Cool Head by Pro Design

[BKOLFO4]

If it was a long rod motor, do you think it would still have the stock pistons in it? Is that possible? If it is, would it still need smaller domes for a setup like that? I have a pretty good feeling from looking at the jetting that this bike was ridden at a higher altitude, thus the leaner jets and smaller domes. When I first got it, I replaced the plugs, and from the looks of them, it had not been running lean. If anything it was running rich (of curse I do not knwo the riding habits of the previous owner).

 

I know it was knocking hard; that is why I started looking into what domes it had. I almost did a compression test, but I was afraid (as already pointed out) that it might have smaller domes and they would be covering up a worn top end. I felt I needed to know what domes to know how to read the compression test.

 

I am planning to go ahead and rebuild the top end. The pistons are pretty darn lose in the cylinders. I can actually move them around freely in the cylinders and make them slap the wall with my finger.

 

Now my questions:

 

If I am going to rebuild the top end, should I measure the cylinders and see if I can go back with std. size, or should I just go ahead and start fresh at .020?

 

If I rebuild the top end, and it is the stock crank and rod, I will need 21-22cc domes for pump gas, correct?

 

Thanks!

Brian