# Going mullet - geometry and travel change question



## crembz (Feb 25, 2019)

I'm in the process of converting a scout 275 into a mullet or whatever they're called. Main reason is I love the way my 29er rolls but love the way this bike 'feels'. I'm hoping to get the best of both worlds with this setup. I'm looking to run 29x2.6 up front and 27.5x2.8 in the rear.

I understand that the larger front wheel is going to push the front end up slightly, increase my HTA and BB height. I'm happy with that as I don't think the changes are large enough to ruin the characteristics of the bike.

I need to change my fork however. 29x2.6 will not fit the stock 140mm RS Sektor I currently have. So I'm looking into what I should change it to:

RS Sektor 29" 140mm A2C 553 
RS Revelation 29" 140mm A2C 551
RS Yari 29" 150mm A2C 561

All those shocks have a 51mm offset.

A2C measurement on the stock sektor is 534 with a 46mm offset. 

As I understand, increasing the offset and a longer A2C both slow down the steering input. I'm a little concerned that the combined difference will make the bike a bit of a pig around corners. Am I thinking about this correctly?

Or does the larger offset (shorter trail) cancel out some of the increased A2C height?


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## LoneStar (Jun 17, 2004)

Might want to throw in slackening the seat tube angle as well as to some of the repercussions of going to a 29 front. If you are getting a new fork, you may want to reduce the travel a bit to keep the geometry in the same ballpark as what you have.


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## crembz (Feb 25, 2019)

Yeah I actually spoke to the resident mullet expert at a supplier. He pointed out that keeping the same travel together with the difference in wheel sizes will change the hta by up to 3°. Comparing what the ews guys are doing, they're fitting a 10mm shorter fork than the frame was specced with to offset the difference.

He also suggested running a slightly narrower front tyre (2.5) to rear (2.6) could help further keep geometry similar.

I've ended up going with a marzocchi Bomber fork which should get me Yari + like performance at 130mm travel. I've got all the bits I'll need order now so just need to wait until they all arrive.


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## kevin_sbay (Sep 26, 2018)

crembz said:


> I've got all the bits I'll need order now so just need to wait until they all arrive.


Cool. Excited to hear how your experience goes.
I have a set of 29ers coming and will experiment with them and my 27.5s on my Spesh Fuse, which can handle both sizes.


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## crembz (Feb 25, 2019)

Sweet it's going to take a couple of weeks to get everything. Fork I should have this week. Wheels next week. I'm lowering the bar rise and shortening the stem to try offset the potential 2° slacker hta and the expected slower steering & increased stack. Those I should have this week.


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## PuddleDuck (Feb 14, 2004)

I'm also interested to hear how it all comes together, and how it feels and rides. Keep it coming :thumbsup:


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## crembz (Feb 25, 2019)

No worries I might start a seperate build thread. One thing is converting isn't cheap! Wheels & fork cost half as much as the bike. I am however taking the liberty of upgrading while I'm at it 😁.

It would be a lot cheaper to start off with a 29er than a 650b. Problem with that is lowering the BB if it's already low. The other is if you're a short rider or just don't fit most 29ers like me.

Based on what's being done by the pros, starting from a 650b seems the way to go but more expensive overall. Eager to see how it actually feels.

Worst case, I hate it, revert back to stock spec and have enough spares to build up another bike sans frame.


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## PuddleDuck (Feb 14, 2004)

Sounds like you've got a good plan :thumbsup: It's good to have options...and one can never have too many bikes 

I'm pondering converting a 140mm 650b that's got a 150mm fork, but I don't want to slacken the too much. Even if I downsize to a 130mm 29 fork, I'll probably still be at least 1 degree slacker. 

I like your idea about running a plus sized rear tyre, but I don't want to slow the bike down too much...


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## S​​usspect (May 12, 2017)

Cool thread to see today, as I'm tinkering with a "mullet" right now too... in my case, just finding a way to use an extraneous 29+ front wheel/tire that has a 100mm thru axle. I ordered a boost converter and put the wheel on my 27.5+ hardtail (Norco Torrent). I have not had a chance to hit the trail yet but my neighborhood/side of the hill spin was fun. I will adjust the saddle a little before I go for an actual ride, I can feel the rear end is lower and my weight is back, but it climbed the hill fine.

