# Narrowing a multi-speed hub for 110mm frame?



## BATRG3 (Dec 11, 2012)

I'm aware of 3spd BMX cassettes, which I understand to be rare and expensive. Also a very limited selection of IGH.

But I'm asking the question of whether we can feasibly shorten an existing hub to 110mm for use with a 5 speed freewheel?

I'm looking at a 6 speed hub with 126mm OLD.
Wheel Master Alloy Rear Hub, 6 Speed FW, B/O, 32h, Silver

Can we not buy 5.5mm by using a 5spd freewheel instead, and shortening the spacer accordingly?

Then on the opposite side, I see the cone and locknut taking up a bit of room. Would it be unreasonable to try to take about as much material away between the two of them?

With 115mm left, I would think the frame could easily stretch for the remaining 5mm. If it was even, the dishing would be the same, but if not, I don't see a concern with more dishing.

Surely if it was this easy someone would have done it already, right?


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## tkavan01 (Jun 1, 2004)

I looked into this with my son's spawn, the dish required to make the rear wheel line up was quite ridiculous. I even looked into cutting the hub and re-welding it, but it just didn't work out... The best bet seemed to be convert to disc brakes and take a spreader bar to the rear end, I wasn't willing to risk my sons ride though, he like it too much.


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## GrayJay (May 16, 2011)

What is the frame this is going in? If a steel frame, just cold-set it wider.

If you do narrow a threaded hub axle, starting with a hub with narrow distance between the flanges will result is best dish, a hub with wide flange spacing will have very uneven spoke tension. One option for your project might be to instead use a 3-speed freewheel, about 10mm narrower than a 5-speed;

Bicycle Repair Parts Scooter 3 Speed Sprocket Threaded Freewheel | eBay


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## BATRG3 (Dec 11, 2012)

I didn't realize that was compatible with a standard freewheel, thought it was just for a scooter.


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## TigWorld (Feb 8, 2010)

Get yourself a BMX style hub that uses a splined cassette freehub. I did some mods to one that meant I could use a modified 5 speed XT cassette for a 1x5 setup on a 110mm spaced hub. Take a look here for a bunch of pictures and details.


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## BATRG3 (Dec 11, 2012)

Thanks, that sounds like another good option.

Not sure myself which is better between the BMX with modified cassette and the freewheel with modified axle and nuts. Seems the FW mod would be cheaper and have less to mess up, but have more uncertainty in the spacing and more dishing concerns. Meanwhile the BMX would require a custom mated cassette and hub, though potentially only a custom cassette, and higher overall cost.


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## griffter18 (Jul 3, 2009)

Have a look at the thread http://forums.mtbr.com/families-riding-kids/hotrock-16-build-thank-you-850533.html
Read through to post 7 and you should get most of the info you need.


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## BATRG3 (Dec 11, 2012)

And here's another option, though a little expensive for my blood, especially since I'd still want to trim another 5mm or so.

Compass Bicycles: Hubs


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## mvwmvw (May 4, 2012)

The BMX Cassette hub, with proper spacers, would allow for three to five gears. Duh! This is great info. That and the little chain tug and one would be set to do anything.

Now I just have to find some junior cruiser wheels...


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## NYrr496 (Sep 10, 2008)

I narrowed an old 8 speed Shimano XT hub from 135 to 130 to put in a Gary Fisher Precaliber when my son was small. It worked perfectly. 
The splined BMX hub ideas sound perfect.


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## mvwmvw (May 4, 2012)

I just have to find a pair of cheap jr. cruiser wheels. I have a titanium Phase II mini bmx cruiser that was donated by the neighbor that would be perfect for my daughter as an ultralight first mountain bike. She is going on her third year racing bmx, so she'll be confident with the mid-school geometry I hope. I'm going to try and find a 1" threaded Mag 21 and maybe do a 26 front and 24 rear...


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