Curvy Cam Swap

[Serdna]

I put the bike back together and rode it for the first time with the new cams (from a 2010 sv) today. I made this thread just to say, if you get the chance to do this mod to your curvy, DO IT!

My butt dyno registered more power across the rev range, and a huge surge in the powerband that definately wasn't there before. Also you can hold gears to the redline because the power doesn't drop off.

All in all very happy, worth the effort, time and money spent.

One note, 4 out of my 8 valve clearances were out of spec before the cam change, i dont know if that has an affect on performance, but all are in spec now.

[johnnyrod]

It's ace isn't it? On the track you have a proper chance of beating up the 600/4 boys without resorting to Bloodrunner-style kicking them off or magnetic stick grenades on the tank.

[Serdna]

I can believe that. It feels like some one just poked my bike with a stick and woke it up!

[manicjazz]

So jealous, are these things a bit rare (read pricey)?

[Serdna]

You have to keep an eye out for the K3 onwards intake camshafts, you wont find them easily. I bought an engine and will break it to make the money back.

If you're interested this is worth a read. If you can adjust your valve clearances you can do this.

http://www.bayarearidersforum.com/forums/showthread.php?s=&threadid=154847

[manicjazz]

How about the sound of the engine now? More agressive or throatier?

[Serdna]

Actually now you ask it seems much smoother. But that might be to do with having clearances in check.

[johnnyrod]

no real difference to be honest in sound etc. For me the cams brand new from Suzuki were about £140. I didn't need to adjust any clearances (before and after were the same) and a check on the dyno showed it didn't need any further work. It really is a good mod.

[Serdna]

My clearances were out before i changed the camshafts. In fact i think it was 5 clearances were out. All tight.

I suspect that was the bikes first valve check at 30K miles.

[johnnyrod]

If you want more noise, get a different filter. The ignition advancer Woodruff key added a bit of crackle as well I think. The bext noise was a guy at Oulton Park coming over and saying, "Have you got a kit on that? (as in 700cc) I kept thinking 'I'll blow him away on the next straight' but I couldn't quite manage it."*

* This was in novices so willy-waving rights are fairly minmal!

[Serdna]

I have a new K&N filter i bought a while back in the garage. Can i just put it in the bike or will i need a rejet? I have a stainless devil system with baffle out. It was the next thing on my list to do. My bike hasn't been on a dyno.

Is it worth sticking the K&N on ebay and getting something else?

[johnnyrod]

I've got a K&N in mine, the first ones for the curvy were worse than stock but I'm told they fixed that. Not sure it's worth the trouble chopping it for a different one though, someone else could tell you. A bit of dyno work wil be in order to get the most from the zorst, though not sure you'll see any greater gains with the baffle out vs. in. Dunno about Devil but if I take the baffle out of my Quill it's about a million dB.

[Serdna]

With my Devil its zero dB with baffle in and not silly but not serious levels of dB with baffle out. (But not legal)

I ran the K&N yesterday for a bit. My god did it destroy my fueling! Ran v lean. I swapped it back to my old filter for now. Next month I will fit it and re-jet.

Did you notice a power gain with your K&N? Do you have the pannel one or the one that looks like the OEM curvy filter but different colour?

[manicjazz]

how do you know that it is running lean?

[Serdna]

I guessed. Its a much more free flowing filter than stock. When i put it on it ran really badly. Sluggishly, it had less power and the exhaust popped a bit more than normal. I cant think what else it could be doing. :)

[johnnyrod]

It showed about 72bhp on PDQ's Dynojet dyno once set up, which wasn't a lot more than when they first put it on, but it all works now, snappier throttle response etc. It needed a Dynojet kit (£££). I, think my K&N looks like the stock one, I don't look in there very often! It needs cleaning every other year, this 30,000 miles stuff is just BS. Easy enough to do though. After adding the cams it went up to about 81bhp but again on a Dynojet dyno, a/f stayed the same which is a nice bonus. The dyno set-up was done with Akrapovic zorst and K&N.