mander

For a while now I've bemoaned the fact that it's hard to get an inexpensive fixed hub that's truly suitable for hardcore, high mileage, all weather commuting. I'e wished that Shimano would make an XT fixed hub with those external rubber boots, those nice hard bearing races and so on. Today I realized, duh, people just convert 6 bolt disc hubs into fixed hubs. So I am wondering how good of an idea this would be. I can get the 6 bolt HF version of the XT front hub (that's the m756, tech doc is here) for cheap over here, but I would need to replace the axle with a longer (probably solid) one, space it out to 130 or so and get one of those cogs that's been cut to go onto a 6bolt disc mount. Then I'd be running a wheel with small, front hub style bearings instead of those big ~1/4" bearings you get in Shimano rear wheels... or is it possible/ advisable to cram in the big bearings??

So... would the resulting wheel be worth the PITA factor * financial cost, or should i stop thinking so much and just get a formula hub?

The LT

PM lofarkas I don't know if he posts here much any more but I remember him having a front disc hub converted for rear fixed use.

I am running a fixed MTB with one of the tomicogs and it has been great so far. But I am just using a rear disc MTB hub flipped around so no respacing or anything like that

mander

Thanks jb, the tomicogs are what I was planning to use. Through google I found lofarkas' writeup: https://www.bikeforums.net/singlespeed-fixed-gear/232041-disc-front-hub-bolt-cog-report.html

Edit: That's some interestin reading! I think I might go for this.

LóFarkas

Yeah, I'm here. I guess everything is in the other thread but feel free to harass me with any questions.
It's been running fine since then, although I ashamedly admit that I don't ride all that much these days.

Solid axle and respace to 130 is exactly what I did and it is pretty straightforward if you know a bit about these things. Get M10 axle (e.g. shimano MTB axle), spacers, cone wrenches, 2 extra locknuts, a pair of axle nuts and get wrenchin'.

Of course, if you're very heavy and bash into things a lot then you may be better off with something that has bigger bearings spaced further apart, and less protruding axle to bend. I'm pretty sure it's solid enough for riding on paved roads if you actually hop the curbs and don't just run into them etc.

Aeroplane

Wheels manufacturing makes a great heat-treated solid axle to replace the QR axle for Shimano hubs. Just get a solid axle that is long enough, put it together, respace (easy), and go about your business.

ksyrius

Have you looked at surly they make a mtb spaced rear hub that is fix/free, in 135mm or 130mm. I currently ride 120mm spaced surly rear and ive been rallying it hard and ive had no problems.

Cyclist0383

You can pick up a Miche rear hub for under 50 euro delivered. When the seals on the bearings give out replace them with Phil Wood ones and you'll be good for quite a while. I suspect that the Shimano setup will cost more than 50 euro all told, and the seals really won't be much better than the Miche.

mihlbach

I built a 6-bolt disk fixed wheel with a surly front disk hub for my SSMTB. The Surly front disk hub is a good candidate for a disk fixed hub conversion, because the front and rear bearings are the same size. All you need to do is swap the axle, cones, locknut, axle (track) nuts, and add some spacers. Here's a set of conversion instructions...https://www.fixedgeargallery.com/arti...mson/surlyhub/
If you dish the wheel symmetrically, you'll end up with about a 45mm chainline...if that bothers you, there are many ways to tweak your chainline to get it perfect (bb spacer, shorter BB spindle, slightly dish the wheel, etc.).

I am fairly certain that any of the 135mm spaced rear disk hubs would give you a much wider chainline.

MIN 

I have an old XT disc hub I am not using. Is there a way to convert it down to 120mm OLD?

The LT

The 135mm spaced hubs give you something on the order of a 52mm chainline which is the outer most position on a standard MTB triple crankset

mihlbach

mander

That's real handy to know mihlbach, thanks. 45 mm chainline is A OK for me. I could throw a ring on the outer position of the 105 octalink cranks on my crosscheck, and i'd be in business. I need to figure out where things would be at for the xt hub, this sounds like a job for the Pythagorean Theorem.

riderx

Personally I'd just use a rear hub. Disc MTB or a proper fixed. If you are looking for a non-mtb chainline use the Surly 120mm track hub and pop two 5mm spacers on it, I've done it on a Crosscheck before. Cheaper than an axle swap.

The only reason I would use a front disc is if you have a built wheel sitting around unused. If you are building from scratch, use a rear hub. Just my $.02

mihlbach

Hard to fit a 135mm spaced mtb ss hub into a 120mm spaced frame and expect to get satisfactory results. My aluminum Redline monocog is 110mm..theres no way I could fit a 135mm hub in there.
A disk hub eliminates the possibility of stripping the threads, which is a serious concern if you are riding low gear ratios, like on singletrack.

riderx

OP said he's using it on a crosscheck which is a 132.5mm spacing. I wouldn't be telling him to spread a 120 frame, heck he could just you the 120 Surly (unmodified) I recommended above if that were the case. If you've got a 110mm frame, the front hub is a viable option. I've got multiple MTB fixed setups that run suicide, standard fixed and tomicog setups and have not stripped any hubs. Not saying it doesn't happen, but it's not the boogy man some make it out to be. The only threaded hub I've stripped was a cheap proper fixed gear set up with a street gear and I attribute that to the quality of the hub and cog.

mihlbach

Yeah, I agree for the most part...whatever works works. Ultimately all that matters is finding a mix of parts that will (1) fit in your frame, and (2) will give you at least a half-assed chainline.

wroomwroomoops

Wait a sec. You have an aluminum frame that has 110mm spacing in the rear? That seems so odd.

By the way, I have a Redline Monocog, too. It's however a steel frame (a 29er) and is spaced 135mm. Did Redline make a different Monocog earlier? What kind of frame is that anyway, with 110mm spacing in the rear?

yonderboy

The 26" Monocogs used to be 110mm for BMX hubs. Only when they started offering a 29er version (I think 05 or 06) did they switch to the 135mm spacing.

You can still find them if you search for Monocog Flight Alloy.

mihlbach

Correct....mine's a 2004, which I think is the last year for the 110mm spaced frames. After that they went with 135mm.

wroomwroomoops

Holy moly, that's interesting. I know Redline makes this Monocog Flite (or flight?) 29er, which is aluminum if I recall correctly. Does that have 110mm spacing?