# Considering going to a single sprocket on the crank? Pros vs Cons??



## Kingsnake (Sep 27, 2010)

I have been riding for a little over a month now and put in just over 100 miles on my bikes (30 on the old GT and 70 on my 29er) 
I find that the last week and a 1/2 of riding which consist of 6miles flat sandy single track, about 25miles of streets with parking garages thrown in, and a trip to san angelo state park. I have only been using the 44 tooth sprocket on the front and have felt no need to change to an easier gear... the rear cassette is getting all the action.
So basically I am thinking about going to a single sprocket on the crank... most likely a 40 or 42 tooth sprocket.
heres what I have come up with so far in pro's...
less weight
1 less derailer to adjust
cleaner look on the handle bars.

What are the cons here? I havent been riding that long and Im afraid that I might be missing something
Thanks


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## wickerman1 (Dec 24, 2003)

Depending where you live and what type of terrain you ride in. I live in BC, it is mountainous,and I only use granny gear on very steep stuff, otherwise its mid ring only. If you have a ton of climbing to do keep it at 2, if not, then strip it down.
42/44 for one ring, might as well get a cross bike LOL.
get a 36 or 38 mid ring, I dont even think you can put a 42/44 in the mid position, where it needs to be for a one ring set up.


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## tihsepa (May 15, 2009)

I dont own a bike that shifts on the front. All mountain bikes are 32 up front. Either single speed or 1X10 or 1X9. Heck my 1X9 ala carte is even running pauls thumbies. 

The only con is you count on the front derailuer to keep the chain on. I run a paul keeper to keep the front in check. It works out fine. 

Here in the midwest I have no problem with a single up front and even a single speed in most places we ride.


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## khardrunner14 (Aug 16, 2010)

I run 32t up front only. I hated dealing with a front derailuer that was needing something or other to be tweaked so it wouldn't rub. I love the simplicity and clean look as well. I live in pretty hilly Pa and can do just fine with my 1x8. Just less to mess with. Bonus is weight reduction.

As for a chain keeper, I'm too poor to be able to afford a nice keeper set up. So I left the FD on and modified it to allow a full range of gears in the rear with no rubbing. It's fairly light an I have yet to lose the chain.


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## Kingsnake (Sep 27, 2010)

That is kinda what I was thinking... I live in West Texas... Permian Basin to be exact. Big mountainess climbs are not something I am going to see often. At san angelo and a few other places around there are some decent short steep climbs.
Ill prolly ride for atleast another month before I make any decisions... and even if I change it its not like there is no going back.


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## Clones123 (Apr 29, 2010)

You'd first want to see if you've got enough chainstay clearance to fit a 40t or 42t in the middle ring position. You must have seriously strong legs. I've seen people pondering 34t vs 36t on a 1x9 setup but never 40t vs 42t.

The next issue is keeping the chain on. Not a huge problem if you can always halt pedaling over big bumps but that can be difficult to do consistently. Personally, I'm stuck waiting on the Paul Love Components Chain Keeper to come back into stock at JensonUSA for my own 1x9 setup so I'm keenly aware of the issue. On the other hand, if you've got ISCG-05 tabs or at least an external bearing BB there are a couple of other options for chain retention devices - none of them are cheap though. What is perhaps the least expensive alternative is to use inner & outer bashguards to create a pulley-like effect - BBG Bash Guards, for instance.

Oh and if you want a stand-alone chain ring without ramps, gates or pins, look around and you'll see that they're pretty much all aluminum and way more expensive than you'd think for a plain sprocket.

Man, that avatar is disturbing.


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## Kingsnake (Sep 27, 2010)

I dont really think I am that strong... just cant imagine needing all those gears. My bike is a specialized comp 29er. Its got a 44 tooth now mid ring is a 32. I used the 32 alot when I 1st started riding but now I just dont use it, or atleast havent been in a situation where I have needed it.
paul is selling a set up like that Im thinking http://paulcomp.com/mtcrank.html
they even have a 48!

Can you guys that are running singles up front post up some pics of your set up?
Thanks


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## tyler243 (Oct 28, 2009)

All the 1x9 pics you could need are here: http://forums.mtbr.com/showthread.php?t=586175


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## Clones123 (Apr 29, 2010)

Kingsnake said:


> paul is selling a set up like that Im thinking http://paulcomp.com/mtcrank.html


Looks to me like that crankset is for single-speed only and doesn't accept a 9-speed chain...

_"The chain rings are machined out of 6.3mm thick aluminum plate; very sturdy. They are currently designed only to work with ⅛" chains (track and bmx)"_


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## Kingsnake (Sep 27, 2010)

Clones123 said:


> Looks to me like that crankset is for single-speed only and doesn't accept a 9-speed chain...
> 
> _"The chain rings are machined out of 6.3mm thick aluminum plate; very sturdy. They are currently designed only to work with ⅛" chains (track and bmx)"_


 Thanks Clones.I didnt read all the fine print....
But It looks like the MRP 1.X or the E13 XCX will work. The e13 says it will go up to a 42t.
I took a close look ar the bike last night. Im not possitive that I will be able to get a 40t on the center of the crank... it might work but would be tight. I realize that It would be best to have it on center but is there any problem with it being on the outside position? That is where the 44t currently is and it hasnt given problems.
That little problem aside.. It looks like I could simple remove the derailer etc, install the chain guide and a sprocket that will fit and be off to the trails... Right?
That is actually going to be cheaper than I thought... I was planning on having to replace the crank. the chain guides run about $45 for what Im wanting and sprockets arent to bad
Thanks again for all the help... My "Local" bike shop that Im willing to spend my money at is about 2 hours away so its nice to get alittle help from people that have dealt with this before


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## Montanamtb (Aug 5, 2010)

I NEVER use my large ring. Can I just take the ring off or do I have to buy a whole new crankset? I would love to shed the unnecesarry weight.


