2010 Piston in 09 KX450

Was wondering if anyone knows if the new 2010 Piston will work in a 09 KX450. Thanks.

if part numbers for the head and cylinder match up...then go for it.

I doubt the part numbers would match up, considering its a brand new design.

I was wondering that myself though, for all the KX450Fs 06-09.

Someone needs to take some measurements.

the reason it won`t work is because the crank is a new design, the piston is lighter which will throw your engine out of balance also, you will probably go through crank bearings like crazy because of balance issues

The piston being lighter should not affect your crank. Your crank is balanced with your rod. So a lighter piston would let it rev up a little faster.

Wiseco 12:1 piston+pin for the 06-08 is 9% lighter than the stock OEM cast piston and its pin. Done over a 100 hrs on one of these in my 06. Revs nicely. No bearing noises.

the reason it won`t work is because the crank is a new design, the piston is lighter which will throw your engine out of balance also, you will probably go through crank bearings like crazy because of balance issues
The piston being lighter should not affect your crank. Your crank is balanced with your rod. So a lighter piston would let it rev up a little faster.

The piston is actually a critical part of the balance factors...so it does make a difference.

That said 10 grams wouldn't be much of a change.

I wonder if the crank/balancer would need to be reshaped with falicon rod/wiseco piston as together they weigh quite a bit less.If I remember correctly the knife rod was 35-40g lighter than the oem,then add up the piston and your close to 50g.

If I remember correctly, the Wiseco 12:1 piston+pin+clips+rings is closer to 27g lighter than the OEM parts. Like 335 vs 362g.

Yes, a 2010 piston will work with 09's only.

have you personally tried this,just curious cause i may try it myself.thx.chris.

The cylinder and cases are changed too. Are you guys sure it will clear everything?

My source is Team Green Off-Road. Haven't personally tried it..

the piston for 2010 works with the 2009, confirmed with kawasaki headquarter...i have orderd one now...

Anyone know if Kawi make their own forge slugs for their 2010 pistons?

It would make sense if they do since it means it took 4 years for them to spend the money to tool up to make them. But on the other hand they might have said "that's enough, and let's buy pistons from somewhere".

i have just mounted my new 2010 piston in my 2009 motor, and it works fine as hell, did it alone aswell, a very easy operation, did it on 3 hours....

Make any changes to power / delivery?

Make any changes to power / delivery?
maybe it rev up a little faster....but i dont know for sure...the new piston are 30 grams lighter...i had 30 hours on my old piston no sign of wear...i can put it back in when i change next time with new rings...

I also have an 2010 piston in my 09.....works perfectly:thumbsup:

The piston being lighter should not affect your crank. Your crank is balanced with your rod. So a lighter piston would let it rev up a little faster.

Anytime you balance a crank the piston, wrist pin, clips, rings, rod and crank is weighed. From there is a balance factor and percentage used to balance a crank.

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