Camshaft Swapping

I have noticed that according to Kawasaki, the intake cam has more duration and lift than the exhaust cam.

Intake - .327" lift and 237 at .040" duration
Exhaust - .296" lift and 229 at .040" duration

Would it be possible, with the use of adjustable cam sprockets to use an intake cam on the exhaust side for a small performance increase?

I have an electronic tach, so the tach drive is no problem.

I would also be running and andrews 2x cam in the intake side.

-Dave

With the Andrews 2X cam on the intake the stock intake cam on the exhaust side would do well. The 2x is .360 lift and with the .327 exhaust you will have very good low end torque. If you clean up the ports on both the intake and exhaust side it will be even better. If you have a set of 26mm carbs, try to find a set of 28s or a set of CV34s. That will improve your top end significantly, without spending a fortune on Smooth bore carbs. I run a set of modified CV34s on my GPZ1100 and I can clean the clock on most bikes that run smooth bores.

Lobe center settings with this combo?

I'm running 1075cc 10.25:1 Wiseco, Mikuni RS34 carbs, ported head, Kerker 4-1, stock valve sizes, Dyna S with Dyna Coils.

-Dave

With the Mikuni RS34s you are way over-carbed for that size engine with a stock head and valves. The CV34s are equivalent to 31mm smooth bores. I have a 1150 11:1 MTC kit in mine with a 84 GPz1100 head and oversize valves. Ported and polished head running about 93CFM at 10"H2O pressure. The best your stock head will do is about 69CFM. The oversize carbs will cause more trouble than good on a motor that small. If you were running a 10,000+RPM drag motor, that would be a different story but you have a street motor. I find that my CV34s are the exactly perfect size for my motor. You would have to do a LOT of work to that head for it to be able to use the carbs you have. with .400+ lift cams and oversize valves with a LOT of porting and a 1200 motor you might be getting there.

Using available formulas, the MOST my bike can ingest is about 200CFM of air. The most your bike can ingest is about 165CFM of air. Yor carbs flow about 109CFM EACH. That's 436CFM for an engine that can only ingest 165?? And that is best case scenario. The VM34BS CV carbs flow about 92CFM each. Still a lot more than your bike (or mine) can ingest.

Thanks for the info.

I understand that my carbs are technically too big for the engine combo that I am currently running. It mainly manifests itself as being a little boggy below 4k RPM, but anything above that and it runs just fine, with almost no dropoff in power before I get scared and shift at about 10K.

Personally, I hate CV carbs. I find that slide carbs are more intuitive to jet as I slowly upgrade the engine, changing jetting to suit as I go along.

I bought this bike a year ago, and it came with the RS34s on it. They work, and I like them, so I'm just gonna run 'em.

But back to the subject - lobe centers. What are some guidelines for selecting them, and how does my selection change based on the types of cams I run?

-Dave