I am putting the final touches to a James  am building got it started and there was a intermitant noise comming from the engine and think  have found the problem I have fitted the smaller front sprocket and the chain is slightly rubbing the front crank case with the seal I brought all the parts from villiers services and they said I need to use a die grinder to make it fit thats OK, and I mention the play on the clutch hub shaft (9E conversion on 8E gbox) and they told me there is an adjuster behind the gearbox casing where the push rod goes through but cannot find any details apart from the play should be 0.02" just need an idea how to do it also I have to align the front sprocket with the clutch hub, anybody else already done this? Just wanted some advice while I am waiting for the gaskets to arrive.

google 2015 someboby else asking about 8e 3 speed gearbox mainshaft end float I got 3 speed gearbox look weekend think its taken out by clutch adjustment with the adjuster as for engine sprocket tap the oil seal bit more in take bit crankcase or old primary chain let wear its a long time I am building 8e in time how about fliting 9e 4 speed gearbox I seen it never gone down that road  

Yes I have thought about 4 speed box and have a eye open for one but I have been told that the 3 speed gearbox is fine on the road. I will look at the seal, thanks for the reply 

I use the 3 speed box for trials it’s all you will need. Mine came with a wide ratio set up so 1st and 2nd in the sections then a big step to 3rd for the road it works extremely well plus it’s a bit slimmer than the 4 speed. A superb little engine and box.