# Advice for seatstay clearance problems



## golden boy (Oct 29, 2008)

So I just finished building up my wheels for the 650b hardtail frame I built at UBI in February. I was concerned about rear wheel clearance, and rightly so. When I slipped the rear wheel in the dropouts, the tire rubbed on the drive side. Not so much that I couldn't spin the wheel, but rubbing nonetheless. The non-drive side has 1/8" of clearance. The seatstays are an S-bend model. The wheel is built with a Pacenti TL 28 rim and I mounted a Neo-Moto 2.1" tire.

I could go with a narrower rim/tire combo, but I'm betting I'd still have tire rub during actual riding conditions. Wheels flex laterally, no? Is it possible to crimp the inside of the seatstays after the frame is already built? If so, what methods are commonly used? Or am I just plain screwed, having cut my calculations too close, and need to chalk up this first frame build as a learning exercise?

Thanks in advance for your input.


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## j-ro (Feb 21, 2009)

Hmm, 1/8"..... thats 6 hard and 4 easy file strokes out of the dropout on the same side as the tire is touching with a 3/8" round file to make the wheel center.

make sure to cut 'up' and not forward so you don't mess with the chainstay clearance.


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## golden boy (Oct 29, 2008)

Thanks, J-ro. I do intend to do some careful filing of the drive-side dropout to correct the misalignment.

So what kind of stay clearance do folks design into their builds? I suppose it might depend on several factors, but let's just say a typical XC mountain bike?


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## j-ro (Feb 21, 2009)

1/2" is good but I'm just throwing that out there, I shoot for as much as possible at the chainstays within reason and then try to match that amount with the seatstays. It can just get unbalanced looking if there is a big difference.

Keep in mind this is at the sides and not over the top. That requires more clearance if you are using a bridge.

I think clearance needs have changed somewhat over time. With nearly everyone using disc brakes it seems ok to be a little tighter at the tire.

V-brakes and studs just seem to act like rebar to mud and build up much faster than a bare seatstay.


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## GrayJay (May 16, 2011)

It is still doable to crimp the CS in place. Make a wooden form (like a tube block) to support the outside of the SS and slowly crimp the inside with a vice. Check dropout width and alignment once you are all done with the crimp..


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## DWF (Jan 12, 2004)

Don't crimp if you don't absolutely have to. Cut the bridge out and reshape the stay using the technique describe above by GrayJay. Make up for the dropout dislocation by taking out a little of the second bend and reattach the bridge. If you're local, call Walt or myself and arrange a time to get a little 1 on 1 advice and maybe help?


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## Walt (Jan 23, 2004)

*Just thought I'd mention...*

One-on-one advice from me is payable in 6 packs, and soon, diaper changes. Preferably both.

To the OP - it sounds like you might want to start over. 1/8" *total* clearance is really way too little - <2mm on each side of the tire, even if it's centered, is going to mean rub when you get the wheel a tiny bit out of true, or corner hard, or get out of the saddle and sprint.

You could certainly crimp the stays (as noted by others, remove the bridge) but if you're going that far, I would actually just remove the seatstays and do them over (you can fix your minor misalignment that way too without any need for dropout filing). A little more work, but I think you'll be happier with the end result, and it's more practice for #2!

BTW, post up some pics of your frame/bike! First frames are awesome, even if you wish you'd done practically everything differently (I'll get a picture of mine sometime and everyone can point and laugh).

-Walt



DWF said:


> Don't crimp if you don't absolutely have to. Cut the bridge out and reshape the stay using the technique describe above by GrayJay. Make up for the dropout dislocation by taking out a little of the second bend and reattach the bridge. If you're local, call Walt or myself and arrange a time to get a little 1 on 1 advice and maybe help?


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## golden boy (Oct 29, 2008)

I think I agree with Walt. I really need to re-do the seatstays entirely if I really want to ride this frame. I've been looking at different bikes at the shop I work at today and most have between 1/4" - 1/2" per side. There's my rule of thumb (actually "finger"): I should be able to stick or nearly stick my index finger between the tire and the stay.

I will indeed post some photos soon. I wanted to get my fillets finish-filed first. Say that 10x fast.

And yes, I am local. I don't yet have my own framebuilding gear so I would love the opportunity to work with one of you guys on this project. I'll be in touch...


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## vulture (Jan 13, 2004)

Walt said:


> One-on-one advice from me is payable in 6 packs, and soon, diaper changes. Preferably both.
> 
> BTW, post up some pics of your frame/bike! First frames are awesome, even if you wish you'd done practically everything differently (I'll get a picture of mine sometime and everyone can point and laugh).
> 
> -Walt


 sounds like a fun thread, Post Your First. Pointing out what's wrong is encouraged.


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## j-ro (Feb 21, 2009)

vulture said:


> sounds like a fun thread, Post Your First. Pointing out what's wrong is encouraged.


Hey, no need for pictures of mine. You can see that the canti studs are on backwards from outer space


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## jgerhardt (Aug 31, 2009)

golden boy said:


> Thanks, J-ro. I do intend to do some careful filing of the drive-side dropout to correct the misalignment.
> 
> So what kind of stay clearance do folks design into their builds? I suppose it might depend on several factors, but let's just say a typical XC mountain bike?


