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AdrianStreet1973":3lhha13m said:
+1.
I'm in the same boat with my '97 stumpy. This thread is answering all my questions.
singlespeed conversion virgin, noob questions !
- Thread starter robadub
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+1.
I'm in the same boat with my '97 stumpy. This thread is answering all my questions.
This
http://eehouse.org/fixin/formfmu.php has been posted, but in my experience it gives you a good indication at best where to start finding a Magic Gear. If you don't have the published chain stay length from the bike manufactuer, then trying to measure it accuratly with a ruler will give you a starting ball park figure. When you've plugged in the info, then try these practicle tips to finalise your Magic Gear:
- put your wanted chain-ring on.
- get your wanted chain ready.
- set up the spacers closest to the hub to give you a reasonable chain line.
- play with old sprockets from a cassette first by simply seeing
if the chain will more or less join. Old 6/7 speed Uniglide road corn-cob cassettes are perfet for trying and perfectly rideable in SS mode.
- if it looks alright, put the remaining spacers on, tighten it all up.
- break the chain to right length and fit it.
- Pop the wheel back in.
If the chain is a fraction too slack, a new SS cog of the same teeth will tighten it up nicely. They have a slightly larger diameter, along with taller teeth.
If the chain is too tight - the wheel won't even engage or marked locking points when you turn the cranks, file a bit from the hub axel - and I mean a bit - so the rear wheel can move forward slightly. See Saint Sheldon: http://www.sheldonbrown.com/singlespeed.html
OR if you are not keen on filling, get your chain back on a normal bike, do a few 100 miles, then try again with the added chain stretch. Riding with no oil will speed up the process :!:
DON'T file the frame unless you are really settled on that Magic Gear on that bike.
Bear in mind that what is seemingly a very tight chain will actually loosen very quick after a few rides in SS mode. Putting new chains on first that seem perfect with a magic gear can quickly lead to a disappointing sloppy chain after a few rides.
If the above doesn't work, then try a chain tensioner. I've had no success really faffing with half-links - but that's just me.
This procedure is not recommended if you planning a visit to the velodrome, but it get's you going on the cheap and plenty good enough for getting a retro conversion started.
I've even heard people having custom chain stay lengths with vertical drop-outs using the above principals since there's no faffing with EBB or fiddling with sliding drop-outs when using disk brakes.
http://eehouse.org/fixin/formfmu.php has been posted, but in my experience it gives you a good indication at best where to start finding a Magic Gear. If you don't have the published chain stay length from the bike manufactuer, then trying to measure it accuratly with a ruler will give you a starting ball park figure. When you've plugged in the info, then try these practicle tips to finalise your Magic Gear:
- put your wanted chain-ring on.
- get your wanted chain ready.
- set up the spacers closest to the hub to give you a reasonable chain line.
- play with old sprockets from a cassette first by simply seeing
if the chain will more or less join. Old 6/7 speed Uniglide road corn-cob cassettes are perfet for trying and perfectly rideable in SS mode.
- if it looks alright, put the remaining spacers on, tighten it all up.
- break the chain to right length and fit it.
- Pop the wheel back in.
If the chain is a fraction too slack, a new SS cog of the same teeth will tighten it up nicely. They have a slightly larger diameter, along with taller teeth.
If the chain is too tight - the wheel won't even engage or marked locking points when you turn the cranks, file a bit from the hub axel - and I mean a bit - so the rear wheel can move forward slightly. See Saint Sheldon: http://www.sheldonbrown.com/singlespeed.html
OR if you are not keen on filling, get your chain back on a normal bike, do a few 100 miles, then try again with the added chain stretch. Riding with no oil will speed up the process :!:
DON'T file the frame unless you are really settled on that Magic Gear on that bike.
Bear in mind that what is seemingly a very tight chain will actually loosen very quick after a few rides in SS mode. Putting new chains on first that seem perfect with a magic gear can quickly lead to a disappointing sloppy chain after a few rides.
If the above doesn't work, then try a chain tensioner. I've had no success really faffing with half-links - but that's just me.
This procedure is not recommended if you planning a visit to the velodrome, but it get's you going on the cheap and plenty good enough for getting a retro conversion started.
