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Pisgah2000

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Discussion starter · #1 · (Edited)
I searched around a bit and found some information, but would like some more. Has anybody added dimples to chainstays to add a little bit of tire clearance? This would be on a steel frame. I sort of impulse purchased a frame, and it doesn't quite live up to the specs. It's supposed to clear a 32, and while a 31.9mm wide tire fits and spins with about 1mm of clearance on either side, it's not really ideal. One ride resulted in rubbing paint. There's about 34mm of clearance between the stays at the widest point on the tire.

This is before the tire swelled a bit:

Image


I have a 30 on it now, and it's slightly better, but I didn't buy this to run a 30.

How realistic is it to add dimples to an already built and painted frame? Will it damage anything? Has anybody done this as a DIY? I know it'll void the warranty, but that's OK. I did come across a builder that added chainring clearance to a completed frame with shaped wood and a clamp, and that turned out well.

Or is this one of those "sell it and buy the right frame" sort of deals?
 
Sell the frame. If you modify the frame you will also change the structural properties and increase your risk of a failure-crash, it's not worth the trouble. Pushing a bike out of the woods sucks..
 
How realistic is it to add dimples to an already built and painted frame? Will it damage anything? Has anybody done this as a DIY? I know it'll void the warranty, but that's OK. I did come across a builder that added chainring clearance to a completed frame with shaped wood and a clamp, and that turned out well.

Or is this one of those "sell it and buy the right frame" sort of deals?
Answers in order:

Easy to do - hammer or clamp on a shaped block of wood. If done poorly, yes. I'm sure it's been lots of times DIY. Some people actually value having the right frame, others not so much.
 
Here's a couple of links to conversations about the process, with photos of the tools used. Some of the experience is coming from frame builders and some from hobbiests, so a fair pool of information. It seems pretty straight forward, depending on ones ability with the use of hand tools.

You should be able to get a clear idea on how it's done and an idea to make a tool with what you have available to you. If you search around those discussion forums you should be able to find more info.

I think that the heat that has been mentioned is not needed, and may be a bad idea.

https://groups.google.com/forum/#!search/dimple$20chainstay/framebuilders/IyZJkCQRLDE/YcXgSeHXFAAJ

https://groups.google.com/forum/#!search/dimple$20chainstay/650b/z6jRzSNIr5k/62CjPu29MHYJ
 
Discussion starter · #8 ·
Thanks for the feedback. I do worry about damage and potential early frame failure, especially at that part of the frame. That's the only place where I've cracked a steel frame (several years after damage that was similar to what adding clearance would do).

The DIY option looks doable, but it feels a bit half-assed. I assume that I'd then need to get the frame alignment checked as well.

I may just sell it and buy the right frame.

Also, I have no idea why this has the exclamation icon next to the title.
 
I may just sell it and buy the right frame.
If you like everything else about the frame, asking for quotes from frame builders seems like a reasonable thing to do before making that call.

I would say given the cost of alignments and tube replacement (sample prices: Bilenky Cycle Works ) it shouldn't be very expensive at all. Likely less than you would lose on selling the frame used, even getting a good price on it.

Worth a few e-mails and phone calls, again, if the frame is good for you in every other way.
 
Discussion starter · #11 ·
If you like everything else about the frame, asking for quotes from frame builders seems like a reasonable thing to do before making that call.

I would say given the cost of alignments and tube replacement (sample prices: Bilenky Cycle Works ) it shouldn't be very expensive at all. Likely less than you would lose on selling the frame used, even getting a good price on it.

Worth a few e-mails and phone calls, again, if the frame is good for you in every other way.
I like most things about the frame, but I'm not sure it's worth spending probably a couple hundred bucks + shipping to modify it. Thanks for the Bilenky link - I forgot about them. I'll see what the actual cost is and go from there.

I wouldn't do it on heat treated or air hardening steel - 725, 753, 853, Ox, etc. Like trying to bend a knife blade.
The main tubes are 520, so I don't think that's a worry.
 
I may just sell it and buy the right frame.
That is what I would do. No sense trying to fit a round peg into a square hole. Get the right frame for the job, IMHO.
 
I like most things about the frame, but I'm not sure it's worth spending probably a couple hundred bucks + shipping to modify it. Thanks for the Bilenky link - I forgot about them. I'll see what the actual cost is and go from there.



The main tubes are 520, so I don't think that's a worry.
A possible option, depending on the details of the frame and components...is doing a 650B conversion.
 
