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Old 05-09-06, 09:02 PM   #1
NDG
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Fiting a new wheel with larger axle on a older Miyata? Help.

Recently had to replace the rear wheel on my early eighties Miyata six ten.
My local bike shop sold me a new 27" alloy wheel. When I got home, I realized that I could not get the wheel to fit on my bike because the new axle was too wide by something like 7-10 milimeters. Went back to the shop and they told me "No problem, we just need to pull apart the chainstays.", which they then proceeded to do (with some effort).
The wheel is now on the bike and it appears to work fine. However, I notice that the rear derailleur is a bit more noisy than usual.
Just wondering if this could be caused by the fact that pulling apart the chainstays that much ended up imposing an excessive angle on the rear derailleur in comparison to the front chainrings. I now have the impression that they are not perfectly lined up.
So did the bike shop do the right thing or should they have taken apart the axle on the new wheel and replaced it with a shorter one?
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Old 05-10-06, 04:58 AM   #2
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Ask the shop to check your dropout alignment.

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Old 05-10-06, 11:30 AM   #3
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Thanks. But the question remains, would it have normally been better to just change the axle?

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Ask the shop to check your dropout alignment.

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Old 05-10-06, 11:44 AM   #4
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Yes, but it could be that they don't have a proper replacement. Does this happen in all the gears, or in just some? Is your shifting indexed, or friction? The answers to these questions will help point to the answer.
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Old 05-10-06, 03:11 PM   #5
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It pretty much happens on all the gears. Its not a majot noise, but definitely more than usual.
Friction shifting.

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Yes, but it could be that they don't have a proper replacement. Does this happen in all the gears, or in just some? Is your shifting indexed, or friction? The answers to these questions will help point to the answer.
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Old 05-10-06, 03:28 PM   #6
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Hey NDG, what you describe sounds like they just pulled the dropouts apart by brute force and slid the rear wheel in. If the difference is as extreme as you say it is they should properly "cold set" the dropouts and then realign them. If you are using the same freewheel as before I would suggest usuing your old axel and having them redish the rear wheel to fit properly, they can simply cut down the new axel and respace as well. If you are using a modern hub with a cassette though you may have to have the dropouts properly spread, see: http://www.sheldonbrown.com/frame-spacing.html
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Old 05-10-06, 06:16 PM   #7
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My six ten was 126mm, but the stays are flexible enough to take a 130mm hub, in my case a Tiagra. It didn't need any mods and the new 10 speed cassette aligns perfectly with my original Sugino TGT crankset.

Your setup should be just as good. Could your new wheel be 135mm? That would be a major problem.

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Old 05-10-06, 06:49 PM   #8
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I now understand that I really need to go and measure the width of my axle. I'm off to go and do that right now. Will be back soon with the info.

Quote:
Originally Posted by miyata610
My six ten was 126mm, but the stays are flexible enough to take a 130mm hub, in my case a Tiagra. It didn't need any mods and the new 10 speed cassette aligns perfectly with my original Sugino TGT crankset.

Your setup should be just as good. Could your new wheel be 135mm? That would be a major problem.

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Old 05-10-06, 07:27 PM   #9
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Just checked. The spacing between the two dropouts is approximately 127 mm.
The axle length seems to be about 135 mm (although I have no specific tool to measure this, so my measurement is certainly not precise). When I remove the wheel, the dropouts spring back to their original position. To put it back in, I have to pull apart the dropouts. It requires some significant force, but I can do it without too much problem.

So if I understand correctly, I have four choices:
(1) Leave everything as is. The additional noise is not that bothersome.
(2) Have the shop replace the axle on the new wheel they sold me (although they probably will charge, saying that the wheel fits as is... bla bla bla).
(3) I could also just get a new axle and install it myself (although that would require a little extra work on my part).
(4) "Cold set" the frame with a 2 by 4 piece of wood, as suggested by cyclotoine and as described on Sheldon Brown's site. Sounds fun.

Not quite sure yet what I will do.
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Old 05-10-06, 08:38 PM   #10
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If the new hub is 135mm then I would take it back and get one that's 130mm.

130mm is the norm for all modern road bikes with all the current cassettes from 8 speed to 10 speed.

135mm is used principally on mountain bikes, but is also used on hybrids.

For what you are doing 130mm is the correct choice and it requires very little stretch on you existing frame. It's also likely to align better me thinks (I'm guessing).

Your LBS has done the wrong thing selling you a 135mm wheel, they should exchange it without complaint.