Right now it has a 27.5x2.8 on the rear, but I ordered a 3.0 tire for cheap on eBay, so that should bring it up about 1/4". The bike has a 130mm fork, and was specced with 140mm, so that will also help restore some balance (I assume).

I don't know if it's a long term solution for anything, but for $60 invested it should be a fun experiment... I'll be listening to what you other mad scientists find out too.


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## RS VR6 (Mar 29, 2007)

Sounds interesting. I'm thinking about swapping the fork from my Following to the Spitfire. Following (120mm rear) is a 130mm fork and the the Spitfire (140mm rear) is 150mm.


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## Verbl Kint (Feb 14, 2013)

Went mullet too, but with a Kona Process:

https://forums.mtbr.com/kona/kona-process-153-97-5-29-front-27-5-rear-build-1100874.html


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## crembz (Feb 25, 2019)

Verbl Kint said:


> Went mullet too, but with a Kona Process:
> 
> https://forums.mtbr.com/kona/kona-process-153-97-5-29-front-27-5-rear-build-1100874.html


Nice one. How did it play or with the rear suspension? In my mind the only way to tweak the hta on a hardtail is rear/front tyre difference in radius and a2c. Did you tweak the sag on the rear shock to balance things out?


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## LoneStar (Jun 17, 2004)

I actually did the mullet thing with my last bike, a 2014 Pivot Mach 5.7c. While it was a 26" frame, Pivot had blessed the use of 27.5 on both ends. It required reducing the front and rear shock travel to make it 'OK'. I really didn't like it like that for a number of reasons (high bb, limited rear tire size were the main ones). Ended up putting a 26" rear wheel with a big volume tire and the bike just worked really well. Plus I got a little more rear travel back in the process. BB was still a bit taller than spec, but I could live with it. Moved on to another bike but that one found it's way to my son so I get to hop on it every now and then.


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## Crankout (Jun 16, 2010)




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## S​​usspect (May 12, 2017)

That's a nice selfie Crankout, but this thread is about bikes!

We may need an official "post up your mullet (bike)" thread. Unless I missed it, I can't find one... though there is one a few years old that was focused on hairstyles 🤔.

If someone gets one started, I'll post up once I get a picture of mine (and after going for a few test rides).


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## scottzg (Sep 27, 2006)

crembz said:


> I've ended up going with a marzocchi Bomber fork which should get me Yari + like performance at 130mm travel. I've got all the bits I'll need order now so just need to wait until they all arrive.


I had a large scout mocked up, so i threw your new combination in to the model.







It's shown with 2.25 tires and some of the build kit parts might not be right.


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## S​​usspect (May 12, 2017)

scottzg said:


> I had a large scout mocked up, so i threw your new combination in to the model.
> View attachment 1260185
> 
> It's shown with 2.25 tires and some of the build kit parts might not be right.


Huh... Looking at this I'm surprised to see changes to the reach and ETT (one shorter, one longer). I had not considered that. But it makes sense.

And longer wheelbase? HTA/STA was as far as I'd gone in my thoughts.


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## crembz (Feb 25, 2019)

Awesome mock up. What did you use to pull it together?

Makes complete sense. Stack rises so the ett intersects a new point on the st slightly father up, reach increases slightly.

13mm higher bb should actually work ok, the 275 has a pretty low BB to start with.

Wheelbase makes perfect sense too (hta) guessing the change in fork offset 46 to 51 helps mitigate that a little.

I expected a bigger impact to the hta tbh. 63° is where I thought it would end up.


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## scottzg (Sep 27, 2006)

crembz said:


> Awesome mock up. What did you use to pull it together?
> 
> Makes complete sense. Stack rises so the ett intersects a new point on the st slightly father up, reach increases slightly.
> 
> ...


bikeCAD. I build frames occasionally, and like to mock up hardtails i find interesting.

