# How do you change the spacing on hubs?



## cloud8a (May 30, 2010)

I have a 125mm spacing on the rear dropouts of my bike. I have been looking for a rear wheel with a 130mm hub..but im having trouble finding exactly what i want. I came across a wheelset that has 120mm spacing, and it says it comes with two 5mm spacers so you can change the spacing from 120mm to 130mm. How exactly is that accomplished? Are the spacers compressing it? I'd like to fit the bike to a wheel without altering the frame, and someone recommended 130mm hubs. I guess my main question is, whats the difference between spacing 120mm hubs to 125mm vs 125 to 130mm hubs?


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## FBinNY (Jan 24, 2009)

I'm assuming that you're talking about a single speed or freewheel hub and not a cassette hub. 

If so spacers are usually added between the cone and locknut, to widen the width over the outside of the locknuts. With solid axles it's straightforward, but with QR axles which extend only 5mm beyond the locknuts adding anything more than a few millimeters requires a new longer axle.

Also the spacers need to be added with an eye to maintaining good chainline. Usually with single speed hubs you'd add equal amounts on both sides, but with multiple speed freewheels you'd add all the space to the left unless changing to a wider freewheel.

BTW- if this is a multi-gear cassette hub, life gets far more complicated and some or all of the above won't apply at all.


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## asad137 (Jul 29, 2009)

Is putting a 120mm hub in a 125mm spaced dropout such a terrible idea? Seems with only 2.5mm extra squeeze on each side, that should be easy enough for the frame to handle (I'm assuming it's a metal frame, not carbon).

Asad


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## FBinNY (Jan 24, 2009)

asad137 said:


> Is putting a 120mm hub in a 125mm spaced dropout such a terrible idea? Seems with only 2.5mm extra squeeze on each side, that should be easy enough for the frame to handle (I'm assuming it's a metal frame, not carbon).
> 
> Asad


It isn't that 5mm creates any mechanical issues, but it's so much easier to slip wheels into dropouts of the correct width. Having to flex dropouts open to clear the lock nuts, or press them closed to clear the QR unit is a minor nuisance, but certainly doable.


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## Kontact (Apr 1, 2011)

cloud8a said:


> I have a 125mm spacing on the rear dropouts of my bike. I have been looking for a rear wheel with a 130mm hub..but im having trouble finding exactly what i want. I came across a wheelset that has 120mm spacing, and it says it comes with two 5mm spacers so you can change the spacing from 120mm to 130mm. How exactly is that accomplished? Are the spacers compressing it? I'd like to fit the bike to a wheel without altering the frame, and someone recommended 130mm hubs. I guess my main question is, whats the difference between spacing 120mm hubs to 125mm vs 125 to 130mm hubs?


120s are single speed hubs with bolts, even after you put spacers on them. Do you want single speed hubs? If so, such a hub could also be respaced to 126 without issue.

I'd recommend telling us what kind of frame and hubs you're talking about so you can get accurate advise.

With some exceptions:
120mm - bolt on track/single speed standard
126mm - older quick release or bolt on multispeed standard (5 to 7 speed)
130mm - quick release multispeed road bike standard (8 to 11 speed)
135mm - quick release MTB/touring/disc standard (7 to 10 speed)


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## cloud8a (May 30, 2010)

Kontact said:


> 120s are single speed hubs with bolts, even after you put spacers on them. Do you want single speed hubs? If so, such a hub could also be respaced to 126 without issue.
> 
> I'd recommend telling us what kind of frame and hubs you're talking about so you can get accurate advise.
> 
> ...


Hello,

The frame is an old miyata, not sure what speed but it may have been a 7 speed. I am converting it to a single speed bike. I plan on putting a flip flop hub in the back, and have been advised to find one that is 130mm, and spacing it out. I assume that means putting spacers outside the rear dropouts, vs on the inside to widen the back if i was using a 120mm hub?

Thanks for any help, there isn't much information on how to do this type of thing out there, and my plan is to work on this bike myself..its my pet project.


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## Kontact (Apr 1, 2011)

cloud8a said:


> Hello,
> 
> The frame is an old miyata, not sure what speed but it may have been a 7 speed. I am converting it to a single speed bike. I plan on putting a flip flop hub in the back, and have been advised to find one that is 130mm, and spacing it out. I assume that means putting spacers outside the rear dropouts, vs on the inside to widen the back if i was using a 120mm hub?
> 
> Thanks for any help, there isn't much information on how to do this type of thing out there, and my plan is to work on this bike myself..its my pet project.


The "spacing" always refers to inside the dropouts.

Unless your frame isn't steel, just respace the dropouts to 120 instead of screwing with the wheel. This is a 10 minute job at a bike shop, and involves nothing more than squeezing each stay in 3mm, then making the dropouts parallel again. The frame can be reset to 126 or 130 later on without damage.

120 is the standard for single speed wheels, and you'll have an easier time with chainline on a flip flop if you leave it be. Plus you'll have more wheel choices.


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## cloud8a (May 30, 2010)

The rear dropouts are a bit wonky (unknown accident) so i don't think i will be squeezing it..Ive been advised to go for 130, which ive found out is hard to find a wheel for, though Ive found a few 120s with longer axles..would that mean i don't have to squeeze anything? Ive found quite a few 120s that say they can easily be spaced to accommodate it.



Kontact said:


> The "spacing" always refers to inside the dropouts.
> 
> Unless your frame isn't steel, just respace the dropouts to 120 instead of screwing with the wheel. This is a 10 minute job at a bike shop, and involves nothing more than squeezing each stay in 3mm, then making the dropouts parallel again. The frame can be reset to 126 or 130 later on without damage.
> 
> 120 is the standard for single speed wheels, and you'll have an easier time with chainline on a flip flop if you leave it be. Plus you'll have more wheel choices.


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## Kontact (Apr 1, 2011)

cloud8a said:


> The rear dropouts are a bit wonky (unknown accident) so i don't think i will be squeezing it..Ive been advised to go for 130, which ive found out is hard to find a wheel for, though Ive found a few 120s with longer axles..would that mean i don't have to squeeze anything? Ive found quite a few 120s that say they can easily be spaced to accommodate it.


I don't know why you were advised to go to 130, so I can't comment. I don't see any reason to do this, and am advising you differently. Putting a 130 wheel in 125 dropouts is going to cause just as much stress (if not more) than correctly setting them to 120. 

If the bike isn't safe, don't ride it. If it is safe and steel, the dropouts can be reset. It's that simple. If you walked into my shop, that's what I would tell you.


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## Scooper (Mar 4, 2007)

http://www.sheldonbrown.com/frame-spacing.html


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