# Standard F/R Hub Size



## rideronthestorm (Mar 4, 2006)

Does anyone know what's the standard front and rear hub size on mtb bikes? Are there any known forks or frames that have a size that is larger then standard? 

Thanks.


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## KingCrimson (Jun 26, 2008)

110/135mm


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## Boulder Pilot (Jan 23, 2004)

rideronthestorm said:


> Does anyone know what's the standard front and rear hub size on mtb bikes? Are there any known forks or frames that have a size that is larger then standard?


I'm not sure what you are asking. Standard front quick release is 9mm. Rear hub standard width is 135mm. RockShox has Maxle, there are also 20mm fork and hubs. Before I go on and confuse the both of us, what is it specifically that you are trying to find out?


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## emtnate (Feb 9, 2008)

As has been said standard spacing between the dropouts is 110mm front / 135 mm rear. Like Boulder Pilot said there is some different diameters of axles out there.

Surly Pugsley's uses 135mm between the dropouts of the front and rear in order to hold up to 4" wide tires.


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## rideronthestorm (Mar 4, 2006)

*hub width size*



Boulder Pilot said:


> I'm not sure what you are asking. Standard front quick release is 9mm. Rear hub standard width is 135mm. RockShox has Maxle, there are also 20mm fork and hubs. Before I go on and confuse the both of us, what is it specifically that you are trying to find out?


Hi, i was just trying to get the std. width size of mtb bikes. Seems like KingCrimson provided me with the info. Thanks!


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## seawind161 (May 1, 2008)

Is this a typo or do I have abnormal forks? 

I just measured two forks (Fox F100, Marz MX Pro Lo) and both were 100mm, not 110. Or are you guys talking about maybe DH gear that I don't know anything about? :???:


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## KingCrimson (Jun 26, 2008)

You measured wrong.


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## seawind161 (May 1, 2008)

KingCrimson said:


> You measured wrong.


No, I didn't.

100 mm Modern front hubs. 
110 mm Rear older track, coaster brake and other single-speed hubs. *Also, front hubs for Downhill bikes with 20 mm axles. *

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


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## tech_dog (Aug 25, 2008)

Never mind...


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## KingCrimson (Jun 26, 2008)

Good move quoting Sheldon without reading the article. That's where 90% of MTBR's "experts" come from.

"Overall axle length for quick release hubs is commonly 11 mm longer than the over-lock-nut distance listed, 5.5 mm on each side."


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## seawind161 (May 1, 2008)

KingCrimson said:


> Good move quoting Sheldon without reading the article. That's where 90% of MTBR's "experts" come from.
> 
> "Overall axle length for quick release hubs is commonly 11 mm longer than the over-lock-nut distance listed, 5.5 mm on each side."


Might want to work on that reading comprehension. I believe the OP asked for hub size, not axle length.

You want to try cramming a 110mm hub into a standard XC fork, be my guest. You're the expert. I recommend a 12-lb hammer. :thumbsup:

(BTW, 100mm hub plus 11mm exposed axle would be 111mm, not 110)


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## KingCrimson (Jun 26, 2008)

How exact is the fit of a hub in a fork? Is it a precision process?

How big is a mm?


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## seawind161 (May 1, 2008)

KingCrimson said:


> How exact is the fit of a hub in a fork? Is it a precision process?
> 
> How big is a mm?


It's a question of terminology. Hub size is measured locknut-to-locknut. Sheldon's site says that axle length can vary from 5.5mm per side down to 1 or 2 mm, so you obviously can't spec a dropout width based on that measurement, so locknut-to-locknut it is.

Standard 8/9 speed rear dropouts are spaced 135mm from inside face to inside face. The hub that fits into them will be 135mm locknut-to-locknut. The axle may well be 145mm, but it's still a 135mm hub.

How exact is the fit of a hub in a fork? Well, the two I measured a short while ago measured 101 and 102mm. A little slack allows easy mounting of the wheel, and the QR skewer easily compresses the fork to secure the wheel.

How big is a mm? Takes 25.4 of 'em to make an inch. Just a little more than a RCH. 

If you go to this link:
http://www.bikeman.com/QR2200.html
to order skewers, you'll see that you get one 100mm, and one 135mm. Standard.

110mm belongs to the DH guys with 20mm axles, and I don't know the first damn thing about those. :skep:


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## Boulder Pilot (Jan 23, 2004)

Standard quick release front hubs = 100mm nut to nut
20mm thru axle front hubs = 110mm
Standard rear hubs = 135mm
12mm rear hubs = 150mm-165mm


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## tech_dog (Aug 25, 2008)

KingCrimson said:


> How exact is the fit of a hub in a fork? Is it a precision process?
> 
> How big is a mm?


I've never had one that wasn't exact.

There are 25.4mm in an inch.


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## KingCrimson (Jun 26, 2008)

Seawind, it was apples to oranges. 

Sorry about that. :thumbsup:


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## seawind161 (May 1, 2008)

KingCrimson said:


> Seawind, it was apples to oranges.
> 
> Sorry about that. :thumbsup:


No probs. Sorry if I sounded like an a-hole. Bad day, no ride.:thumbsup:


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