FWIW, I see your proposed build as problematic. I would want a 110mm fork with a 29" wheel on a scout, tops. What you propose is too far 'off the back' for my taste, by a large margin. The geo change will be much more influential than the wheel size. But try it for yourself.

I forgot to change the fork offset in the image above. Fixed.


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## crembz (Feb 25, 2019)

Interesting, that's more like what I was expecting. Being a small frame I'm not sure how things would change. 

A 110mm might be difficult to stomach for the type of riding I'm doing. Even 130 I was thinking might be a little short ☹


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## scottzg (Sep 27, 2006)

crembz said:


> Interesting, that's more like what I was expecting. Being a small frame I'm not sure how things would change.
> 
> A 110mm might be difficult to stomach for the type of riding I'm doing. Even 130 I was thinking might be a little short ☹


Small-









I don't 100% understand small frames; i'm very tall and the compromises are different. (and i'm not spending tons of time on this, i'm at work.) Still looks like a mess to my semi-trained eye. I'd like to hear your experiences once you've gotten familiar with it.


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## crembz (Feb 25, 2019)

scottzg said:


> Small-
> 
> View attachment 1260269
> 
> ...


Thanks for doing that, much appreciated. 63 degree hta is pretty aggro, more concerned about the sta tbh. Maybe tilting the saddle a little will help. It'll at the very least prove an interesting experiment 

Worst case, I order a 29" rear wheel and some long travel 29er frame and have a 4th bike (the wife is going to kill me).

ps, that vertical water bottle looks like it'l be a problem :winker:


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## scottzg (Sep 27, 2006)

crembz said:


> Thanks for doing that, much appreciated. 63 degree hta is pretty aggro, more concerned about the sta tbh. Maybe tilting the saddle a little will help. It'll at the very least prove an interesting experiment
> 
> Worst case, I order a 29" rear wheel and some long travel 29er frame and have a 4th bike (the wife is going to kill me).
> 
> ps, that vertical water bottle looks like it'l be a problem :winker:


I never bothered to change the dropouts or water bottle positions from the frame model i started with. 

Ask me to do a really excellent model and give me a day or two and i'll do it when i'm bored. It's like playing Sudoku. It's relaxing. For me, adding an inch of 'lower headset cup to ground' means the frame geo is botched, which is the case in your modification. I'm uninformed and pessimistic. I don't necessarily see any problems with 63* head angle in general, but yeah combined with that seat angle it's a problem. That's the trick- to look at the geo as a sum of its parts, not a bunch of numbers that should fall in a range.

IMO stock bb height is the low side of great, and you're moving it up past where i feel it's useful.


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## crembz (Feb 25, 2019)

Question, where did you find the A2C for the 29" fork in your model? From what I can tell a Fox 36 130mm A2C is 537. I see you've used 548. Wondering if I'm missing something.


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## crembz (Feb 25, 2019)

This isn't the first time I've done something funky with a bike.

My previous experiment ... the cyclo-mongrel. CX frame + Wheels, Flat bar, 1x XT drivetrain, Deore brakes, flat pedals & dropper post. I really enjoy this thing on the road and single track.


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## Crankout (Jun 16, 2010)

S usspect;14161363 said:


> That's a nice selfie Crankout, but this thread is about bikes!
> 
> We may need an official "post up your mullet (bike)" thread. Unless I missed it, I can't find one... though there is one a few years old that was focused on hairstyles ?.
> 
> If someone gets one started, I'll post up once I get a picture of mine (and after going for a few test rides).


There is a relatively recent thread in the OC about mullets and other 80's goings-on...


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## scottzg (Sep 27, 2006)

crembz said:


> Question, where did you find the A2C for the 29" fork in your model? From what I can tell a Fox 36 130mm A2C is 537. I see you've used 548. Wondering if I'm missing something.


I googled it. Mighta pulled up the wrong number. Give me fork specifications and i'll plop them in.


