sprockets sizes
 

I was considering getting new sprockets and a chain i saw a 520 chain conversion kit does anybody know what the standard size is. The other thing is i notice at 135 mph my bike was out of power but still had a little bit of room left on the tach does any one know what the ideal sprocket sizes are to get a little more bite and not drop the top end much if at all.

I've actually JUST ordered a new chain & sprocket set.

If you want to gain top speed, you will loose some acceleration. If you want to gain acceleration, you will loose some top speed. I chose the latter.

For me, this went from a 44 tooth standard rear sprocket to a 46. Which is the same as going down a tooth on the front.

Check out the "Looking for a new chain" thread for specifics of what I opted for.

Do a Search!

Read this thread from yesterday http://forums.sv650.org/viewtopic.php?t=49858

Look on the linked websites.

Going up one on the rear will give more 'bite' for acceleration and you might not lose too much top end.

I don't think you'll lose any top end, since you're not able to use what you've got now ;) 15/45 is what I use, it's not much different from standard- in fact, it was standard on the SV650Ns, carbed model at least. If you want a big change, you'll need to go further.

SV650S 15 front 44 rear 520 pitch chain
SV650 15 front 45 rear 525 pitch chain

(I THINK)

if you're going for a bigger rear sprocket on an S you'll need the longer chain

Hope that helps

some people on here have gone 14t front and 47/48 rear, and all combinations in between

I've just ordered a 46 rear sprocket, and the standard one is 44 teeth. No need for a longer chain (or so B&C told me when I ordered on the phone). If you go up more than 2 teeth, then yes, you'd need a longer chain, unless you went down on the front as well.

I'm assuming the front is 15, so I'll be using a 15/46.

Baph,

Be careful with that set up, and don't hold me to anything BUT

The chain may fit those sprockets, but as i understand it, it MAY cause excess chain wear if your chain is too short - but don't hold me to it :wink:

If I change from a stock set up to a 16 tooth front sprocket, will the chain be long enough?
I have an '01 SVS.
thanks,
Oldie

I think so, but why go up on the front, that'll make your bike accelerate slower, and in theory have a higher top speed

I fitted a 16T on the g/box on my 01 SVS not long after getting the bike new, so the chain was still more or less the original length.

It will fit with the std chain (and std 44 rear) but there's not an awful lot of spare movement at the wheel spindle, shouldn't be any problem though.

If you want significantly more top speed you need a different bike I'm afraid. Power requirement goes effectively with the speed cubed, so going from 125 to 130mph (true speed) requires about 12% more power, and going from 125 to 135 requires over 25% more power, which you won't wring out of a SV650 without spending big money.

A 520 chain has slightly narrower rollers (1/4" vs 5/16"), is all. In theory, less powertrain loss.

Thanks for the info regarding chain length. I'm not trying to go faster, I just want to drop the revs a bit. At the moment, I'm always hunting for a seventh gear!
I'm an old bugger and the SVS is plenty fast enough for me.

Oldie

That was my feeling exactly (also an old scrote :oops: ). Sounds like going to 16T will do exactly what you're after. Since having the 16T on I can't recall ever having tried for 7th, but I did all the time when on std gearing.

I find myself looking for 7th quite often too. However, this is mostly around 20miles before the fuel light starts flashing, she just sounds to be revving higher because of more air in the tank, but it's a good indication of fuel levels. I don't only hear it, but also feel it.

And I've just gone up 2 on the back to get it quicker off the line :D

Std chain is a 525. For road use stick to this as the 520 conversion wont last as long.


Adding a tooth on the rear is like taking two off the front. More on the rear, more grunt. Less on rear more top end.

SV650Racer, I think you meant adding a tooth to the front is like taking 2 off the rear, in truth its more like taking 3 off, since 15/16 = 45/48.

a popualr mod for the aprilia 125s is drop it a tooth on both sprockets. has anyone tried this for an sv

by dropping a tooth at the back you'r almost cancelling out the tooth down at the front, 1 tooth down on the back would make things less harsh than with just 1 tooth down on the front, but to me seems a little pointless, unless it lets you keep the standard chain length?