HI there

I am currently rebuilding my nc23 engine after an off at anglesey which resulted in a broken selector barrel. I have fitted the new part no probs, just before putting crank cases together i decided to check crank and rods etc for wear or damage. This is where i forgot it has gear driven cams and not chain driven, as i rotated the crank it popped up out of the upper crank case halves. I managed to jostle it and get it back into position. This is where it dawned on me that it may have skipped a tooth and now be meshing in a different position than it should! which i presume will alter the valve timing relative to the crank. I decided to check valve clearences for peace of mind, but my bike is running total loss and has had the alternator rotor removed, but the rotor has the marks on to determin the position of the crank to enable you to check valve clearences. Will i have to buy a alternator rotor and put it on just so i can check the valve clearences or is there a dodge. I presume this is a common problem when checking valve clearences on total loss race bikes?
I would be grateful for any help given. Oh also does anyone no if an nc29 alternator rotor is same as nc23
cheers Rigs

We have plenty of used Tri Arm flywheels complete with their locking key and fixing bolt - £15 delivered. Paypal is quickest.

Give me a call daytime sometime and I can guide you how best to proceed.

Hi
When checking valve clearances,as long as the cam lobe is pionnting away from the valve bucket ie 180 degrees from holding the valve open you can check that valve clearance.So you dont need a flywheel to do cearances.
Hope that helps

piston wrote:Hi
When checking valve clearances,as long as the cam lobe is pionnting away from the valve bucket ie 180 degrees from holding the valve open you can check that valve clearance.So you dont need a flywheel to do cearances.

Yes you can do the valve clearances that way, but the timing can still be out!

to set the cams - take out the spark plug out of cylinder 1. ie the one furthest left (while sitting on the bike) . stick a screwdriver etc down the plug hole, turn the engine over with a socket on the end of the crank bolt until the screwdriver reaches its highest point. this will be TDC which is marked T on the flywheel. refer to the manual about positioning the cams so that the lines face the right way. IN should face to the left and EX should face right when looking from the right hand side of the engine (from memory).

to check valve clearances - as long as the cam lobe is facing away from the bucket, doesn't matter on stroke or anything else.

cheers i ll give it ago.

rigsby

Hi Dude, sorry didnt read the post correctly. I only looked at the title for the post & didnt realise you needed the timing explaining to . Anyway I see you are now sorted out so all good. Thats what happens when you get up early for work & are still half asleep lol.