TejanoTrackie 

Watch out Steev, this guy might be a Chinese industrial spy.

Steev

Seems as there's no interest except for me.
I want such a beast for a frame I already have. I'll just go and make my prototype and use it and not bother the forum with it anymore.
By the way TT, vertical drop-outs will fix any wheel slippage issues you may ever have.

cal_gundert05

Or the next Edison.

TejanoTrackie 

Sure, and that's why all modern geared bikes use them. They can get away with open cam quick release skewers that apply very little force such that bearing adjustment is unaffected and there is less tendency for compressional buckling of the axle. However, wheel slippage is only a theoretical problem with track drops if you use nutted axles and tighten them properly. Furthermore, a chain tug or dropout adjustment screws completely eliminates this possibility. Also, nutted axles do not compress the axle, such that bearing adjustment is unaffected and the axle will not buckle. Again, the proper design for the given application.

TejanoTrackie 

Or the next Zuckerberg.

Scrodzilla

FastJake

There was a huge thread about using a chain tensioner on a FG a few days ago. Summary:

- It won't work.
- If it is somehow strong enough to resist the force of the chain when you backpedal, you will probably:
a) damage the chainstay (if attached there)
b) definitely damage your derailer hanger (if attached there)

Because neither of them are designed for such loading. If you've found the magic way to make it work, good for you. But I'm willing to bet money it won't work, especially since you won't say what the idea is. I kinda doubt everyone is lurking BF for the next awesome idea they can steal and make money off of...

Soil_Sampler

zazenzach

whatever you "invent" will not work or be safe. basic physics.

get a frame with horizontal drops, its that simple.

silver_ghost

Are you sure this happens? I've had my wheel slip on a conversion with forward facing dropouts and the tire rubbed the chainstay and locked up long before the axle came out the front of the dropout.

TejanoTrackie 

No, I'm not sure this happens, and it's never happened to me. However, this is the rationale that is used for track ends. I think it would be more likely with very short horizontal dropouts that we used to call "criterium" dropouts. But, this is not going to happen with a properly tightened quick release or track nuts. I have "pulled" my rear wheel on the track during standing starts and seen other racers do this, but never when riding at speed, so the result was just a zero speed tip over and no injury. I may be wrong on this, but I think pro keirin racers in Japan are required to use tug nuts (njs of course) on their rear wheels.

Balefire

Fixed gear tensioner seems simple to me:

Ghost rings work except sometimes the fall out... so make a ghost ring on a little axle that attaches to the chain stay. Done!

91MF

simple.

hairnet

it's called an idler

as seen on tandems for bicycle use:

HandsomeRyan

Do you have a wider shot of this bike. I'm looking at this pic trying to figure out what is going on, I see another idler pulley (i think) in the back and chain going everywhere.

/interested.

seau grateau

Until the little axle gets ripped off of your chainstay. Also, I don't see how the ghost ring would work very well on the typical FG bike which uses a much larger gear ratio than any ghost ring rig I've ever seen.

hairnet

stick a 52 in there