cr500 piston drilling

[gassergrant]

Hi just out of interest I am having to rebuild my big5 as it seized up do to the exhaust port bridge not being relived but ive seen on Wesco web about drilling lube holes which looks like a good idea.
has anyone done this before and can anyone ell if this is in mills or inch please

http://www.wiseco.com/PDFs/Manuals/MSeries.pdf

thanks grant

[Diggs345]

Originally Posted by gassergrant

Hi just out of interest I am having to rebuild my big5 as it seized up do to the exhaust port bridge not being relived but ive seen on Wesco web about drilling lube holes which looks like a good idea.
has anyone done this before and can anyone ell if this is in mills or inch please

http://www.wiseco.com/PDFs/Manuals/MSeries.pdf

thanks grant

Join the cr500 forum , loads of info in there , I built a 500 into a crf 250 frame back then , was nice but just wore me down .

[rosco]

That would be in inches. Use to do a lot of them on the old cylinders with a steel sleeve. Wiseco pistons seem to expand a little more than the stock pistons do. I would drill the holes like they say and I would still relieve the ex. bridge a little. You want to make sure you let them big bore 2 strokes warm up good before you take off riding. Its real easy to cold seize them suckers.

[gassergrant]

cool cheers for the info lads got to work it in mils now lol