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The specifics:

Have an older Litespeed Vortex (2005) frame. I think back in these days the super skinny 20mm tires were in vogue. Anyways it seems like the frame might be super optimized towards these skinnier sizes? I put 25mm tires on and now when I'm out of the saddle on the downstroke I can hear an ever so faint rub for a second.

How dangerous is this situation - can I try tightening the quick release on the back wheel down super tight - or possibly something else?

Thanks :D

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    Despite what Paparazzi says, the first thing to check is that the wheel is properly centered -- it's quite often the case that one side of the axle is further into the dropouts than the other side, or out of kilter for some other reason. – Daniel R Hicks Apr 13 '17 at 2:05
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    A hack one could do, on a tire with heavy lugs, is to somehow cut/grind down the corners of the lugs. On many tires you could narrow the outside corner by 1/4 inch or so without affecting the integrity of the tire and only a tiny effect on traction. – Daniel R Hicks Apr 13 '17 at 2:07
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    @DanielRHicks Slip and not centered are not the same thing. If you consider the context of my answer I specifically ask if it is rubbing on both sides. Narrow the outside corner by 1/4 inch? What bicycle tire even has 1/4 inch of rubber? – paparazzo Apr 13 '17 at 2:48
  • @Paparazzi - I've seen a lot of mountain bike tires that could lose a quarter inch on the corners and not miss it. – Daniel R Hicks Apr 13 '17 at 11:49
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    this sounds like wheel or frame flex in a tight clearance tire/frame combination. – Paul Apr 13 '17 at 14:41
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Assuming the wheel is good (is fully seated and centered properly in the dropouts and is true; if you spin it along its axis, there shouldn't be lateral movement) you shouldn't be running a tire that rubs on the frame. This can eat out the paint of the frame, the frame, and/or the tire.

Try moving to a different tire (possibly a smaller one, like a 700x23) if the wheel is good. Remember that you need some space between the tire and the frame, since the bicycle flexes under load (damaged frames can flex more than the undamaged frame, so might be something to check up on).

  • yeah I think its a matter of having to go to a skinnier tire width. Wheel is brand new, frame seems like its true and in very good condition, but the clearance for the 25mm is so incredibly tiny. Right now the tire tits actually rub against the chainstay when spinning the wheel, it hits the tire tit like halfway so I imagine < 1mm of clearance! – maxwell Apr 12 '17 at 22:18
  • could you advise on optimal distance re: tire to chainstay? – maxwell Apr 12 '17 at 22:20
  • It depends on how much the frame flexes, but I'd hope for a few mm. On the low end, maybe 3-5 mm. It looks like the bike was originally sold with 23 mm slicks, so I'd go with that size or smaller. Also, note that not all tires of the same marked size have the same outer diameter. So its conceivable some other 25 mm tire may fit better. – Batman Apr 12 '17 at 22:28
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    The wheel being brand new doesn't matter. If a wheel is perfectly dished and would give 2 mm of clearance on a perfect bike, a frame only has to be 1mm off (not much) to reduce the clearance to almost nothing on one side. Wheels can be dished perfectly when built, but they should also be dished to the frame they are for when you deal with small clearances. – Deleted User Apr 13 '17 at 17:57
  • Brand new wheels are rarely perfect too, especially on lower end ones. – Batman Apr 13 '17 at 18:57
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I seriously doubt the axle is slipping in the frame. So a tighter quick release will not help.

The frame will flex a bit under load. That is natural.

I assume you have checked the wheel is true?

I would not rub on an expensive frame. I would not rub on even a cheap frame.

Look for a thinner tire. Not all 25 are the same. Limited but there are some 24. Or drop down to 23 like batman said (+1). If you try other 25 mm the good news it you can still use it as a spare front but you already have one spare front. Something like a Continental Grand Prix Force 24 mm?

Can you tell if it is rubbing on both sides? You could mount a camera.

  • " Not all 25 are the same. " Yah! I have Michelin Endurance 25mm and it feels like they are really big? Do you have any more knowledge about which brands run big? I want to run 25's on this bike so I am kinda bummed about having to drop down.. – maxwell Apr 12 '17 at 22:34
  • @maxwell No I don't know which brands run big or small. I notice that heavy duty tend to have a more upright (not perfectly round) profile. I think that is semi endurance type tire now. – paparazzo Apr 12 '17 at 22:40
  • Not sure there is a difference in a 24 and 25 that runs small. – paparazzo Apr 12 '17 at 22:50
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I build my own rear road wheel and had a terrible time making it dished correctly. Instead the rim ended up too far left and rubbed on the frame.

Could be that your rear wheel is not dished enough?

If you measure the distance between the rim edge and the chainstay on both sides, it should be identical. Anything more than 5% difference would be time for a redish. Your LBS would be better at this than messing about with a spoke spanner - mine only cost $25NZ for a redish and true.

  • Do you have access to a dishing tool or a truing stand? Setting the dish should be a relatively straightforward task if you have access to either – Rider_X Apr 13 '17 at 13:35
  • My truing stand is an old front fork mounted in a bench vise. Not exactly quality. I used a cardboard cutout to measure dish but it just looked wrong. I never realised how far "over" a rear wheel is, and that was only a 7 speed. 8-11 speeds would be even further towards "flat" on the drive side. – Criggie Apr 13 '17 at 22:10
  • Yes this is why you build a rear wheel with shorter spokes on the drive side. Try fixing your dish measuring device to one side of the stand and flip the wheel to set the dish. Should be easier to center the rim to the hub this way. Dish tools essentially do this. – Rider_X Apr 13 '17 at 22:13
  • @Rider_X Yes that was all done using several spoke calculators who all agreed within .5 mm, for both sides. OP should check his dishing and see if that's contributing to chainstay rub on one side. – Criggie Apr 14 '17 at 0:29

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