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## crembz (Feb 25, 2019)

I looked up the 36 specs here https://www.ridefox.com/fox17/help.php?m=bike&id=805. It only lists down to 140 mm but I took 10mm of the a2c of that and got to 537 which is 3mm taller than my current fork.


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## S​​usspect (May 12, 2017)

scottzg said:


> Ask me to do a really excellent model and give me a day or two and i'll do it when i'm bored. It's like playing Sudoku. It's relaxing.


I know you weren't talking to me, and that you are in fact a busy guy, but if you want to mock up a 2017 Norco Torrent HT I would certainly benefit from the information.

What I've got is a shorter 130mm fork (Fox Rhythm 34 replaced a 140mm DVO Diamond, best I can tell the A/C went from about 560 down to 540), and the rear wheel/tire will be 27.5x3.0 Specialized Ground Control (don't have it yet, but I have read it will measure 28.5" tall). Up front I have a 29x3.0 Bomboloni that is a little small and measures about 29 5/8" tall.

Just put me on ignore if you don't want to start mocking things up for all and sundry.


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## crembz (Feb 25, 2019)

Hey just checkout bikecad. I fired it up for the first time yesterday, picked a MTB quick design and punched in the relevant information for the frame, fork and wheels/tyres. Than I 'locked' the frame and changed the fork and wheels to the new specs to see what it does to the geometry.

The hardest part is finding the measurements online.

Now my first effort is probably nowhere near what scottzg has been able to do but it still gives a good idea of what is going to be changing and by how much. In my design HTA/STA change by 1.2 degrees. I know it's probably going to be more so i must have missed something. I expect closer to 2 degrees.


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## scottzg (Sep 27, 2006)

crembz said:


> Question, where did you find the A2C for the 29" fork in your model? From what I can tell a Fox 36 130mm A2C is 537. I see you've used 548. Wondering if I'm missing something.


You are correct. https://www.ridefox.com/fox17/help.php?m=bike&id=805 I used a 140 cuz i suck.









I'm happy to do you up, susspect. Pretty sure i have a torrent mocked up already.


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## crembz (Feb 25, 2019)

Thanks heaps mate, the angles don't look as extreme anymore.

My mock up came out at a 63.9° hta so I must've missed something.

Might be worth writing up a 'how to use bikecad' post, I reckon heaps of us would benefit greatly from your knowledge.


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## scottzg (Sep 27, 2006)

S usspect;14164813 said:


> I know you weren't talking to me, and that you are in fact a busy guy, but if you want to mock up a 2017 Norco Torrent HT I would certainly benefit from the information.
> 
> What I've got is a shorter 130mm fork (Fox Rhythm 34 replaced a 140mm DVO Diamond, best I can tell the A/C went from about 560 down to 540), and the rear wheel/tire will be 27.5x3.0 Specialized Ground Control (don't have it yet, but I have read it will measure 28.5" tall). Up front I have a 29x3.0 Bomboloni that is a little small and measures about 29 5/8" tall.
> 
> Just put me on ignore if you don't want to start mocking things up for all and sundry.


piece of cake. You should verify my numbers.

new fork- https://www.ridefox.com/fox17/help.php?m=bike&id=804









Torrent has a fairly slack seat angle and short chainstays. Looks like it could be pretty wheelie prone despite the modest change in geo.


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## S​​usspect (May 12, 2017)

scottzg said:


> piece of cake. You should verify my numbers.
> 
> new fork- https://www.ridefox.com/fox17/help.php?m=bike&id=804
> 
> ...


Awesome, thanks so much for doing this. It's way easier to understand the relationship of all the measurements with a diagram like this. You nailed the frame dimensions, I should have told you it's a Medium but you guessed right.

Can I ask about A/C? If I'm reading the diagram right, you have it at 543/546. The Fox link you shared confirms my current fork is 540 (it's a 29er) but I think the 140mm DVO was about 560. Anyways, maybe I'm just missing something.

