We have an 06 450f that had the piston crack, pulled it down, but noticed when removing the cams I set it on topdead center, and the intake cam lobes were pointing more back than up compared to the exaust lobes, have seen this on a few 250f's but not heard of it on the 450, pressed off the gear to examine it, and it is like the 250fs no dowel or keyway, just pressed on, We thought it was down on power for a bit, but figured it was due for some top end work, There is a hole in the sprocket that should correspond with the holes in the lobes, it was off about 1 and 1/2 teeth, reindexed cam by measuring the top of the exaust lobe to the cyl deck while pointing slightly upwards towards the front of the engine, on top dead center, then set the intake cam the same way pointing slightly upwards towards the back of the engine, thats how I set my 250fs that had the problem in 04 and 05. will place a spotweld on them now, No apparent oiling problems or cam scoring, all parts looked great and moved freely, was a crack across the piston, but figured that due to oil being forced from the breather when we kicked it due to crankcase pressure, if anyone has a cam out or an engine apart, please verify the hole in the cam sprocket lining up with the hole in each cam lobe in a line lookin down it, thanks:bonk:

I don't want to direct you in the wrong direction, but a friend thought the same thing. If you look through the hole, the cam lob should line up. I would contact Kawi just to make sure...

measure the cam timing if you want to be SURE. Tack weld the gear once the timing is set where you want it.

Your not, It doesn't line up, removed the sprocket and reindexed it, this cam has never siezed Its never had a problem that wasn't minor in two years, It has shifted a little bit over time is all I can conclude, have had the same issues with the 250f in 04 as well as 05, talked to Dan at crower today and he gave me the same info they should line up with one another, I went ahead and set it in correspondence with the measuerments on the exaust, will spot weld it tonight, end of issue, My sons were sayin they thought it was down on power a while back, guess they were right, will fix that finished rough port last night will polish tonight, ordered the JE 13.5 to 1 piston and a new cam chain valve springs and seals and a complete gasket set,

cam is reset and welded went ahead and started porting and polishing, just a little more and I'll finish the cylhead, heres a few photos

heres a few of the head

pictures are to large makes them a little blurry, sorry

"polishing" the intake is not the hot ticket. On the ex side it's fine, basically discourages carbon from attaching it's self to the port walls, which it will do anyway.

On the intake a smooth "rougher" finish is what you're after. When i say rough i mean finished with sand paper, not a carbide burr. :)

The intake is not polished, the exaust is thanks for the tip, believe I have that part under control, will admit the kawi does have an awful smooth intake tract, but its not been touched, thanks for the advice though

art5 said:

I just ported the exhaust also and man did it make a difference.:applause:

You can come and see this weekend at Covington Tn. at Hidden Valley race park.:ride: :ride: :ride: :applause:

art5 said:

Cool, sorry man hard to tell from the pics.

The newer Kawi heads are quite nice, especially the ex port.

Have you done any valve seat work?

nope the seats and valves look great not moved in 2 years the bike has been bullet proof

art5 said:

That’s awesome.

I asked because when I port a head I usually add a 5 angle valve job, narrow the seats and place them on the edge on the valve face....while you’re in there......

Ronin 26 said:

I only did this on my dragbike.Don't want to take it to the edge on a dirt bike.

Thomas6x said:

They only work better with a concentric seat at the proper width. But yeah it is more work.

Checked the valve clearance today and noticed the same thing,the holes are a bit off on the intake cam,maybe one tooth max.The bike makes good power and starts easy.Is there some kind of alignment marks for the exhaust cam?

Will take it apart,let the shop correct it and spotweld it.