence from a student that has become marketing material for a company who most likely sponsored it.


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## Electric Panda (Jan 8, 2006)

You are being as arseh0le mate.

The guy was a post grad student doing a post grad thesis.
Like all such work it passed a board of examiners - which in my country and, because Germany also rates very highly on the OECD scholastic scores, I assume in Germany also - is made up of people who have studied and published enough to be professors, associates etc in the field the thesis covered.
The thesis would then be made available to anyone, including the public, who is interested by being listed in the University Library or equivalent.

It may be that in your country this is not the case &#8230; and that _' The professors cared only if it met their standard for a master's degree and it is questionable that any of them had functioning expertise in the subject'_

Not happy that your unsubstantiated opinions are not shared over properly constructed and reviewed data - you go on to insults. Clever.

When I first read the calcs you presented to back up a discussion on another thread I wondered why, given the amount of posts you have and the quality of that data in that thread, you would not have more 'reps'. 
I now know why that is.


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## Sideknob (Jul 14, 2005)

In answer to the original question - depends on the nature of the course.  Not all XC race courses are smooth, baked clay. Some courses will have sharp rocks, pea gravel, roots, mud etc etc.

A tyre like the Maxxis 285 would haul on the open fire road courses around here (and one day I will try them) - but get cut to ribbons on the rocky, untamed singletrack.


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## jtmartino (Jul 31, 2008)

I'd like to add that weight doesn't seem to be as much of a factor as "engine." As evidence, I'll point out Nino Schurter's recent World Cup win on relatively porky Dugast tubulars (compared to the Maxxlite). 


So rather than see the arguing back and forth about the credibility of the Schwalbe study, how would you guys design the experiment? I assume it would be pretty challenging given the argument that one tire is "faster" than the other.


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## Guest (Mar 22, 2012)

Electric Panda said:


> You are being as arseh0le mate.


Look who's talking.



Electric Panda said:


> The guy was a post grad student doing a post grad thesis.
> Like all such work it passed a board of examiners - which in my country and, because Germany also rates very highly on the OECD scholastic scores, I assume in Germany also - is made up of people who have studied and published enough to be professors, associates etc in the field the thesis covered.


Ridiculous. They are *students*. :lol: Ever been to school?



Electric Panda said:


> The thesis would then be made available to anyone, including the public, who is interested by being listed in the University Library or equivalent.


Do you have it?



Electric Panda said:


> Not happy that your unsubstantiated opinions are not shared over properly constructed and reviewed data - you go on to insults. Clever.


I love how you consider science and peer review to be opinions and how you believe that continually restating your lie that the article was peer reviewed somehow makes it so. This is what "science" is to you, pretense in a forum.



Electric Panda said:


> When I first read the calcs you presented to back up a discussion on another thread I wondered why, given the amount of posts you have and the quality of that data in that thread, you would not have more 'reps'.
> I now know why that is.


So you are a hypocrite as well. Given your apparent respect for the rep system, it's no surprise you are so easily fooled.

For all your pretense about how much better your country's educational system is, how the students enter as published experts in their fields, how their professors are also experts who peer review their work, and how a master's thesis constitutes scientific fact through it's very existence, you have no idea what's actually in the thesis or how it was reviewed or if anyone has come close to duplicating the results. What you do have is the ability to call me an "arseh0le" with unsubstantiated opinions and a popularity problem. You are exactly like those people you disrepected "over in the 29er forum", lots of pretense of knowledge but ultimately all you are is a blowhard who sees bluffing and doubling down as winning strategies. Too bad you don't put as much effort into learning as you do into pretending to know what you are talking about.


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## Guest (Mar 22, 2012)

jtmartino said:


> So rather than see the arguing back and forth about the credibility of the Schwalbe study, how would you guys design the experiment?


You would suggest "designing an experiment" with someone who believes the question is answered already? 

First off, you don't have to design an experiment to know what's wrong with another. Second, rolling resistance tests are quite challenging even on smooth surfaces with with smooth treads. Go over to bike tech review and learn how involved it is and how dedicated they are at sustaining reproducible results. The efforts they make to produce even modest results make the Schwalbe study look comical and amateurish, which it is. Lastly, you make the assumption that an experiment could be designed that would enable the conclusions made in the study. I don't believe that's the case, I believe the scope is too great, the subject too complex, and the conclusions too simplistic.

I spent a good deal of my professional time instrumenting performance and a tremendous amount of that effort involves making sure you can believe your results. First and foremost is repeatability and reproducibility. Those things are quite often NOT gotten right, and when people find someone who has, they cling on. There is absolutely no reason to believe the author of the study understands any of that, nor would he considering he was still a student at the time.


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## fastback67 (Apr 6, 2010)

mucky said:


> The guys in the Tour de France must run skinny tires and high pressure because they want to go slower. What are they thinking:madman:
> 
> What is the lightest XC tire?


beside maxxis the geax aka pluma withh 295g: products « Geax.com


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## trekfueler (Mar 16, 2009)

Rolling Resistance | Schwalbe North America


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## Spinning Lizard (Nov 27, 2009)

Are we talking about tires or Global Warming?


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## magas (Aug 22, 2008)

Maxxis larsen TT, the one I like to ride in, almost, all conditions.

recently I ride a bike which was shot in Vredestein Black Panther 2.0 and they felt perfect in the conditions I tested them (dry forrest roads, small forrest paths with rocks and roots), therefore I bought a set of them for my current build. looking forward testing them in all conditions throughout this season. weight is arround 540 gr each. Dont know if Vredesteins are available in the US ?


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## badger2071 (Mar 18, 2007)

Reading the both of your rantings back and forth was the most painful 5 minutes of my life that I will never get back.

Getting back to topic I am a big fan of RaRa as well. It does wear rather fast though.


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## suprteck (Sep 27, 2009)

Ritchey Z-max evolutions 2.1 455g. I run these tubeless with stans and they have great grip in all conditions and super light.


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## panzer07 (Jun 18, 2008)

Specialized S-WORKS 29r Fastrack front 2.0 @ 520 grams and S-WORKS Renagade rear 1.95 @ 470 grams . These tires rip and are durable for XC racing - super fast! :thumbsup:


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## locknload223 (Mar 23, 2012)

suprteck said:


> Ritchey Z-max evolutions 2.1 455g. I run these tubeless with stans and they have great grip in all conditions and super light.


How do you like this as a rear tire? I've always liked the classic Z-Max for the front but usually ran a different rear.


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## suprteck (Sep 27, 2009)

locknload223 said:


> How do you like this as a rear tire? I've always liked the classic Z-Max for the front but usually ran a different rear.


No problems with it in the rear. Grips good and predictable.


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## Sideknob (Jul 14, 2005)

Maxxis Monorail Exception.

Maybe paired with a Crossmark up front if conditions are a bit loose.

I also like the Tioga Red Phoenix.


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## loggerhead (Mar 8, 2009)

Maxxlite really are a show tire as mentioned. Tore knobs off of sidewalls from one ride. 'Race only' is what is stated. Anything Supersonic and you will have the same results.:nono:


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## CrozCountry (Mar 18, 2011)

All of you that want a more grippy race king, check out the X-King.
I use it as rear. It can spin out on steep bare rock surface climbs, especially on wet, but not anywhere else.


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