And your right about the slack seat tube... even though I'm not the kind of rider that's going to pull an accidental wheelie! I actually took this bike on a test ride this evening, still using the 2.8 rear tire that's only 28" tall. I rode through a long, steep (up/down) techy loop with tons of rocks.... I was happy to find I didn't have any trouble tracking the front wheel on climbs, or any trouble keeping it down. It's kind of a Mack truck in the rocks, but it stays planted. I did find it was kind of heavy over rollers, didn't want to pop off the ground very easily. Some of these attributes may be just a part of 29+/switching to a heavier front wheel.

I appreciate your help with this, the diagram/discussion is definitely helping me understand this project better, cheers.


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## scottzg (Sep 27, 2006)

S usspect;14165215 said:


> Can I ask about A/C? If I'm reading the diagram right, you have it at 543/546. The Fox link you shared confirms my current fork is 540 (it's a 29er) but I think the 140mm DVO was about 560. Anyways, maybe I'm just missing something.


Im pretty sure that at the time i just plugged the rest of the numbers in, then set the A-C to whatever made the rest of it work. When everyone is using some sort of CAD to design frames it's easier to extrapolate from their numbers than it is to make accurate assumptions. Which has tons of implications........! In this case, it's interesting that the torrent was designed with the seat tube offset from the bb- it's meaningless in the real world, but it's obvious with CAD.

I'm glad it's helpful.  Personally, i think the stuff i can produce like this is only useful in a relative sense, so reader beware.


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## crembz (Feb 25, 2019)

Parts have started to arrive. Received the zocchi bomber today and the bonty XR5 29x2.6" front tyre. Stem has arrived also.

I'll keep my XR4 27.5x2.6" in the rear.

Wheels still in transit from Ze Germans. Looks like next week I'll have it going.


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## S​​usspect (May 12, 2017)

crembz said:


> Parts have started to arrive. Received the zocchi bomber today and the bonty XR5 29x2.6" front tyre. Stem has arrived also.
> 
> I'll keep my XR4 27.5x2.6" in the rear.
> 
> Wheels still in transit from Ze Germans. Looks like next week I'll have it going.


Very cool, keep us posted.

Although it's very different from your project, I have found the mullet works fine with my setup, no real downside beyond the heavier front wheel. The geometry feels right at home after two rides.

Hope your build goes well!


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## crembz (Feb 25, 2019)

Most of the parts have arrived so I set about building her up. Still waiting on the rear wheel (ocd had to have matching front/rear) but she's almost ready:









You can tell the difference in STA right away, I had to adjust the seat nose down slightly. Haven't had a chance to really ride anywhere other than the driveway but nothing feels 'off'. Front is definitely easier to pick up and that massive 29x2.6 in the front seems pretty ominous.

Looking forward to setting out this weekend. Hopefully the matching rear wheel arrives and I can finish it off and put the tools away.


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## crembz (Feb 25, 2019)

So I managed to get out over the weekend so I thought I'd post my impressions.

I ran a familiar trail I've done several times, it's a 16km blue xc trail with lots of technical climbs, tree roots, loamy+loose over hard surfaces. There are several fast downhill sections, with berms, switchbacks and smaller jumps and a double black section with some 1m+ drops. 

I pr'd most of the descents by a fair margin and the bike felt right at home and confident. I struggled as I always do with the climbs. My times didn't look good on the climbs, I didn't pr any of them, however, I did beat my previous times on the same bike. My pr times were on my xc bike.

Overall I managed close to a 10% faster time than my previous best attempt. 

One thing that was noticeable was the weighting on the rear during the climbs, especially seated. I had to consciously change my body position to be more forward than I would normally.

I'll need to do a few more rides before I can say I'm sticking with it but first impressions are good.


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## PuddleDuck (Feb 14, 2004)

crembz said:


> So I managed to get out over the weekend so I thought I'd post my impressions.
> 
> I ran a familiar trail I've done several times, it's a 16km blue xc trail with lots of technical climbs, tree roots, loamy+loose over hard surfaces. There are several fast downhill sections, with berms, switchbacks and smaller jumps and a double black section with some 1m+ drops.
> 
> ...