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Old 05-10-06, 09:15 PM   #11
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Quote:
Originally Posted by NDG
Just checked. The spacing between the two dropouts is approximately 127 mm.
The axle length seems to be about 135 mm (although I have no specific tool to measure this, so my measurement is certainly not precise). When I remove the wheel, the dropouts spring back to their original position. To put it back in, I have to pull apart the dropouts. It requires some significant force, but I can do it without too much problem.

So if I understand correctly, I have four choices:
(1) Leave everything as is. The additional noise is not that bothersome.
(2) Have the shop replace the axle on the new wheel they sold me (although they probably will charge, saying that the wheel fits as is... bla bla bla).
(3) I could also just get a new axle and install it myself (although that would require a little extra work on my part).
(4) "Cold set" the frame with a 2 by 4 piece of wood, as suggested by cyclotoine and as described on Sheldon Brown's site. Sounds fun.
The noise has no relation to the frame spacing, it is something else.

If the 135 axle works, leave it be, it makes for a stronger wheel that way. If you shortnen it to 130, it all comes off the left side, and the wheel will need to be re-dished, which will weaken it. Since this is a touring bike, you're better off with the 135 hub.

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Old 05-10-06, 09:25 PM   #12
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So are you guys saying that it's possible to fit a 130 mm hub into a 126 mm rear axle simply by pulling hard on the rear triangles? I'm in the same situation, and choices for wheels with 126 mm hubs seem really quite limited.
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Old 05-11-06, 11:32 AM   #13
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Yes 130mm should be no problem in a 126mm. Sheldon's word is kind of the final "truth". However if you are on tour it is a hell of a lot easier if you don't have a wheel wedged in there when you need to change a flat. I agree with Miyata 610, your LBS should not have sold you a 135mm spaced hub in the first place. I think you are entiled to demand they replace the wheel with a 130 at their expense (since the wheel is not used).
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Old 05-11-06, 02:44 PM   #14
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I'm thinking the increase in noise is due to the spread dropouts and derailleur hanger no longer being exactly parallel to each other and the centreline of the frame. Also, the chain line has moved a tiny bit outboard, but that should improve it in the lower gears, so it's got to be the former. Tweaking the derailleur hanger back into parallel should fix it. However, if you have to forcibly spread the dropouts to get the wheel in, the rear triangle hasn't been cold set enough.
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Old 05-11-06, 03:32 PM   #15
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All right. Thanks Sheldon for the input. But I would have liked to hear from you why you think that having the dropouts spread farther out could not in principle perturb the alignment of the rear derailleur with the freewheel cogs. By the way, I have indeed not yet cold set the frame.

In any case, I now understand that if I go back to my LBS, I have to ask for them to replace the whole wheel, not just change the axle.
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Old 05-11-06, 05:02 PM   #16
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Quote:
Originally Posted by NDG
All right. Thanks Sheldon for the input. But I would have liked to hear from you why you think that having the dropouts spread farther out could not in principle perturb the alignment of the rear derailleur with the freewheel cogs.
'Cause I did the math. If you had read my Frame Spacing article, you'd know that a 6 mm change in spacing only changes the dropout alignment by 1/2 degree or less.

Quote:
Originally Posted by NDG
By the way, I have indeed not yet cold set the frame. In any case, I now understand that if I go back to my LBS, I have to ask for them to replace the whole wheel, not just change the axle.
My advice is to keep the wheel, and cold set the frame if it bothers you. Most serious touring frames these days are designed to work with 135 mm hubs, because it makes for a stronger wheel.

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Old 05-11-06, 05:44 PM   #17
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Quote:
Originally Posted by Sheldon Brown
My advice is to keep the wheel, and cold set the frame if it bothers you. Most serious touring frames these days are designed to work with 135 mm hubs, because it makes for a stronger wheel.
Well, true that the wheel would be stronger, but what if he doesn't need such strength? If he's not going to go touring with 100 pounds in his bags, wouldn't it be easier to go for a pair of 130mm's and not have to stretch the frame out so far? Just my idea.
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Old 05-11-06, 05:58 PM   #18
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Quote:
Originally Posted by the beef
Well, true that the wheel would be stronger, but what if he doesn't need such strength? If he's not going to go touring with 100 pounds in his bags, wouldn't it be easier to go for a pair of 130mm's and not have to stretch the frame out so far? Just my idea.
Easier to replace the wheel than to spread the frame? I don't think so. Spreading a nice steel frame like this is pretty trivial.

What advantage would he gain by going to the weaker wheel?

If the downgraded wheel were to start breaking spokes in the future, how dumb whold he feel?

