Single speed cranks?

Quoth lemmiwinks:

Quoted message said:

Ta. I just realised I've got some worn out Shimano Biopace cranks
that could be pressed into service except the biopace rings are
elliptical (only the middle ring is worn out) so probably not good for
hub gears. I tried to get a replacement chainring from the LBS when
it wore out but they baffled me with BCD figures and generally didn't
want to help (I still consider this preferable to the thinly veiled
hostility they normally exhibit).

Biopace triples use the same ubiquitous 110 mm BCD (Bolt Circle
Diameter) as "new" compact doubles. There are squadrillions of rings
available in the 110 mm BCD.

You've most likely got a 48 tooth ring on that set, give it a try.
You'll probably need to put it on the "middle" position for good
chainline, if you're using the original BB.

Try it, you might like it. I do. I have Biopace rings on both of my
own Nexus 8 bikes.

Sheldon "Biopace" Brown
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| Most things having to do with fixed-gear/SS are bone stupid, |
| and folks who usually work on modern bikes aren't used to |
| thinking at that caveman level. -- Aaron Meberg |
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Harris Cyclery, West Newton, Massachusetts
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[email hidden said:

"]I'm after a 39T single speed crankset to go with my Nexus Inter8 hub
the LBS is building up for me. They offered the Shimano recommended
crankset (@$170) which includes outboard bearings. I'm somewhat of a
luddite (I've only just installed a cartridge bottom bracket to trial)
and apart from the excessive cost I just don't like the sound of this
newfangled outboard bearing nonsense.

Can anyone advise me of some plain-Jane square taper 170mm single
speed cranks preferably with a 39T chainring? Doesn't have to be
online, but online is ok, a brand name that I can give to the LBS
would do (though they are very much like the Soup Nazi (http://
en.wikipedia.org/wiki/Soup_Nazi) in there so I'm almost afraid to ask).

Square taper fixie cranks? Campy Pista? Dura-Ace Track? Sugino 75? Or covert an old Shimano or Campy square taper by running single ring where the inner ring would normally go.

Square taper is coming back I tells ya... narrow q factor, less bearing friction... the world will wake up to it's brilliance...

flyingdutch said:

you'll need something at least vaguely built for the job.

Preferably running a tougher chain. IE track or BMX chain.
That means perferably a thicker toothed chainring. Anything less will struggle and possibly wear and/or snap

The Alfine chainset that the LBS is recommending is rather good and a steal at that price IMHO.

Alternatively, if you're a cheapskate, use a bmx chain, bmx cog and the inboard chainring on an old road crankset. Use it till it wears out, then replace with the cheap, slightly more correct alternative... I'm still waiting for mine to wear out after a year and a half of daily commuter punishment.

Ritch

[email hidden said:

"]I'm after a 39T single speed crankset to go with my Nexus Inter8 hub
the LBS is building up for me.

I replaced the Stock Shimano cranks (non-replaceable chainring) that came with my Nexus 8 setup on my Avanti Blade with a pair of Campy Mirage road cranks. The chainline for the Nexus kit is such that if you put the 39 tooth chainring on the outside, it all works perfectly.

The Mirage cranks I bought use steel chainrings, which are essentially indestructible. Just the ticket for a commuter that's used and abused.

Tho looking on the net I note they've changed all their cranks (including Mirage) to the new high-zoot-factor ultra-torque thingies, so they're likely not to be quite as cheap.