81 LML 150 originally came from Dunedin.
It didn’t run but the rego was on hold and it was a good price. It had a PX engine in it and some aftermarket performance parts.
The frame was in good condition and had good tyres and shocks.
The engine had a Malossi 210 with a Malossi reed valve, 30mm DellOrto, a lighter Pinasco flywheel and a Polini box exhaust. The previous owner had the engine set up by someone else but couldn’t get it to run reliably so offered it to me.
Before stripping the engine I did a leakdown test which confirmed there were 2 air leaks – one in the crankcase and one in the cylinder base gasket. This would make it very hard to tune.
As it turned out there was also an issue with the Pinasco flywheel and the LML ignition system. This would also make it very hard to tune.
Once the engine had been stripped there were a couple of other things to sort out and it was downhill from there. The stock 57mm crank had been welded at some stage and was out of alignment which may have caused the main crankshaft bearing and housing to wear. The main bearing housing had been damaged and this allowed the bearing to move and spin within the housing. Someone had tried fixing this, using an after market bearing retainer for PX cases, however one of the case threads for the 2 bolts used was stripped and barely doing its job.
The crankshaft had a crank seal sized ring on the cheek, that shouldn’t be touching the seal, which meant the movement in the crankshaft was also going to be a problem.
I sent the main bearing side case to a friend in wellington who got the case machined and a bearing insert installed. Its very much like the old VBB cases that have the copper type outer ring in the bearing housing. After installing a new bearing and seal set, a Mazzy 60mm crankshaft, a standard PX Flywheel and a new stator, the engine is running very well.
The Malossi reed valve is very noisy and the constant “drone” at higher speeds is a little annoying so next on the list are better reeds and maybe another manifold.