The Single Speed Thread

Thanks Pete J, and yes Im anti tensioner with roller for those wondering, Id rather have a slightly slack chain (that stays on hopefully) then a roller tensioner. I think Ill just be getting a half link and hoping for the best.
 
when you say roller do you mean the DMR style? Would you use a tensioner with a pulley wheel, but not a roller?
 
triples said:
when you say roller do you mean the DMR style? Would you use a tensioner with a pulley wheel, but not a roller?
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Yes, I am opposed to both pretty much. I only want the chain to be running over the chainring and the rear cog, I don't wan't other any devices for the chain to run over, I was wondering if there is some clever way to achieve what I want with vertical dropouts.
 
There a few ways you can get away without a tensioner with vertical drop outs all require a little bit of luck.
1. Find the magic ratio so the that the tension is just right, you may need to use a half link and you'll be limited in gear choice. You'll loose tension as parts wear in.
2. If you're close and there's plenty of metal in your drop outs they can be filed out a little
3. Use a ghost ring (also known as phantom cog). Insert another cog or chain ring in the chain between the chainstays and the rear cog to spread the chain. Less dodgy than it sounds and works suprisingly well. You do need to have a frame with plenty of space to do it. See Dave@'s bike below
118573041-M.jpg
 
Peace

It's posted else where, but I just gotta show it again.

$250 for frame on ebay

$200 for the rear wheel,

the rest are all spares from around the garage
 

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why are there two chains? is it just for illustration, or does it tie in some how with the tensioning. Does this ghost cog idea work on a single chain set-up?
 
Dicky said:
Can't wait to see that built. Pictured fork, or will it be adorned with one of the many tasty old Bombers?
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Picured fork is the plan at the moment, and the 1-1/4" 'Evolution' headtube means that fitting one of the bombers would be a more expensive option than necessary. Could fit a Maintou 2 or 3 if I feel the need to go the soft option.

The stem on there is about 150mm long so an A-TAC may take its place though.
 
Dicky said:
Better still, get him to rig up
a flip flop hub
two freewheels (one left side drive)
and a tandem stoker crankset...


Always wanted to try that.

*edit: just realised that wouldn't work. Dammit.
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Should be able to run at least 4 - double fixed hub + Surly dingle cogs + drive cranks both sides = chain lubing lunacy..............:cool:
 
I would suggest (not having used a phantom cog myself) that a) he's using a nice cassette, perfectly optimised to shift gears and b) that there's not enough additional tension placed on the phantom cog to keep it in place...

Infact, it looks like he's in 32, something high at the back end... I'm willing to bet that didn't last long at all before the chain line dragged it down the sprockets...

*shrug*

Dave@'s setup seems to have been fairly robust, and I wouldn't say he's a timid rider in anyway..

Cheers
Gonz
 
DaGonz said:
I would suggest (not having used a phantom cog myself) that a) he's using a nice cassette, perfectly optimised to shift gears and b) that there's not enough additional tension placed on the phantom cog to keep it in place...
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Yup, you need to have a bit more wrap around the cog to make sure it stays in.
 
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