Great feedback, thanks :thumbsup:

Regarding having to _"consciously change my body position to be more forward than I would normally."_

Did you lower your bars and slide your saddle forward on it's rails to compensate for the higher bars & slacker HTA/STA?


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## crembz (Feb 25, 2019)

I lowered the bars 5mm and also dropped the stem down 5mm. I tilted the seat but left it in the same position on the rails. I might check my seat-bb measurement tomorrow and adjust it to my usual 29cm off the rear of the seat.


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## S​​usspect (May 12, 2017)

crembz said:


> My times didn't look good on the climbs, I didn't pr any of them, however, I did beat my previous times on the same bike. My pr times were on my xc bike.


What's not to like? Sounds like you did better than you did before on this bike, which for climbing is a pleasant surprise...

You may find sliding the seat forward even just 5-10mm on the rails will help the seated position feel more balanced.

But looked at strictly from a performance perspective, it sounds like it works just fine!


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## crembz (Feb 25, 2019)

Yes I can't disagree, the numbers tell me I did better on this build than I have in the past. And that was after 2 months not riding due to work/weather/laziness. I'm not one to chase times though, it's more about how much fun did I have, how good did it feel?

Subjectively it felt more stable and confident downhill, heavier up, less lively but rolled better over stuff. Most noticeable I suppose because it's a hardtail, the rear felt bouncier over obstacles with the big volume 2.6. I'm guessing that because of the shift in weight towards the rear.

I'm actually thinking of going to lower volume 2.6" tyres to try and get that liveliness back.


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## S​​usspect (May 12, 2017)

crembz said:


> I'm not one to chase times though, it's more about how much fun did I have, how good did it feel?


Sure, I can get that, and that's a good way to approach things.:thumbsup:



crembz said:


> Subjectively it felt more stable and confident downhill, heavier up, less lively but rolled better over stuff. Most noticeable I suppose because it's a hardtail, the rear felt bouncier over obstacles with the big volume 2.6. I'm guessing that because of the shift in weight towards the rear.
> 
> I'm actually thinking of going to lower volume 2.6" tyres to try and get that liveliness back.


You seem to have a keen sense for riding dynamics. I can see how the shift in weight could affect subjective "playfulness", even if it does enhance performance... It'll be interesting to see if sliding the saddle forward a bit helps balance that out.

And as you may know, air pressure can be the key with big volume tires, even 1-2 psi on the wrong side of perfect can make things feel bouncy (or give you rims strikes). You may find letting out a little air will reduce the bounce, and let you keep the current tire, ymmv.


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## crembz (Feb 25, 2019)

I still consider myself an beginner tbh, I haven't spent enough time on many other bikes to compare and contrast riding dynamics so take what I'm saying with a grain of salt. I'm just an analytic technical personality by nature, drives my wife nuts lols.

Yeah it's the needing to dial tyre pressure to near perfection that really annoys me. There's so much going on between air forks, geometry and body position that I'd rather a set and forget tyre that isn't going to be super fussy. I have some rimpacts inbound to try dampen the bounciness but I have read they don't quite provide the sidewall supper on the higher volume 2.6s. Wait and see


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## S​​usspect (May 12, 2017)

crembz said:


> Yeah it's the needing to dial tyre pressure to near perfection that really annoys me. There's so much going on between air forks, geometry and body position that I'd rather a set and forget tyre that isn't going to be super fussy. I have some rimpacts inbound to try dampen the bounciness but I have read they don't quite provide the sidewall supper on the higher volume 2.6s. Wait and see


For whatever reason, I like messing with tires. Other aspects of bike maintenance/repair may bedevil me, but I like tires. And once I've found the sweet spot for air pressure (basically as low as I can go without getting rim strikes or squirm), all it takes is a quick psi check before each ride.

I've never ridden 27.5x2.6, but for reference, I'm about 165 necked, and seem to get by with about this psi F/R:

29x2.4 - 18/22
29x2.6 - 16/19
29x3.0 - 13/15
27.5x2.8 - 14/17

Tubeless, of course. YMMV.


