This engine has the RS transmission, primaries, clutch etc all fitted. Quite a simple job to do it that way. But as you can see the RS cover doesn't have any casting for the kickstart so as this was a race engine (300) I welded on a plate to cover it up.

The mechanical waterpump has been removed and the case machined and welded up. This is running an electric waterpump. I've done this on 3 or 4 NSR's now.

If you want to fit the RS primaries but keep the NSR clutch, then I'm not sure of the exact method as never done it, but what I have done is keep the NSR helical primaries and fit the RS clutch to this. What I did was cut out the centre of the NSR basket (with the M7 bolt holes, and then cut out the middle of an RS basket after pulling the damper off. Then welded the NSR centre into the RS basket.

Trouble with this is that the RS and NSR main shafts are different lengths so I had to make up clutch lifter assy and push rod so that I could use the 3 ball system like the RS.

First attempt worked dimensionally, but I messed up when hardening the shaft and lifter. After first shakedown I could hear something "mechanical" so pulled it apart and the ends that I'd hardened had cracked. I hadn't tempered the part after hardening. I made another and this time tempered it after hardening, by looking on the net and finding a temper colour chart. Works like a charm.

Is it straight forward? No, not really. Is it worth it? Probably not much, but I did lighten all the stock components while I had it in pieces by thinning down the stock primary gears and also taking a bunch of weight off the stock NSR clutch assy.

I actually still have one of the NSR basket centres in the freezer. Found it the other day It's in the freezer as I made it a shrink fit into the RS basket to ensure a nice strong fit before welding.

Anyway, it looks cool so it must be worth doing.