Sandy, if you pull the heads, take a close look at the exhaust ports for carbon build-up. If there is much build up there, it'll have a big effect on performance. You'd have to pull the exhaust cover between the banks to get to them which is a bunch of bolts, and the ones in the center might be seized since that's the hottest part of the motor. I was able to pull that cover on my old 1975 V-4 years ago and clean out the ports. Even though I lost about 10-15 psi on before/after compression test due to all the carbon I scraped off the top of the pistons, I didn't lose a bit of WOT rpm, so I think the "bigger" ports compensated for the loss in compression! It was getting hard to start when cold before I sold it, and I think it might have been leaking reed valves that reduced crankcase compression. If you have that problem it might be worth looking at the reeds. Denny
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