i need a piston

[mxracr6]

i have a 2004 trx400ex taht was built before i got it.anyways,i broke the piston and tore it down to find that it is bigger than any other 400 i have.the rod is +4mm, cylinder sleeve is 90.010mm,and the piston is 89.99mm.can anyone tell me what piston to put in this thing?all i can find is 89mm pistons that fit 440 kits,and they are too small.

[CSR400EX]

is there any part numbers on the piston?? that bore and stroke comes out to a 470!!! how did it run before you took it apart????

[mxracr6]

the nly numbers on the piston are .25,quarter mil over,and a casting number on the inside skirt 404.it ran like a raped ape!i never opened it all the way.

[CSR400EX]

its hard to say what kinda piston it is. could you possibly post a picture of it on here, that could possibly tell us, or someone might recognize it.

[suzukiray]

Call CP Pistons at 949-567-9000. They make the BEST you can buy! Ray.

[mxracr6]

does anyone know how i can get in touch with mickey dunlap@4stroke tech in pa.i was told he could get me that piston by ritter racing.obviously that piston came from another motor and he shaves the skirts off to fit.

[CSR400EX]

this is their number, (814)842-6159. it says on their site they only answer between 4 and 7 EST.

[boosted3g]

I think it was Wiseco that offers an 89.25 piston. Worst case resleeve it again, c&d does a kit for about 245. Thats piston, sleeve, bore and gaskets.

[CSR400EX]

Originally posted by boosted3g
I think it was Wiseco that offers an 89.25 piston. Worst case resleeve it again, c&d does a kit for about 245. Thats piston, sleeve, bore and gaskets.
he said his piston measured 89.99mm, so thats 1mm over. i havent heard of a piston that big for a 400EX lol.