Is there a lighter weight chain conversion for the RD's? 530 chain seems a little heavy for these bikes; I see the newer 400's at the track with lighter chains on them, they look almost like bicycle chains, and those are a higher HP bike, so I was just wondering.
https://www.economycycle.com/product/group-520-chain-sprocket-conversion-kit-for-rd250-350-400/
Ahh, sweet. I'm pretty far from needing it at the moment but thanks.
Still looking for a set of Denco pipes and some other doodads.
dencos are basically impossible to find, give up on that. i actually am in possession of a set, took almost a decade to get. i plan on measuring thrm up so they can be reproduced, but they are, from what ive seen, the rarest street pipes for rds ive ever seen that weren't one offs
Ive done the 520 chain conversion with different gearing. Non o and x ring chain too.
what are the advantages of goin to a 520 chain
Quote from: kar1zma on July 23, 2026, 04:29:49 PMwhat are the advantages of goin to a 520 chain
Less weight and less drivetrain loss.
Not to be argumentative, but does it actually make any kind of measurable difference for anything other than racing?
I'll go ahead and say "probably not", at least as measured with the butt dyno. But chains and sprockets are wear items and need to be replaced periodically, so why not shed a little weight and rotating mass when it's easy? You're going to spend the $$ anyway.
Quote from: kar1zma on July 23, 2026, 04:29:49 PMwhat are the advantages of goin to a 520 chain
You are asking the wrong question.
Rather: What is the point of 530 chain and sprocket on a 50 year old 350-400?
Answer: None whatsoever. 520 is fine on 100 hp bikes. So perfectly fine on even the hottest RD.
Standard 530 vs O-ring 520
520 chain is more than enough for any RD. Why carry the extra weight.
if i could have gotten away with a 428 on the lightweight i would have. i looked into it but .. :devil:
Quote from: m in sc on June 22, 2026, 03:59:34 PMdencos are basically impossible to find, give up on that. i actually am in possession of a set, took almost a decade to get. i plan on measuring thrm up so they can be reproduced, but they are, from what ive seen, the rarest street pipes for rds ive ever seen that weren't one offs
Back in 2011 I sold an RD that had Dencos on it, should have just sold the bike and kept the pipes. Anyway I know there's at least one more set out there in the wild.
Quote from: m in sc on August 01, 2026, 02:33:05 PMif i could have gotten away with a 428 on the lightweight i would have. i looked into it but .. :devil:
So what did you find out, just out of curiosity
428 couldn't handle more than about 35-40 hp max for a top of the line chain, and that's in karting applications. so short life anyway. The motor i put in is at least 50 hp so would have been a no go. also, the grom guys would start lunching 428 chains when they got around 30 hp, so i saw it from them as well. not worth the potential risk of slinging it into my cases