Zeus wrote:
Well just to update this post, I’ve finally got the cylinder back and it’s a great job they have done. It’s like new!
I chucked it back together and it’s running again (obviously I rebuilt both cylinders), let’s see if it lasts longer than 2000 miles this time.

Great to hear you're up and running again.

I'm a bit late to this one, but here goes anyway, and I apologise in advance... 😬😬😬

Did you tell Lancourts not to face the top of the barrel under any circumstances? The NSR is extremely susceptible to compression changes. If they skimmed it AT ALL I strongly advise you to measure both barrels and fit the shortest on the top. The lower cylinder is already prone to detonation, and increasing the compression will just make it worse.

If you don't have the measurements for the deck heights, and aren't inclined to pull it apart again to check, just ensure you keep a really keen eye on the jetting/spark plugs; particularly on the lower cylinder. Going a tad richer can help overcome very minor detonation, and use the best (highest octane) fuel you can get. If the barrel measures short, depending on the model (R or SE/SP) you really should consider experimenting with 0.6mm HRC base gaskets and alternative heads to bring it back in line for longevity.
_________________
Andy.
NSR-WORLD.COM

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