Andy wrote:It's not "having a go at Brollocks" day, don't worry, more of a return volley to Binka. I stand by what I said, as although not exactly the same issue (maybe because of setup like you say) but it is a similar symptom, so adding further to one of the previous threads I feel would have been valid.

My problem is I often have too much to say so tend to add it all in to one post when it's time to moderate a little. I'd rather make my point of view and feelings known outright, than snipe or whinge behind peoples backs! At least everyone knows where they stand then!

Hope there is some useful information or ideas here anyway, and best of luck.

There's a good point there - if you ask anyone who uses a php board and ask about searches, the answer is usually the same. Too many responses and too much rubbish.

Hence, what most people do is look down the first two or three pages and if there's nothing relevant, post a question.

The only bad question is an unasked question. The quality of the reply is where it can all fall down and Andy knows exactly what my take on that is.
I'd do anything for anyone provided it was a. legal and b. reasonable.
Just to be clear, I'm deffo not having a go at anyone, no need for that here as the majority are beyond that crudd.

Jacking up the barrels to give you more clearance in the squish is a really, really bad way to do this. It goes against every principal of 2 stroke tuning. Yes, it will change the port timings and squish. As noted by Howard Lees back in 1986 (PB) and echoed by just about every top stroker tuner, if you are jacking up the barrels you should really be doing this for 1 reason and that is because you screwed up the milling on the head or barrel deck. It is a common problem these days on old 350lc engines running a 375cc kit. The original 375cc conversion using DT175mx jugs required the barrel to be shortened and a mix and match of base gaskets were needed to take up bad machining or very small inaccuracies. This led to a lot of early engine deaths because people who didn't really appreciate how crittical it all is, had a go themselves and is the main reason why so few 375cc kits using the DT piston remain. They all blew up !
If I were looking at this problem I'd be looking at a meticulous check of the crank timing, ignition timing and carefully measure the chamber volume and squish. If all checked out ok when the maths and numbers were crunched then I'd leave the thin base gasket in there and use a detonation ring in the heads and use nothing but 4 star juice.
The 76rwhp YPVS runs a very tight squish, it has never misbehaved because the fuel is right for the ignition and compression inspite of my running some things that most people cringe at the idea of.



There's definately an issue with the lowe cylinder of NSR's curling up and dying.... closer analysis is needed me reckons.
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These aren't the droids you're looking for.