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## khardrunner14 (Aug 16, 2010)

You can take the ring off as long as you have something to help keep the chain on. FD would work fine depending on how you tune it.


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## Straz85 (Mar 20, 2009)

I can't imagine only having a 40 or 42t ring, I'm running 1x10 with a 32t ring. Although I am rarely on anything but single and double track, and the northeast is pretty hilly. I can't see ever going with anything larger than a 34t front though. That's with an 11-36 cassette.


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## Kingsnake (Sep 27, 2010)

I can see using the 32 tooth ring... but it make the easy gears on the rear cassette worthless. I want to come off the 44t that I am currently using to make life a little easier... 
11 32 44 
11-2.1 6.1 8.4 
13-1.8 5.2 7.1 
15-1.5 4.5 6.2 
17-1.4 4.0 5.4 
20-1.2 3.4 4.6 
23-1.0 2.9 4.0 
26-0.9 2.6 3.6 
34-0.7 2.0 2.7 

above is a pretty close picture of what the final drive ratio is on the bike. I would say based off the place that I am riding and what I am doing that anything less than about a 2.5 is worthless. lots of pedaling and not going anywhere. By the time that I get below 1.0 I would for sure be better to just get off and walk the bike. On the other end of the spectrum I think the 8.4 is more than I need. So Im thinking that if I drop to a 40t only my ratio would look like this...
40T
11- 7.7 
13- 6.5 
15- 5.6 
17- 5.0 
20- 4.2 
23- 3.7 
26- 3.2 
34- 2.5 
These numbers arent exact because I am not sure about the rear cassette on my bike but they are close. It just gives you a picture of how the gears overlap


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## Gabe3 (Mar 13, 2009)

what should one consider buying in order to go to a single sprocket in the front? cause I've been thinking about it for the past few weeks. I don't use the 1st and 3rd ever. and I'd like to take some weight off my 31 pound bike.


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## Straz85 (Mar 20, 2009)

Gabe3 said:


> what should one consider buying in order to go to a single sprocket in the front? cause I've been thinking about it for the past few weeks. I don't use the 1st and 3rd ever. and I'd like to take some weight off my 31 pound bike.


Something to keep the chain from jumping off the ring, some sort of chain guide/chain keeper. I have a bash guard on the outside and a chain keeper attached to the seat tube on the inside, works well, I haven't dropped the chain yet. Some people also just use a bash guard and and a SS chain ring, works fine for most XC riders. I think I'm going to give that a shot.

So, in conclusion, you need:

-Bash guard
-SS chain ring (optional)
-Chain guide (optional)

I lost 13oz when I did this conversion, a little less than I had hoped. That also included switching from SLX shifters to XT and M542 cassette to an M771.


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## Gabe3 (Mar 13, 2009)

what about just leaving the front derailleur on, how well would that work?


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## Kingsnake (Sep 27, 2010)

Gabe3 said:


> what about just leaving the front derailleur on, how well would that work?


 someone above said that is what they did. As long and you could get it adjusted to stay in the right place seems like it would work to me... it should function just like the stationary guides that mrp and e13 sell


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## khardrunner14 (Aug 16, 2010)

I set the set screws so that it was in the best position and would not move. Then I opened it up (screw in the back side) and slightly bent it so there would be no rubbing in top and bottom gears. The nice thing is, it's still adjustable and usable if I ever decide to switch back.


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## Straz85 (Mar 20, 2009)

Gabe3 said:


> what about just leaving the front derailleur on, how well would that work?


Well you need something to replace your big ring anyway...bash guard, so for another $10, you can get the N-Gear Jump Stop, looks 10x nicer than the FD and is lighter (only a couple ounces, but dropping a couple ounces for $10 is pretty damn good).


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## Gabe3 (Mar 13, 2009)

Straz85 said:


> Well you need something to replace your big ring anyway...bash guard, so for another $10, you can get the N-Gear Jump Stop, looks 10x nicer than the FD and is lighter (only a couple ounces, but dropping a couple ounces for $10 is pretty damn good).


I don't need a bash guard though, it would be wise to have but its not required is it?


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## Straz85 (Mar 20, 2009)

Gabe3 said:


> I don't need a bash guard though, it would be wise to have but its not required is it?


Pretty sure you'll need new chainring bolts. The same bolts hold your middle and large chainrings, so the bolts will be too long if you remove the large ring. Also, it will look kinda silly. You can get a BBG bashguard for $12, not much more than new bolts.


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## Gabe3 (Mar 13, 2009)

Straz85 said:


> Pretty sure you'll need new chainring bolts. The same bolts hold your middle and large chainrings, so the bolts will be too long if you remove the large ring. Also, it will look kinda silly. You can get a BBG bashguard for $12, not much more than new bolts.


a BBG bashguard is $18 with shipping. What about if I just got a mrp 1.x guide? I think I can get a used one cheap.


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