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Old 05-11-06, 06:10 PM   #19
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Quote:
Originally Posted by Sheldon Brown
'Cause I did the math. If you had read my Frame Spacing article, you'd know that a 6 mm change in spacing only changes the dropout alignment by 1/2 degree or less.
Yes but he is going from what should be 126mm (me measured 127 probably because of the shop guys forcing the wheel in) to 135mm so almost a cm. Couldn't that throw off the alignment enough? In addition I read that if you spread a frame without realigning the drop-outs you can break axels, does this have any truth? and if yes then why/how? I still feel uneasy about spreading the dropouts that much as they are spreading at the bridges and I would fear cracking there especially if he has it spread to 135mm and then does some heavily loaded touring. So I see... 1. get a 130mm hub and have piece of mind and it is going to be strong enough anyway or 2. start spreading and permanently displace the frame putting added stress on the bridges... personally I would go with option 1. just my 2cents.
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Old 05-11-06, 06:57 PM   #20
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If I understand correctly the explanations regarding cold setting frames on Sheldon's site, this is actually a modification that is not irreversible. So I would not risk much doing that. I guess I'll have to get myself a 2 by 4 this weekend and give it a shot, hopefully spreading both sides equally...

Thanks for everybody's advices.
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Old 05-12-06, 01:21 PM   #21
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I am running a 135 axle on my 83 Trek with no problems at all. I am using a 8 speed with a spacer and a 7 speed cassette. I did not cold set the chain stays I just pull them apart when replacing the wheel, not a big deal.
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Old 05-12-06, 02:53 PM   #22
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I don't understand what you mean by a spacer. Where exactly is that spacer localized?

Quote:
Originally Posted by a77impala
I am running a 135 axle on my 83 Trek with no problems at all. I am using a 8 speed with a spacer and a 7 speed cassette. I did not cold set the chain stays I just pull them apart when replacing the wheel, not a big deal.
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Old 05-12-06, 05:14 PM   #23
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I'd also like to know about the spacer. I've currently got a 130mm wheel with an standard-range 8-speed wedged into my old Schwinn with 126mm spacing. However, today I found that I couldn't get into the two biggest cogs in the back, no matter how hard I tried or what chainring I was in on the front. Does this have anything to do with needing a spacer, or is it soemthing else entirely?

Really frustrating. Hope this is relevant to the thread.
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Old 05-12-06, 05:27 PM   #24
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Quote:
Originally Posted by a77impala
I am running a 135 axle on my 83 Trek with no problems at all. I am using a 8 speed with a spacer and a 7 speed cassette.

Quote:
Originally Posted by NDG
I don't understand what you mean by a spacer. Where exactly is that spacer localized?
Quote:
Originally Posted by the beef
I'd also like to know about the spacer. I've currently got a 130mm wheel with an standard-range 8-speed wedged into my old Schwinn with 126mm spacing.
The spacer a77impala was talking about has nothing to do with NDG or the beef's situation.

a77impala is running a 7-speed cassette on an 8-speed hub, so he or she needs a 4.5 mm spacer to make up for the missing sprocket, otherwise the 7-speed cassette would flop around on the wider Freehub body.

Quote:
Originally Posted by the beef
However, today I found that I couldn't get into the two biggest cogs in the back, no matter how hard I tried or what chainring I was in on the front. Does this have anything to do with needing a spacer, or is it soemthing else entirely?
Something else entirely.

Most likely either the derailer's low gear limit stop has been overtightened, or the shift cable has too much slack in it.

See: http://sheldonbrown.com/derailer-adjustment

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Old 05-12-06, 05:48 PM   #25
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Quote:
Originally Posted by Sheldon Brown
The spacer a77impala was talking about has nothing to do with NDG or the beef's situation.

a77impala is running a 7-speed cassette on an 8-speed hub, so he or she needs a 4.5 mm spacer to make up for the missing sprocket, otherwise the 7-speed cassette would flop around on the wider Freehub body.



Something else entirely.

Most likely either the derailer's low gear limit stop has been overtightened, or the shift cable has too much slack in it.

See: http://sheldonbrown.com/derailer-adjustment

Sheldon "Unnecessary Information Can Lead To Confusion" Brown
Ah, thanks a lot for that piece of information, Sheldon. You're always a great help.
I kept loosening the limit screw until it would engage the rear ring, it took probably twenty full turns counter-clockwise. Now the screw's sticking out a very good amount, but hey, everything works fine, and it doesn't shift into the spokes. Props.

Sorry about the small (unintentional) thread hijack.

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