# Fixed Gear: Improving Chainline Options



## retspih (Mar 1, 2012)

So I put together a fixie the other day and got a slightly narrower bottom bracket so the chainring is fairly close to the chainstays. I have an All-City Standard fixed hub in the rear.

My chain is making a ton of noise and I really feel it when I turn the cranks. Took off the chain and spun with just the cranks in the BB, and everything was smooth. All arrow point to the offset chain.

So here's the issue. I'm just a few mm away from my chainstay with my current chainring. On the hub, there aren't any extra threads for a spacer for the cog.

How can I improve my chainline?


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## JCavilia (Sep 12, 2005)

So if I understand you correctly, the cog is too far left, so you want to move it to the right?

You can probably re-space the axle. Since you have track nuts, there's probably enough threads for you to do it without completely disassembling. Remove spacers on the right, add on the left. the whole hubshell will be moved to the right.

Then you have to re-dish the wheel, because the rim will now be off-center.


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## retspih (Mar 1, 2012)

JCavilia said:


> So if I understand you correctly, the cog is too far left, so you want to move it to the right?
> 
> You can probably re-space the axle. Since you have track nuts, there's probably enough threads for you to do it without completely disassembling. Remove spacers on the right, add on the left. the whole hubshell will be moved to the right.
> 
> Then you have to re-dish the wheel, because the rim will now be off-center.


Yes, I want to move the cog farther right. And that all makes sense and everything, but I don't believe I have any spacers on the right. All it is is the hubshell, two nuts, then the outer nut. According to the manufacturer, those two inner nuts need to be tightened against each other which doesn't give me any leeway for removing/adding spacers right? maybe i'm missing something big here.


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## UrbanPrimitive (Jun 14, 2009)

It seems odd that there wouldn't be any spacers, but I haven't seen an All-City hub in person to know. Are you using 3/32" or 1/8" parts? 1/8" chains tend to be stiffer laterally, so if you can switch to 3/32" that may help a wee bit. You might also win a little space by moving your chainring to the inside of the cranks, rather than the outside. Try a dry fit to see if you can clear your chainstays that way. The worst case scenario that I'm aware of would be to crimp or dimple your chainstay to give your chainring clearance. It isn't a pretty solution, but it can get the job done.


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## retspih (Mar 1, 2012)

UrbanPrimitive said:


> It seems odd that there wouldn't be any spacers, but I haven't seen an All-City hub in person to know. Are you using 3/32" or 1/8" parts? 1/8" chains tend to be stiffer laterally, so if you can switch to 3/32" that may help a wee bit. You might also win a little space by moving your chainring to the inside of the cranks, rather than the outside. Try a dry fit to see if you can clear your chainstays that way. The worst case scenario that I'm aware of would be to crimp or dimple your chainstay to give your chainring clearance. It isn't a pretty solution, but it can get the job done.


I'm using an 1/8 chain, and I've tried to put the chainring on the inside...not a good fit.

I thought about denting the frame. but the reason I built up this bike was to get away from my much too dented previous frame. Seems a bit ironic to dent up the new frame haha

Ummm maybe I'm misinterpreting this whole spacer thing.can you see anything from the pictures i posted?

or this link: https://allcitycycles.com/images/products2/HU4723.jpg


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## mudge (May 15, 2010)

If you're not running a 3/32" cog, that's your first issue. Why? 'Cause without one, you can't run a 3/32" chain. For years I've run a double-chainring setup w/ a flip-flop hub, one cog on one side and a Surly dingle cog on the other. With a 3/32" chain I can run either chainring with any of the three cog choices and have no problems whatsoever with the chainline causing excess noise.

Even if you're running a perfect chainline, a 1/8" chain will run noisier on a 3/32" chainring than a 3/32" chain will. If you're not an world-class track sprinter or kilo specialist, you do not need a 1/8" chain.

If none of that works for you, just put a 10sp cassette spacer behind the cog. Use an aluminum spacer, not a plastic one. The torque on the cog will eventually crush a plastic spacer.


