Singlespeed & Fixed Gear - Chain wear and cranksets.

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View Full Version : Chain wear and cranksets.


europa
12-20-08, 07:22 PM
I recently commented on my rear wheel slipping in the dropouts, based largely on the way the chain kept going loose. Turns out it wasn't the wheel moving, though it did once or twice which lead me to believe it was doing it more often. From new, this chain has needed tensioning at every second fence post. I did a quick measure the other night and guess what, it's already 'stretched' by a fat 1/8". The flamin' thing's knackered.

That happens of course ... but this chain is only 600kms old :eek:

Yes, it has been cleaned and oiled and looked after using the same methods that get a few thousand kms out of the chains on my geared bikes. Much as I'd like to blame neglect, I can't.

The rear cog was a new dura-ace (1/8" as was the chain).

The chain ring and crank are the Ofmega offerings that the bike was sold with. Although the chainring doesn't have the pointy teeth and odd shaped 'hollows' of a worn out chain ring, more careful examination shows that the corners of the teeth are quite well shamfered. Just what you'd expect of course with a chainring that old. It's also 3/32 though I don't know if that affects chain life.

I'm blaming the chain wear on old chain ring and a cheap chain (just a cheapy bmx item).

Any thoughts on other causes for the short chain life would be appreciated.

Rather than just throw a new chain at the bike, I'm going to shout the old girl to a complete drivetrain - BB, cranks, chain rings, chain and cog. Any thoughts and suggestions? Local availability of items will affect what I get so Aussie input would be appreciated (there's an Aussie, specialist fixed site on the web isn't there?).

Richard


Geordi Laforge
12-20-08, 07:49 PM
just get a new cog and chainring.
unless you have some cash to spend or there is something wrong with the cranks and bottom bracket.

europa
12-20-08, 08:01 PM
just get a new cog and chainring.
unless you have some cash to spend or there is something wrong with the cranks and bottom bracket.

That's the rational answer and if all I was chasing was chain wear, you'd be spot on.

In this case, the old crankset is probably a little flimsy and the bb has done a lot of work - it's rebuildable and has been rebuilt a few times. I have no doubt that there's a lot of life in her but I'd like to start fitting some new bits over time. The frame needs a repaint too but I don't want to lose the original stickers so will have to find someone who can make me a new set.

You're right, I don't NEED a new crankset and bb, but there's some emotional justification for it and if I'm going to do it, now's the time to do it.

Richard


Ken Cox
12-21-08, 06:21 PM
Check with www.businesscycles.com for a Stronglight crank.

The Stronglight takes 130mm chainrings, which allows you to use a wider variety of chainrings (use only inner chainrings or chainrings specificially designed for single chainring setups).

Ask John to recommend a bottom bracket.

I suggest an EAI 3/32 cog and a KMC Z610HX chain.

sp00ki
12-21-08, 06:40 PM
lols, you said "knackered".