Is that the Z or H spec? Can get bt90 in oz but is not the design now a bit long in the tooth. Options for 18" rear here are limited to a few sport/touring types although they offer an acceptable level of performance with good mileage. Alpha 13 & 14 and the Metzeler RR or another sticky tyres are not imported as the market is too small.

How about the Hawk GT rear wheel ? Would that fit my 1990 NC30 ? I think that's 4.5 inch.

The Hawk GT wheel is the same rim size as the NC35 but the hub dimensions are different so it won`t fit the NC30/35 axle.

I`ll qualify that by saying I have seen it done but it involved hogging lumps out of the wheel hub with an angle grinder and the final result had no proper drive pin location.

Rick

Thanks for the reply, @RickOliver.

So, what's the last word? Can I fit an rc30 5.50 rim on the nc 30 swing with chain spacer? And does the 170/60/18 turn without hitting the arm?