fixed gear conversion

[ghostpedal]

I am currently getting ready to try converting a regular bike to a fixed gear or single speed. In preparation for this, I have been looking for parts locally and online. On Ebay, I found a part called Drew's Adapter, which is said to properly space a track gear on a regular freewheel hub. Does anyone have any experience with these? Even if you don't, I would appreciate any opinions you might have about the adapter, or any tips, etc. for my project. Thanks.

 

[Gonzo Bob]

I've never heard of a Drew's Adapter. But I did convert a road bike with FW hub to fixed-gear last year.

Chain line is critical. You want it to be as straight as possible. If you just spin a track cog or single-speed freewheel onto a multi-speed freewheel hub, the chain-line will probably be terrible, even with a spacer (unless the spacer also contains extended threads for the cog).

here's what I ended up doing

1. Inserted 3mm spacers between crank and chainring to space it more inboard.
2. Respaced the rear hub - moved drive-side axle spacers to the non-drive side. I had to redish the wheel after doing this.
3. That still didn't give me good chain-line so I also put an english threaded BB lockring on before the cog.

There were not enough threads to put a lock ring on after the cog so I kept both brakes on the bike and don't exert much back pressure on the pedals.

 

[ghostpedal]

Thanks for the info. I am doing a fixed gear conversion, but want as little cash outlay as possible. This is my first fixed gear (aside from an spinner exercise bike) and am looking forward to the whole experience.

I've never heard of a Drew's Adapter. But I did convert a road bike with FW hub to fixed-gear last year.

Chain line is critical. You want it to be as straight as possible. If you just spin a track cog or single-speed freewheel onto a multi-speed freewheel hub, the chain-line will probably be terrible, even with a spacer (unless the spacer also contains extended threads for the cog).

here's what I ended up doing

1. Inserted 3mm spacers between crank and chainring to space it more inboard.
2. Respaced the rear hub - moved drive-side axle spacers to the non-drive side. I had to redish the wheel after doing this.
3. That still didn't give me good chain-line so I also put an english threaded BB lockring on before the cog.

There were not enough threads to put a lock ring on after the cog so I kept both brakes on the bike and don't exert much back pressure on the pedals.

 

[Velo Serg]

I am currently getting ready to try converting a regular bike to a fixed gear or single speed. In preparation for this, I have been looking for parts locally and online. On Ebay, I found a part called Drew's Adapter, which is said to properly space a track gear on a regular freewheel hub. Does anyone have any experience with these? Even if you don't, I would appreciate any opinions you might have about the adapter, or any tips, etc. for my project. Thanks.

Here is all I did, no redishing, no tensioner.

I found a wheel with a thread on cassette that was the right rim diameter for my bike. Plenty can be found in 26" and 700 if you look. Then I bought a BMX freewheel and threaded it on, a track cog would work as long as you use a lockring. To align the chain I found a dished chainring, probably from a 2 speed MTB crank, and installed it so it was dished in. Check for frame clearance, you can't go too big on most frames. Unless the bike has purely vertical dropouts you will have enough play, you just have to mess around with different sized cogs gears at both ends. With track cogs it is easier, as in cheaper, to experiment until you get a size that gives you the right tension. One good thing to remember is that once you find one combination of gears that works you can change as long as you add or subtract in multiples of four, or two if you use a half link. If possible I would suggest starting with one or two chainrings if you can and three or so track cogs relatively close together, like a 16, 17, and 18. Mess around long enough with those and something will fit. Then if the gear ratio is not what you want you can move in steps of four.

 

[ghostpedal]

Thanks for the advice. Since this is my first fixed gear, I want to do it inexpensively. I can always move up if I love it.

Here is all I did, no redishing, no tensioner.

I found a wheel with a thread on cassette that was the right rim diameter for my bike. Plenty can be found in 26" and 700 if you look. Then I bought a BMX freewheel and threaded it on, a track cog would work as long as you use a lockring. To align the chain I found a dished chainring, probably from a 2 speed MTB crank, and installed it so it was dished in. Check for frame clearance, you can't go too big on most frames. Unless the bike has purely vertical dropouts you will have enough play, you just have to mess around with different sized cogs gears at both ends. With track cogs it is easier, as in cheaper, to experiment until you get a size that gives you the right tension. One good thing to remember is that once you find one combination of gears that works you can change as long as you add or subtract in multiples of four, or two if you use a half link. If possible I would suggest starting with one or two chainrings if you can and three or so track cogs relatively close together, like a 16, 17, and 18. Mess around long enough with those and something will fit. Then if the gear ratio is not what you want you can move in steps of four.