I've even heard people having custom chain stay lengths with vertical drop-outs using the above principals since there's no faffing with EBB or fiddling with sliding drop-outs when using disk brakes.
AdrianStreet1973
Retro Newbie
Job done.... well nearly, but we have some hitches.
OK, I posted on this thread a week or so ago about converting my DBR Axis TT to a single speed, and now I've finished it. Well it looks complete but I have a glitch to solve I think. I only jumped on it quickly tonight to see what it felt like and though I could only fit in few pedal strokes around the garden I immediately felt a 'jumping chain'. Like when you put a new chain on an old sprocket. It's all new of course. I've posted a few pics to show what it looks like. Some new stuff on there, so its not all retro I'm afraid. I like the look of it, I just need to sort the jumping chain issue. The drive chain is.
Chainset: Raceface Ride XC SS - 32T
Sprocket and spacer: Gusset Double Six 16T
Chain: SRAM PC1 SS Chain
Tensioner: Superstar Sprung Tensioner - Gold anodised Jockey Wheel
Any clues what's up?
OK, I posted on this thread a week or so ago about converting my DBR Axis TT to a single speed, and now I've finished it. Well it looks complete but I have a glitch to solve I think. I only jumped on it quickly tonight to see what it felt like and though I could only fit in few pedal strokes around the garden I immediately felt a 'jumping chain'. Like when you put a new chain on an old sprocket. It's all new of course. I've posted a few pics to show what it looks like. Some new stuff on there, so its not all retro I'm afraid. I like the look of it, I just need to sort the jumping chain issue. The drive chain is.
Chainset: Raceface Ride XC SS - 32T
Sprocket and spacer: Gusset Double Six 16T
Chain: SRAM PC1 SS Chain
Tensioner: Superstar Sprung Tensioner - Gold anodised Jockey Wheel
Any clues what's up?
Attachments
I have the same problem with my single speed build completed today. Did not have time to sort today but it the first job tomorrow and it only skips under load. I used an 8 speed chain KMC Z82. Rear sproket is a single speed 18T (I forget the brand) and chain ring is a biopace 38T. The chain rings are the orginals but don't look worn and the sproket is new as is the chain. The ratio is perfect and bike is super light.
I suspect yours like mine has a chain line problem. I thought mine was all lined up, aparantly I was wrong or it something else but there really is nothing else.
I hope you sort your skipping problem and enjoy riding it.
I suspect yours like mine has a chain line problem. I thought mine was all lined up, aparantly I was wrong or it something else but there really is nothing else.
I hope you sort your skipping problem and enjoy riding it.
AdrianStreet1973
Retro Newbie
Ok, so it's not the chain line. The tensioner alignment did look a smidge out when I checked it. It's dead straight now, but still it jumps.
I'm suspicious about the SRAM 'snap lock' joining link as when I turn it backwards it makes 'click' when it goes through the jockey wheel. However when I pedal it forwards with the wheel off the ground (no load) it sounds fine.
I wondered about the wrap around, but this tensioner doesn't have a huge amount of range left in it. I could take out a link or two perhaps, but after roughly taking up the available slack to the limit of the tensioner by hand I bearly get an extra tooth wrap around on the rear sprocket.
I might try taking out the joining link tomorrow to see if that improves the problem. Otherwise I might be looking for a new tensioner. But it seems odd because this one seemed well recommended, and it's not fundimentally different to so many others.
Oh and I liked the gold jockey wheel!
I'm suspicious about the SRAM 'snap lock' joining link as when I turn it backwards it makes 'click' when it goes through the jockey wheel. However when I pedal it forwards with the wheel off the ground (no load) it sounds fine.
I wondered about the wrap around, but this tensioner doesn't have a huge amount of range left in it. I could take out a link or two perhaps, but after roughly taking up the available slack to the limit of the tensioner by hand I bearly get an extra tooth wrap around on the rear sprocket.
I might try taking out the joining link tomorrow to see if that improves the problem. Otherwise I might be looking for a new tensioner. But it seems odd because this one seemed well recommended, and it's not fundimentally different to so many others.
Oh and I liked the gold jockey wheel!