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## crembz (Feb 25, 2019)

S usspect;14195429 said:


> For whatever reason, I like messing with tires. Other aspects of bike maintenance/repair may bedevil me, but I like tires. And once I've found the sweet spot for air pressure (basically as low as I can go without getting rim strikes or squirm), all it takes is a quick psi check before each ride.
> 
> I've never ridden 27.5x2.6, but for reference, I'm about 165 necked, and seem to get by with about this psi F/R:
> 
> ...


What's your process to dial in pressures? Find a short section on single track and ride up and down tweaking every run?


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## S​​usspect (May 12, 2017)

crembz said:


> I'm just an analytic technical personality by nature, drives my wife nuts lols.


Yeah, I can see that lols. _I hear you Mrs. Crembz!_ jk



crembz said:


> What's your process to dial in pressures? Find a short section on single track and ride up and down tweaking every run?


No, nothing that scientific... I probably just googled it to see what other guys my size are running, set it there and went for a ride. If along the way it squirmed or struck aluminum, I'd add 1-2 psi. Or, on the other hand, if it bounced I'd drop the pressure.

(honestly I don't think I've ever struck a rim other than the one time I destroyed a tire.. not sure which happened first).

Recently I was running 29x2.6 at 20 psi rear on my FS bike. When I swapped those wheels onto my hardtail, I began to notice the rear tire was a little bouncy. I guess the suspension had been masking it. So I dropped one psi to 19 and it improved noticeably. Not sure if I could have gone lower, didn't want to risk it. Moral is bounce may be most noticeable on a hardtail.

If I was setting up a 27.5x2.6, I'd probably start at 21 psi on the rear and see what happened (again ymmv depending on weight, tire, rim width etc.)
Do you know what pressure you've been running?


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## crembz (Feb 25, 2019)

I had been running 21/19 psi on lower volume tougher casing 2.6" before I mulleted the bike. I probably shouldn't have changed so much at the same time. Unfortunately I sold the minions before I tested these bontis.

The tyrewiz app suggests a very low 16psi based on my weight and tyre width. At that pressure I can feel the tyre shifting just using my hands. My understanding is go as low as you can before feeling squirm or rim strikes. 

Once it stops raining, I'll take my gauge and pump out and do some testing. Hasn't stopped raining for a week. The closest trails are full slop.


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## S​​usspect (May 12, 2017)

crembz said:


> I had been running 21/19 psi on lower volume tougher casing 2.6" before I mulleted the bike. I probably shouldn't have changed so much at the same time. Unfortunately I sold the minions before I tested these bontis.
> 
> The tyrewiz app suggests a very low 16psi based on my weight and tyre width. At that pressure I can feel the tyre shifting just using my hands. My understanding is go as low as you can before feeling squirm or rim strikes.


Sounds like you're on it. If 19 bounces, bring it lower right?



crembz said:


> Once it stops raining, I'll take my gauge and pump out and do some testing. Hasn't stopped raining for a week. The closest trails are full slop.


That's a bummer. We had a wet spring around here, but trails are starting to get downright dusty this last week. Sometimes there's nothing you can do but wait it out. Would your wife let you build an indoor rock garden? :idea:


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## crembz (Feb 25, 2019)

I got deathstares when I moved the car out of the garage to make space for the bike(s). I don't like my chances of an indoor rock garden lol.

To add to that, I have bike n+3 on its way so indoor rock garden = no freaking chance hahaha


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## RockySpieler (Jan 8, 2012)

Hi crembz
I am building up a scout and am a mullet fan. Did you make any more changes to the set up?
I think you have it set up with Marzoochi Bomber Z1 29" 130mm. 
Did the front end always feel light when climbing, there was a suggesting to move seat forward (change c.o.g)?
Thanks


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## crembz (Feb 25, 2019)

Hey mate, I did move the seat slightly and and ended up dropping my bar to try offset changes to reach and stack introduced by the mullet. Imo there's a lot of focus on the hta and sta when doing this but most forget to mention reach and stack. If you're in between sizes and opted for the smaller size I found the mullet can make the bike feel a little short. You can play with stem lengths and spacers if you want but I don't really like stems longer than 45mm.