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## onespeedbiker (May 28, 2007)

Most fixed gear bikes with 120mm stays are designed around a 42mm chain line as is your hub. I would be concerned that your frame might be bent. It's almost impossible to tell from the pictures, but the possibility is very high. There is a very easy ways to determine this; 1st mount the wheel so the hub axle is push all the way back in the fork ends (or at least at the same point on both sides; the wheel should be perfectly centered, if not the frame is bent. #2 using the Sheldon Brown string method Bicycle Frame/Hub Spacing

If the rear stays are tweaked and there are no cracks in the frame you could probably cold set the frame using the Sheldon Brown 2x4 method Bicycle Frame/Hub Spacing (instead of spreading the stays you would be moving them both to the right side keeping the spacing the same).


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## frankdatank1337 (Jul 25, 2010)

It could just be your chain. I ran a Izumi V Super Toughness chain for its durability but the noise it made was unbearable. Although, if it feels weird it could just be your chainline.
I was looking at the pic of your chain and if you are going to run brakeless I would recommend not using a quick link/power link and using a chain tool to connect your links directly (its much safer).


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## David Loving (Jun 13, 2008)

A phil wood bottom bracket allows for about 5mm or so adjustment of the axle. That and a 3/32 chain might do it.


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## UrbanPrimitive (Jun 14, 2009)

Sure enough, I'm not seeing the kind of spacers I'm used to in that image. Strange. There are a couple of other things to try that might eliminate some of your problem. The first is to ensure that all your parts are truly clean. I don't mean to be insulting, but sometimes stuff comes out of the parts bin and gets put together fairly nasty. That can cause some sticking which _can_ (not always) feel similar to a torqued chain. Also proper chain tension can make a big difference here. It's a fairly common mistake to put too much tension on the chain. There seems to be a myth that perfect chain tension has absolutely no slop and will run dead silent. Neither of these is necessarily true. Even riding fixed you may get _some_ noise. More importantly, you should actually have around 1" total vertical movement in the chain (+/- 0.5" up and down from its position at rest). If both of these factors are observed, a chainline within 1mm to 1.5mm of perfect should run pretty well with little noise and little to no extra drag.

If none of these options address your problem I don't know what else to suggest that doesn't involve a new purchase. A Formula rear hub can be respaced for chainlines other than 42 (mine is running at 43), a different crankset might get you a little closer (as would a shorter bottom bracket spindle), though then you run into the chainstay issue. Dimpling the chainstay might give you the room you need to achieve your chainline, but should be done carefully (I'd suggest using a rounded-off cold chisel or other form rather than directly hitting the frame with a hammer. It allows more accuracy).

Unfortunately this



onespeedbiker said:


> mount the wheel so the hub axle is push all the way back in the fork ends (or at least at the same point on both sides; the wheel should be perfectly centered. . .


only holds true if you know the wheel to be evenly dished. While it's likely to be true, I wouldn't modify my frame before checking the wheel for accuracy. You might have a mystery frame that just doesn't quite like the components you're putting on it. I wrestled for quite a while getting my Fuji (which was built specifically for riding fixed) to have a 42mm chainline, and eventually settled on compromising with a 43mm chainline, redished rear wheel, and sacrificing the flop of my flip/flop hub.


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## onespeedbiker (May 28, 2007)

UrbanPrimitive said:


> .
> 
> Unfortunately this
> 
> ...


I think you missed my point. First, no amount of redishing would accomplish anything; if you had to respace the hub on your Fuji, then the the hub was to far outboard, the OP's hub is to far inboard. The chainline is built into the frame and the hub is designed around it. The hub is as far right as possible on the axle (which is it's proper position) yet still it appears to be too far inboard and the chainring is 1 mm away from the chain stay so it also can go further left; no other adjustment is possible. The only possible solution would be to go with a smaller chainring (so he could mount the chainring on the inside of the chainring tabs)or bend the stays to the right to straighten the chainline. I gave the OP several options to check the straightness of the frame. Obviously Sheldon Brown's string method is the best to determine if the frame is bent, but any redishing would have absolutely no effect on the position of the hub or the chain line and any respacing of the hub on the axle (which would require redishing) would be moving the hub in the wrong direction. .

edit: As far the friction and noise, I posted on the OP's other thread that the likely cause is a too tight chain and a chainring that is not centered on the crank..


