coopers

[k2000x]

reading a test last night about coopers enduro 250...they said that dt 250 cylinder and piston bolt straight on...could help with easy find parts from yamaha

[BETRIC]

The only parts that fit a Cooper from a Yamaha are the DT1 piston BUT you have to move the pins in the ringlands of the piston so the ring gaps don't touch the ports and take 4mm off the bottom of the piston skirt, the gudeon pin and clips and DT1 head gasket fit, the barrel will not fit, the conrod is a different size, MOTO ISLO made their own copy of the DT1 piston for the Enduro bike, A GYRT DT1MX single ring piston will fit without modifying as they were installed as standard in Cooper MX bikes. 

[head]

I had a 250 cooper that I fitted a DT2MX Cylinder, piston and head. Fitted straight on no mods. Any of they early top ends will fit. Went heaps better as well. YZ250A would even fit, if you could find one.Early DT might be best bet.

[asasin]

in the cooper I race i use a KTM 300 piston as they are easy to get and the skirt deal is no problem even gives a bit longer inlet timing which helps, just watch the top squish. i run 3 barrel gaskets to get good power across the range. i Dont know what DT barel you had HEAD as I just tried it again ( have another cooper with a DT 250 in it ) and there is no way without modifing the crank cases for the  studs that a DT250 barrel fits on.

[head]

Early DT1, DT2, YZA. Later model DT AND MX'S 1973 ON WERE DIFFERENT. YZ'S STAYED WITH EARLIER MOTOR DESIGN. DT BARREL WOULD BE EARLIER THAN 1973. I THINK THE REED VALVE DT2MX BARREL THAT I USED WAS 1972 FROM MEMORY.

[asasin]

I have quite a selection of cooper parts .PM me if there is anything you need.