A possible option, depending on the details of the frame and components...is doing a 650B conversion.
Hmmm. I like this idea! 650b wheels and tires will give you more room to run wider tires. I would try this before deciding to change horses.

Keep in mind that a 30x700c is around the same diameter as a 47x650b.
 
Discussion starter · #16 ·
Hmmm. I like this idea! 650b wheels and tires will give you more room to run wider tires. I would try this before deciding to change horses.

Keep in mind that a 30x700c is around the same diameter as a 47x650b.
I have thought about that as well. Ultimately, what I'd like here is one bike to replace my road bike and my rough-road bike, so I'm not sure 650 is the way to go.

I got quotes from a couple of places to dimple and align. The cost isn't too bad. $100 for the steel frame, and just for the hell of it, I got a quote for turning my Lynksey Cooper road frame into a road+ frame. $150 to dimple, $350 to raise the brake bridge for medium-reach brakes. That'll only get a 30 though (takes a wide 28 now, limited by the caliper), so not really worth it.

Anyway, I'm leaning towards getting a Gunnar Sport and a 1x11 Force drivetrain. I'm a bit pissed that the frame I just bought wasn't quite what is was supposed to be, but **** happens, I guess.
 
Hmmm. I like this idea! 650b wheels and tires will give you more room to run wider tires. I would try this before deciding to change horses.

Keep in mind that a 30x700c is around the same diameter as a 47x650b.
This is the thing, as much as I'm a 650b guy, if the 30mm 700c tire doesn't fit between the stays I don't see a 650b\47 fitting. And even a 38mm 650b will probably be hard pressed to fit in there without altering the stays.

I think altering the stays is a workable solution, on an older used bike, but on a new bike I don't know that I'd want to change things.
 
I have thought about that as well. Ultimately, what I'd like here is one bike to replace my road bike and my rough-road bike, so I'm not sure 650 is the way to go.

I got quotes from a couple of places to dimple and align. The cost isn't too bad. $100 for the steel frame, and just for the hell of it, I got a quote for turning my Lynksey Cooper road frame into a road+ frame. $150 to dimple, $350 to raise the brake bridge for medium-reach brakes. That'll only get a 30 though (takes a wide 28 now, limited by the caliper), so not really worth it.

Anyway, I'm leaning towards getting a Gunnar Sport and a 1x11 Force drivetrain. I'm a bit pissed that the frame I just bought wasn't quite what is was supposed to be, but **** happens, I guess.
That $100 to dimple the stays may be worth it. Did you ask if the paint will hold up at the dimple, or flake off from the movement?

Have you talked to the manufacturer to see what they have to say about the bike not meeting ability of taking the claimed tire size?
 
I have thought about that as well. Ultimately, what I'd like here is one bike to replace my road bike and my rough-road bike, so I'm not sure 650 is the way to go.

I got quotes from a couple of places to dimple and align. The cost isn't too bad. $100 for the steel frame, and just for the hell of it, I got a quote for turning my Lynksey Cooper road frame into a road+ frame. $150 to dimple, $350 to raise the brake bridge for medium-reach brakes. That'll only get a 30 though (takes a wide 28 now, limited by the caliper), so not really worth it.

Anyway, I'm leaning towards getting a Gunnar Sport and a 1x11 Force drivetrain. I'm a bit pissed that the frame I just bought wasn't quite what is was supposed to be, but **** happens, I guess.

Well it sort of was, from what you've said.

Tires vary in width in the same size class...and the plethora of rim widths cause more variations in sizing. I read "maximum clearance" statements on frames as "LOL hope you don't have any sand or gravel stuck to your tire"....unless there are reviews with specific tire/wheel combo examples showing comfortable clearance. Particularly on rim-brake frame/forks The difference even then between a 34mm tire and a 31.9mm tire is only a mm per side--which is within tolerance of the tire alone.

If you throw in the towel on making this frame work for what you want--at least these days there's no shortage of stock models...not shortages of frame/forks you can build up to get exactly what you want. Course, depends on your budget and wants and time frame.
 
This is the thing, as much as I'm a 650b guy, if the 30mm 700c tire doesn't fit between the stays I don't see a 650b\47 fitting. And even a 38mm 650b will probably be hard pressed to fit in there without altering the stays.

I think altering the stays is a workable solution, on an older used bike, but on a new bike I don't know that I'd want to change things.
Understood. I was just mentioning the similar diameters. A 38x650b would probably fit even though there are no guarantees it will. Best thing would be if the OP has a way of testing out someone else's wheel and tire (bike shop??) to see if it will work.
 
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