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## retspih (Mar 1, 2012)

First, I appreciate a lot of the thoughtful responses.

I think I may have screwed up. I actually may be running a 3/32. I'm getting myself all confused now...and am unfortunately away from the bike for the next week. I'll take measurements when I get back. I seem to remember I'm running the narrower chain which would obviously be 3/32, apparently my math was struggling when I said 1/8 because 3/32 is less than 1/8. Okay I'll shut up with my excuses and leave it at that I'll check next week!

UrbanPrimitive, I've just built up those wheels myself, and dish in the rear was actually pretty impeccable, I was impressed with myself haha. I'll check to see if the frame is bent although it's a totally new frame. It's one of those Eighthinch scramblers, the $150 buys you frame, fork, headset, seatpost kind. Really cheap, so misaligned frame certainly isn't out of the question. a slightly misaligned frame would buy me a ton of lateral movement of the entire hub when corrected. When I installed the wheel, i remember tightening down on the hub outside nuts so it would square itself up made the wheel slightly offset. I'm hoping that's the case and the frame is actually just misaligned (why should I ever hope for this to be the case...ugh) and I can just square it up and have my chainline issues squared (hah) away.


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## retspih (Mar 1, 2012)

frankdatank1337 said:


> It could just be your chain. I ran a Izumi V Super Toughness chain for its durability but the noise it made was unbearable. Although, if it feels weird it could just be your chainline.
> I was looking at the pic of your chain and if you are going to run brakeless I would recommend not using a quick link/power link and using a chain tool to connect your links directly (its much safer).


No noise on the same chainring/cog/chain setup from my previous steed. And re: quick link, it's so damn convenient!! but you're right. I should probably switch back to using a chain breaker and normal chain.


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## onespeedbiker (May 28, 2007)

retspih said:


> First, I appreciate a lot of the thoughtful responses.
> 
> I think I may have screwed up. I actually may be running a 3/32. I'm getting myself all confused now...and am unfortunately away from the bike for the next week. I'll take measurements when I get back. I seem to remember I'm running the narrower chain which would obviously be 3/32, apparently my math was struggling when I said 1/8 because 3/32 is less than 1/8. Okay I'll shut up with my excuses and leave it at that I'll check next week!
> 
> UrbanPrimitive, I've just built up those wheels myself, and dish in the rear was actually pretty impeccable, I was impressed with myself haha. I'll check to see if the frame is bent although it's a totally new frame. It's one of those Eighthinch scramblers, the $150 buys you frame, fork, headset, seatpost kind. Really cheap, so misaligned frame certainly isn't out of the question. a slightly misaligned frame would buy me a ton of lateral movement of the entire hub when corrected. When I installed the wheel, i remember tightening down on the hub outside nuts so it would square itself up made the wheel slightly offset. I'm hoping that's the case and the frame is actually just misaligned (why should I ever hope for this to be the case...ugh) and I can just square it up and have my chainline issues squared (hah) away.


Have you tried loosening the chain to see if the friction goes away? If indeed the problem is with a uncentered chainring on the crank, you will see the chain continually loosen and tighten as you turn the cranks.


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## FBinNY (Jan 24, 2009)

Just a thought, based on the broadside picture. I suspect your chain is too tight, which is more important than perfect chainline.

The amount of chainline error isn't that great and shouldn't be noisy or felt in the pedals. After all, derailleur chains go through far worse S-bends.

OTOH- I don't see any sag in the chain. On a single speed or IGH chain it's important to leave a bit of slack in the chain so the only tension is in the upper loop caused by pedal pressure. 

You should have enough slack for 1/8"-1/4" free vertical movement in the middle of the lower loop. Or you can check for free backlash movement of the cranks and the ability to see the transfer of the slack from the upper to lower loop.

Since sprockets aren't perfectly concentric, measure for slack at the tightest position. 

Again, it's just from the photo, but I suspect your problems will disappear if you move the rear wheel forward a smidge.