The first frame I built (from UBI) had the chainstays AND seatstays too close together (hey, at least I was consistent). They probably had less than an 1/8" on either side. It rode fine with a Specialized Captain 2.0 on the rear. It would only rub when I was cranking up a long hill.


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## Smudgemo (Nov 30, 2005)

Walt said:


> One-on-one advice from me is payable in 6 packs, *and soon, diaper changes.* Preferably both.
> 
> -Walt


You have no idea, son...


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## jay_ntwr (Feb 15, 2008)

golden boy said:


> There's my rule of thumb (actually "finger"): I should be able to stick or nearly stick my index finger between the tire and the stay.
> .


That's how I measure it too. Index finger to the first knuckle--whatever that is...


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## coconinocycles (Sep 23, 2006)

vulture said:


> sounds like a fun thread, Post Your First. Pointing out what's wrong is encouraged.


Mine is on the shop wall - keeps you humble - what a POS..........cool, but a POS none the less.

Anyone else here think people are going overboard on crimping stays? 
I see some that must be crimped so that the stay must be 5mm thick at the crimp - makes me think it's flexy & going to break when I see that.
- Steve Garro, Coconino Cycles.


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## golden boy (Oct 29, 2008)

DWF said:


> Don't crimp if you don't absolutely have to. Cut the bridge out and reshape the stay using the technique describe above by GrayJay. Make up for the dropout dislocation by taking out a little of the second bend and reattach the bridge. If you're local, call Walt or myself and arrange a time to get a little 1 on 1 advice and maybe help?


The frame is fillet-brazed brass, and the bridge and other braze-ons are done with silver solder. My wife is a silversmith and has an acetylene torch (no Oxygen). Couldn't I just heat up the silver and remove the bridge?


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## golden boy (Oct 29, 2008)

Has anyone ever used the Hozan professional frame/stay spreader? I just came across it in the United Bicycle Tool catalog. Not sure if it would work on my seat stays since what they really need is more bend where the tire runs between them.


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## coconinocycles (Sep 23, 2006)

golden boy said:


> Has anyone ever used the Hozan professional frame/stay spreader? I just came across it in the United Bicycle Tool catalog. Not sure if it would work on my seat stays since what they really need is more bend where the tire runs between them.


You bet! 
It will spread the stays if it has to destroy the tubes or break the welds to do it. 
Good for say, Schwinn cruisers and mild steel. 
- Steve Garro, Coconino Cycles.


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## golden boy (Oct 29, 2008)

Yeah...I figured it was a hack tool. I had already envisioned my stays popping off of the seat tube.


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## golden boy (Oct 29, 2008)

*Some photos, finally*

Nothing fancy, but it's a whole lot better than nuthin'. Note the dimples on the inside of the seatstays. Gives me 1/8" clearance on either side of the 2.1" tire. Not great, but good enough to finally build up and ride!


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## febikes (Jan 28, 2011)

Overall the looks good, congratulations on your first build.

For your future frames, I recommend a smooth arc to avoid the dimple. Don't take this for more then it is worth but once you flatten part of the tube it becomes much weaker.

Check out this video to see how a chainstay fails at a dimple point.
Failure Testing #2 - YouTube

My guess is that unless you ride the frame crazy rough your dimples will be fine but it's something to think about for next time around. That said the forces on a bike are not similar to the youtube link so really I think you are going to be fine even with some fairly rough riding. Get some paint on that puppy, do some riding, then build the 2.0 version.


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## golden boy (Oct 29, 2008)

Thanks, Mark. The dimples were not planned, but turned out to be necessary after the initial build. I certainly will design more clearance into frame 2.0. My next frame will be designed in Alibre PE which I recently purchased. 3D baby, no guesswork on clearances next time!

I'm very light on gear so I'm not too worried about breaking the stays. But if it happens, that's OK. It is my first frame, after all. All the more reason to start on the next one. I'll post more pics as I paint it and build it up.


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## febikes (Jan 28, 2011)

It looks like you may still need to put a brace to support the rear brake forces. It's going to be great to get your first bike complete. It could be that the tubular brake support brace is not needed with the integrated dropout you are using.

(edit); I think you will be fine with those dropouts.


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## Eric Malcolm (Dec 18, 2011)

Firstly, well done. You could tidy up the pits/blenishes with silver - it won't heat up the brass enough to upset the work you've done.

Second, you have a butt jiont at the seat stay, and a slotted/tongue on the fork end. It would very easy to simply heat up and remove each stay an replace with new ones, rather than both leave as is or crimp and weaken it some more.

You have a good frame that just needs a good fix. When we all start out, and even as experience increases, there can be a bad day, and you simply got to go back and 'put it right'. Rather than do second best, seek perfection. You are so close.

Eric


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## golden boy (Oct 29, 2008)

Re-brazed the cable stops to the seatstays after dimpling. I tried adding silver to the pit in the BB area, but I guess my wife's acetylene torch could not generate enough heat to make the silver stick to the brass. Oh well, moving on...

I primered and painted the frame this weekend. I will sand the paint tomorrow night and apply the final clear coat. Assembly to begin later this week! I'll start a new post with photos.


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