I rode this for several months. Enjoyed it but unless you need the rear tyre clearance my conclusion is you should stick with a 29er for monster trucking terrain or a 650b if you you're more into jumps and popping of features. I ended up reverting back to a 650b setup. It's more fun that way I think.

If you want to do both maybe going to 27.5x2.8 is the answer.


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## RS VR6 (Mar 29, 2007)

Bike is a 140mm Banshee Spitfire V2.

I have an extra 29 fork so why not. The fork is 130mm and the front wheel is from my Following. The rear tire is a 2.6 and the front is a 2.35. Not sure how it'll ride.

The 27.5 up front was 150mm fork with a 2.6. tire. With the 29 and 130mm fork...it roughly puts my hands in the same spot as the 150mm 27.5 fork.

Bar height is pretty close to being the same...but I'm losing 20mm of travel.

Oh...the 29 Yari has a 51mm offset and I beleive the 27.5 Float 34 is a 46mm.

Sent from my iPhone using Tapatalk


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## crembz (Feb 25, 2019)

You can also adjust the dropouts on the banshee which could help level the bike back out if needed i.e. put it in the high position


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## _tarzan (Aug 10, 2014)

I have a mullet bike: 2017 Django 29 with 27.5 in the rear. In stock config its 130/120mm f/r. I wanted to keep the geo so I put a longer shock in the rear. Now it has the same geo (static) and 130/140mm f/r.

I think that's the way to go, keep same geo so you need to compensate the bb drop with longer shock or flip-chips and offset bushings. Problem with flip-chips is they usually don't alter the bb height enough for this. Changing the rear to 27.5 from 29 drops the rear axle 19mm and BB more than half of that so in the case of the Django the BB drops ~13mm with just a wheel change.

So, to drop the rear axle (and lift the BB) the same amount as the difference in wheel radius, I needed to calculate: every mm of shock stroke gives 2,727 mm of travel (120/44=2,727), then divide 19mm with that, 19/2.727= 7. In other words 7mm more stroke and shock length needed. Swap 184x44 shock to 190x51, and you have almost exactly the same geo, I could still make the fork 140 to match the rear and compensate for that little bit extra BB drop I still have but I like the bike this way. I don't want it slacker and shorter. With the 27.5 wheel I use a slightly bigger tire also.


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## David R (Dec 21, 2007)

I'm big fan of having 10-20mm more trvel in the front, can't imagine it the other way round. How does the bike feel? Still balanced or ??


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## _tarzan (Aug 10, 2014)

I'd say it's allright. Basic trail riding feels good. Last year in Åre bike park it felt a bit harsh in the front in high speed stuff but I wouldn't say its unbalanced. Depends a lot on the tune of the shock of course. Rear feels really good and controlled. The newer model is specced with 140 fork so I could go that way but because I also use the 29 in the rear I think its a better compromise this way.

I'd say that on general trail riding it's a bit slower as a 79er if you count both ups and downs, especially on flatter terrain. On DH stuff it's noticeably faster for me because I'm not that tall and the maneuverability increases a lot with the smaller rear wheel. I can ride steep and technical stuff safer and with more confidence. These are obvious things I think and you need to choose what is more important for you (if you're not 6' tall that is). If I lived somewhere with long climbs and tech descents I'd keep it as a 79er always but I live in an area where descents are typically 5-30 secs and not that steep so I use both setups.







[HR][/HR]


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## Debido (Oct 24, 2019)

I mulleted my Intense Recluse, the head angle changed 0.7° with the same travel fork. Actually improved my climbs because of the bigger rim rolling over the terrain, even with the slightly steeper head angle and it goes downhill like a weapon. People saying that it increases your head angle by up to 3° are full of it. Simple maths can work out the difference in angle it will make before you try it and the whole purpose of a mullet isn't to XC in any case, the whole purpose is to send that mofo...


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