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## retspih (Mar 1, 2012)

I have played around with the slack, and it still seems to be there. Something I didn't try, though, was centering the chainring and measuring slack in its tightest position. could be a good thing. also, centering the chainring could alleviate some of those high spots.


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## retspih (Mar 1, 2012)

Alright so I centered the chainring. Definitely were some high spots and so I smoothed a lot of it out. It's still fairly noisy. As far as I can tell, the dropouts are aligned to the rest of the frame. Any other ideas?

What does riding on it like this do? Does it weaken the chain? I'm very concerned about safety because I'm riding in NYC and avoid using my front brake (I mean...did you see the rims I laced up?)

Thanks guys (and gals)


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## JCavilia (Sep 12, 2005)

retspih said:


> Alright so I centered the chainring. Definitely were some high spots and so I smoothed a lot of it out. It's still fairly noisy. As far as I can tell, the dropouts are aligned to the rest of the frame. Any other ideas?
> 
> What does riding on it like this do? Does it weaken the chain? I'm very concerned about safety because I'm riding in NYC and avoid using my front brake (I mean...did you see the rims I laced up?)
> 
> Thanks guys (and gals)


Post another side-view picture. I suspect your chain is still too tight. FB was correct in his observation; in your original picture it looks way too tight.

If the tension is too high, the chain will wear faster than normal, but that doesn't mean it's more likely to actually break. That's a very rare occurrence in a properly-assembled chain. Of more concern with excessive tension is accelerated wear on ring and cog - and maybe even wheel bearings. 

Why do you avoid using your brake? Nobody can see whether you do, so you don't get any coolness points (unlike having no brake). ;-)


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## retspih (Mar 1, 2012)

JCavilia said:


> Post another side-view picture. I suspect your chain is still too tight. FB was correct in his observation; in your original picture it looks way too tight.
> 
> If the tension is too high, the chain will wear faster than normal, but that doesn't mean it's more likely to actually break. That's a very rare occurrence in a properly-assembled chain. Of more concern with excessive tension is accelerated wear on ring and cog - and maybe even wheel bearings.
> 
> Why do you avoid using your brake? Nobody can see whether you do, so you don't get any coolness points (unlike having no brake). ;-)


I can post another picture tonight. after I centered the chainring (Sheldon Brown's method), tension all around seems pretty good, about 1/2" play.

As far as wear on my chainring/cog, I'm about change my gearing in a few months when I build my own frame, so it just has to last me that long.

And...the wheels. They don't have a machined sidewall! So as soon as the black wears off, it will be quite noticable that I braked. uh oh.


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## Dave Hickey (Jan 27, 2002)

Late to the game with reply....Good advice given so far..

Couple of thoughts.... 

Do you have a smaller ring you can experiement with? If the BB spindle length you are using is designed for the crankset, _most _road crank conversions will work better with the ring on the inside position...It will give you a chainline closer to 42mm....I have a similar frame and the design of the stays doesn't allow that large of ring to be used on the inside position...The outside position gave me a chainline closer to 47mm.... too far off for a quiet drvetrain...

looking at your bike, a smaller ring(42T) on the inside is what I would try

If you really want a quiet drivetrain, you need to figure out a way to get the ring closer to the stay..Since the large ring rubs on the inside position, you'd need a smaller ring(due to way the stays flare out) .... If that works, buy a smaller cog to to match the smaller ring to give you the same gearing as your current setup

Another option is a shorter spindle but you still won't get the ring, in the outside position, as close as using the proper BB length and the ring on the inside


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## onespeedbiker (May 28, 2007)

I have not read anything in this post to indicate you have checked if the stays are lined up properly. it is very simple, just turn the frame upside down and do this http://sheldonbrown.com/frame-spacing.html#symmetry. Until you check this out, any other fix will be pointless (except centering the chainring):thumbsup: If your stays are out of alinement it could account foe some of the noise; remember that noise you here when you are shifting just before the chain derails and you'll understand what I mean. 

In regards to your chain, make sure you adjust the tension when the chain is at it's most taunt point. If you tension the chain at it's most loose point, the noise will be substantial and you'll destroy your hub..


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