SV 520-Chain-Conversion

[BornToLean]

Finally got the race bike out on the Pukekohe track at the recent AMCC thingy, rider was crap but bike went ok without major problems. However, with standard gearing it was over-reving abit down the back straight. (It's a SV650S in ProTwin 650 config.) It was easily into the red-line around the kink in top gear which is undesirable for the bikes long term health.

So, before I go and buy some different sprockets to tinker with the gearing, what are the benefits of changing to a 520 size?

Thanks in advance

Steve

[riffer]

I may be wrong, but I'm damn sure the biggest advantage is the weight loss.

520 chain and sprockets could save you 2-3 kgs.

[Sully60]

I may be wrong, but I'm damn sure the biggest advantage is the weight loss.

520 chain and sprockets could save you 2-3 kgs.

Not converting from 525 chain, its only a wider chain designed to run on slightly thicker sprockets, you save weight but not 2 or 3 kg. Still any weight saving is good.
Running 520 opens your options in terms of the variety of chain available.
What year is your bike? I know everything up to 07 runs the same chain and sprocket as my original old beast (99) I couldn't find a straight 520 conversion in usable sizes off the shelf. I had my sprockets thinned down to run 520. You should really get them ground as the steel sprockets are fuggin hard and don't turn up on a lathe easily. The other option is using aluminiun blank sprockets, any tooth option you want and you can cut heaps of holes in them to make them light.

[ZeroIndex]

When I did my stunt conversion on my FZR400, I did the 525 to 520 chain pitch conversion after consulting some stunt sprocket manufacturers in the States... Their reasoning for changing to 520 is simple: Engine attaches to front sprocket, which connects the rear wheel and sprocket by a chain... therefore, the thinner the chain (less weight), the easier it will be for the engine to turn the back wheel (less friction/less weight movement at the smallest scale).

Only disadvantage of a smaller pitch chain is strength, but unless it's a power hungry inline4 1000+ or chain snapping big single, there shouldn't be a problem when it comes to mid-range power producing bikes such as inline4 400cc - 600cc or an SV650, as in your case... go ahead... the chains, due to being thinner and lighter will be cheaper too!

[GSVR]

I would think the main reason for running 520 is becuase you can get a full range of sprockets.

You will find that Yamaha has front sprockets with the same spline as the SV.

Try getting a selection of front sprockets in 525 and you will see what I mean!

[GSVR]

Oh one glitch in the ProTwin rules. You are allowed to change drive sprockets but theres no mention of the chain so technically taking the rules to the letter you are not allowed to change chain size.