Is it possible to convert a cassette hub to a fixed hub?
 

Is it possible to convert a cassette hub to a fixed hub? Surely, someone's opened up the pawl mechanisms and tried this. Anyone?

surly makes a hub adapter...http://www.surlybikes.com/parts.html
it's called "the fixxer".

Surly's Fixxer is the only bolt-on solution, but it is expensive. I think in the ballpark of $75. You could get a decentl entry-level hub for around $45 and have your wheel restrung onto it. Formula makes a great basic fixed/free hub. It's 120 spaced but you can get it with a wider axle to allow spacing it out to 135 or so if you need to.

I tried pulling a freewheel apart and flipping the pawls. Don't bother, didn't work. My next step will be to either fill it with JB weld or braze it together. Granted, this is a beater polo bike and will never see real riding. If you are going to be doing any real riding, get a new hub.

I can't ever get the chainline spot on
 

Damn. I knew that screwing with the pawls is just going to cause headaches. Though the Surly fixxer hub converter does sound like a good solution for going from cassette to fixed. Yeah, I agree though it's expensive and if I don't have to spend that much, then I won't.

One of my probs on a nice project I'm working on is getting the chainline matched up precisely from front chainring to rear cog. The problem is my unusual setup. I have a MTB with road cranks (actually cyclocross cranks) and 135mm rear spacing. The road crank has a chainline that is a little less than a normal MTB crank. One way, I can deal with this is to convert a cassette wheel into a fixed wheel using that Surly fixer converter you guys alerted me to. Then, of course, play around with adding/subtracting spacers until I get the chainline in the rear to match the cranks chainline. What do you think? Is there a cheaper way for me to do this?

I believe the Surly FIxxer ONLY works with Shimano brand hubs..so it is not a solution for every wheel..

thats true but i guess what the fixxer is designed for is like making some special disc wheel track ready, right?

The Surly fixer does not fix the cassette body, you remove the cassette body and replace it with the Surly Fixer, which has threads for a cog and lockring. Meaning you would still have the same chainline issues.

The options I can think of are:
You can put a spacer on your drive side BB cup to push the chainring further away from the bike.
You can put spacers on the rear hub to push the chainline either way.
You can put spacers on the chainring bolts to move the chainline away from the crank (Either direction depending on if it's on the inside or outside of the spider).
And you can replace the BB.

The fixer also has a history of getting sloppy with time. They sound too expensive for what they are.

If you are having chainline issues you can get a 120 or 130 hub and respace it in the right place. The only drawback is that you will loose the ability to flip or flop. My first conversion had chainline issues and I was too cheap to buy a new BB so I just respaced and redished, problem solved.

Problems matching road crank chainline with MTB 135mm hub chainline
 

Thanks for the ideas everybody.

Ideally, I would like to keep the road cranks on the MTB and not mess with the cranks chainline. The spacer rearrangement of the rear cog is a good idea. But, I thought that it wasn't possible. I mean, supposing I get a new 135mm fixed hub (ex: Surly, Iro, Kogswell, Van Dessel, etc) and the chainline on the rear is too far out. Can I push the rear cog chainline in to match the narrow road crank chainline? Will I be able to push the chainline in far enough to match the road crank's chainline? For some idiotic reason, I thought that the rear chainline can only be adjusted out.

Yes, high tech ;) and yes, hack

To do this, you would need a new axle because you're not going to engage the races properly with the cup forced out like that. Just want to make that clear before anyone tries it.

Screw the non drive side in further.

Sorry to dig up an old thread, but has anyone tried jb-welding short lengths of (thickest possible that will fit) spoke under the pawls? This is on a three pawl wheelset and in theory it could work and testing it it seemed OK. Just seeing if someone else has given it a shot or if I will be the guinea pig.

Since nobody answered, I'll just try it, and if I die, I blame you :)

i did this one time and it kinda worked.

http://i4.photobucket.com/albums/y13...f/fe6c5467.jpg

^thanks for making the lights flicker in my room while you did that.

I mean putting a length of spoke under the pawl tooth preventing it from moving.

I did something similar: I drilled trough the casette body just under the pawls, tapped the holes and screwed in the hardest 2mm screws I could find to block the pawls. It worked Ok when I tried it by hand, the first attempt to backpedal broke the whole setup so I had freewheeling again. I might have had more luck with steel casette body, the one I used was Gipiemme light alloy one.

thanks. I am relying on the pawl's strength (and the ability of stainless to not compress too much) to hold as a fixie mechanism. Only worry is the ramps are more likely to slip than the flats of the freehub body, making slowing down harder.

I guess our setups were simillar - the screws were under the pawls, blocking their movement - I guess that's how you are using your pieces of spokes.

Anything is possible with a MIG welder.

alloy freehub body.......

You don't need a welder, just something to cut spokes with. I will notify about success tomorrow.

It is most definitely possible to convert a freehub to fixed. Locking up the pawls on a Neuvations R series hub with a filed down section of spoke (just so it wouldn't elevate the pawl preventing the insertion of the body (no other interpretations are necessary. If you proceed to interpret that in a non-bicycual way, go **** yourself) into the hub) under each of the three pawls. After 3 km with some skid stops, there was no slipping and it gives me the magical choice of any chainline and any cog that I want, too bad it ain't track legal.