I suppose you COULD run a rotafixed cog on a freewheel thread with a BB lockring without too much trouble at the track.

But only the track.

As dirtyphotons pointed out, most if not all velodromes have rules that specify you must have a lockring installed on your bike.

I use double stepped hubs that have a lock ring on both sides for a fixed and fixed set up and even on a conversion with horizontal drops you usually have room for a 3 tooth difference in cogs.

Although I could run a freewheel I prefer the fixed / fixed set up on all my bikes.

If you want to take a bike like this out on the road you really need to make sure things are set up right... besides the rotafix the cog and lock ring will need red loctite and one should be running a brake.

My Peugeot has been rocking a suicide hub for well over 10,000 km with nary a problem and removing the last cog required the use of a torch and a few extra hands since it was so solidly affixed.

You're absolutely right about the additional steps for road use. I was just assuming track use. Personally I'd never run a suicide hub.

this post got me my senior membership status...

Older frames with long dropouts have plenty of room for 4 or 5 tooth difference. You'll rarely ever want such a spread in real life. Maybe 2 tooth difference.





Formula fixed/fixed hub with 16/18 Surly Dingle and 16T freewheel. Yes, freewheel cog fits nicely on the hub. If you look closely, you can see an old bottom bracket lockring I put on the hub first as a spacer.

Dingles are the shiat! So glad the lbs set me up on my remodel.

Looks like you should drop a link. You can't move the wheel any farther back in the dropout, and you'd need to if you wanted to use the smaller cog.

Congratulations .

If for some reason you wanted more spread than your dropouts could handle, it wouldn't be a big deal to carry an little bit of extra chain and a 2nd master link. Might add 30 seconds to the gear change process.

^that works.

the bike polo crowd tend to desire a normal street gear and a super low polo gear. one setup that has become popular has been to run a surly double cog (17/21) and a double chainring (say, 46/38). that gives a whopping spread of 47.6 and 71.1 gear inches with one chain.

this can also be accomplished with a freehub for a singlespeed. or a regular flip flop hub, creative use of spacers and a double crankset.

It looks like he has a double chainring. He probably uses the smaller cog with the bigger chainring.

You're right. I didn't notice the second ring in the chainline shot.