It's common on initial start-up, for one silencer to feel a little cooler than the other, but should soon even out. Unfortunately however, poor starting is very often due to crank seals. Is the bike a 1988 R2/4J Mk1, or a 1989 R5/6K Mk2? Use the Specifications section of the main site to quickly identify it.
NSRs can be notoriously difficult to start without a good, solid battery, so make sure it's fully charged, and no dead cells.
As Mark suggests, pull the carbs and check they are clean, and that there are no blockages in the slow jets. The carbs are very simple, and although it's a little tight on the MC18 with its narrow frame rails, are very easy to remove and come off as a complete assembly. If the inlet manifold is a bit tight, just warm it up with a hair drier or [carefully!] with a heat gun, to make the rubber a little more supple.
I'd also suggest popping the exhausts off, and having a look up the ports at the pistons. If you see any bad scoring, then it's possible that cylinder isn't firing.
I'm afraid there are plenty of horror stories about importers these days, and none I would trust personally. Too many trying to jump on the 2-stroke resurgence bandwagon, with little thought other than profit. We've had a number of bikes, motors, and cranks sent to us to make good over the last 12 months, that were from these so-called specialist importers!
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Andy.
NSR-WORLD.COM
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