Wanted: Chainrings for three pin Cottered Cranks. Double and single.

Looking for chainrings for two cottered cranksets. Good cosmetic condition preferable but not overly vital if you have something steel and inetresting as I can always rechrome.

Double chainrings to suit a Fratelli Brivio cottered crankset. Similar to this model.

• 116mm BCD, preferably 3/32", flexible in terms of chainring brand and pattern.
  
  

Single chainring for a Durax cottered crankset. This model.

• 116mm BCD, 1/8th", flexible in terms of chainring brand and pattern.
  

got a bb if you want :)

i think i've got some some lurking - not sure what i've got though. hang on and i'll go and look

got a bb if you want :)

Thanks, what type is it? Probably sorted for BBs. I've got a decent selection of cups and axles. Although my eyes are still peeled for quality ones. And, always looking for hollow cottered axles.

i think i've got some some lurking - not sure what i've got though. hang on and i'll go and look

Cheers... let me know when you've had a chance to look. No rush.

have a pair of Stronglight 116bcd taken off a pair of steel S/Light cottered cranks will check sizes and get back

Cool. Sound interesting.

this is what i have - i know nothing about cotter pin tech but i'm guessing it's not what you're after - happy to freecycle if anyone does want it though

http://www.lfgss.com/thread83304.html not long posted

this is what i have - i know nothing about cotter pin tech but i'm guessing it's not what you're after - happy to freecycle if anyone does want it though

Yep, not what I'm after. Those look the type that one ring and the arms are all one piece. But thanks for looking. Appreciate it.

http://www.lfgss.com/thread83304.html not long posted

Thanks for pointing those out. I'm ideally looking for something with a slightly more elegant shape. But may change my mind if nothing else shows up.

I have some durax/williams rings
Would have to check bcd
Malc

Cheers Malc. Just let me know. Durax would be excellent. Williams might be fine too.

If it helps anyone look, for 116mm BCD, the distance between bolt holes c-to-c on the chainring is pretty much 10cm.

Hi
Just checked the williams chainrings
Measured bcd approx 77.4 mm
Not sure how you work it out

1/ 52 tooth
2/ 48 tooth
3/ 46 tooth

Yeah sounds like they'll be too small. Nevermind. Thanks for looking, appreciate it.

Regarding working out the BCD...

If you measure from the centre of one chainring bolt hole to the next, it would be just over 100.4mm for 116 BCD.

You can work out BCD from the centre to centre measurement by x 0.155 for three bolt chainrings.

eg. 100.4 x 1.155 = 116 BCD

working the BCD out is straightforward using this formula
Multiplying distance between bolts by 1.701 will give you the actual BCD for a 5-bolt chainring.
Use 1.155 for 3-bolt chainrings, 1.414 for 4-bolt chainrings and 2.000 for 6-bolt chainrings. (ref: Sheldon Brown)
hope this helps