430 squish

Hello all
I just got done measuring the the squish band on my 82 XC 430 with a 2nd over Wisco piston and found out that is .087 or 2.2mm
My question is it too much seems to run and start all right
Thanks
After removing the head and have the solder in the right way it now measures .083 still seems high from I have been reading

Happy to help. That is large. The hard part is that Husky was all over the map with this dimension. They even had some '81 430's where the piston was contacting the head. They released a factory service bulletin about this. Obviously, you have a combo that is on the other end of this spectrum.

Then, they played with exhaust port height a bit, with the CR generally running about 1mm higher than the WR/XC. So I don't like to randomly say "run a thinner base gasket." It's much more correct if you can measure a few things and identify WHY it's .087". My answer is, unfortunately, going to be long!

First, I'll say that these motors run well. You would likely find it very satisfying just the way it is. Of course... it would run even better if you got that dimension cleaned up. If you want to tighten this up...

I'd first verify three things:

1. The thickness of the base gasket you currently have. Husky only lists one part number, but they made a thick one, at nearly .060", and a thinner one, at .048". I haven't found an .060" for years. It may have been a short run to fix that 81 until they fixed it more permanently. But worth checking. Both are a really nice quality re-usable metal/fiber mesh composition.

2. Which cylinder head you have. Some have the squish band "level with" the cylinder mating surface. Some have the squish band recessed into the head.

3. The alignment of the piston edge and the bottom of the transfer ports at BDC.

One of these is likely to point you directly to where you should start. If you want to do those things then get back to me, I can suggest where to go next. IF (IF) you do need a thinner base gasket, they are available from Cometic. I contacted them several years ago and they were willing to reproduce them for us in several thicknesses!

Do you want to look at these things and get back to me?

Dave

Not sure if this applies to your bike, you'll have to compare your serial number with the numbers mentioned in this service bulletin.

That's the one! Thanks Crash.