The rebirth of Lazarus

[mickwinf]

a bit of progress

[Oddjob]

Still not keen on that front stud near the camchain tunnel Mick, will it come out?

[mickwinf]

i have not tried to remove it Ken, should I?

[Oddjob]

You can try but if it doesn't move don't force it. A really good stud extractor is generally essential, the 2 nut trick doesn't normally work.

I may have a decent stud lying around.

[mickwinf]

This afternoon i started to re-assemble the gearchange mechanism, and to check if it changes properly. It does not. It seemed to change up ok but not down again, i have checked everything i can think of but am worried I may have done something wrong inside the gearbox but was very careful so not sure what i might have done.

[Oddjob]

Remove the gearchange shaft, get a screwdriver and fit it into the screw on the end of the gearchange drum. Whilst rotating the clutch shaft turn the screwdriver and see if it goes up and down ok using just that method. If it does, it's either the pins in the drum which the gearchange shaft engages onto or the shaft itself. If it doesn't it's not the gearchange shaft so you can eliminate that.

Did you assemble the engine in the top case or the bottom case?

[Bryanj]

I cant think of anything internal that would allow upchange but not down change, try rotating both shaft when trying, especially 5th down to 2nd

[mickwinf]

will have a look tomorrow. I assembled it in the upper crankcase

[Oddjob]

Bit late to say this Mick but ALWAYS do a dry run changing gears when it's still in the top case, do the screwdriver trick and you can not only make sure all the gears select but also you can watch the gears engaging and spot any problems.

[mickwinf]

Well i had a fiddle with things and it seems to work ok now, i think i was not spinning the shafts enough. So i thought i would assemble the clutch, and all went well until the final bolt sheared off! Will sort that another day, Lazarus will live!

[Oddjob]

Bolt in the clutch or in the case?

[mickwinf]

Ken it was one of the 4 bolts that go on the springs, so in the clutch centre, wasn't even putting any force on it.

[Oddjob]

Anything left sticking out?

I have some of those bolts spare I think, measure one and I'll see if the 550 ones are the same.

[mickwinf]

The sheared bolt was easy to sort as the hole it fits in is open both ends so i drilled into it from behind and it wound itself out. I have been fretting about the gearbox it did not seem right to me, so convinced myself to strip it back down. I have acquired a spare gearbox so compared the two and against the manual. it seemed i had one of the thrust washers wrong, not sure how much it would affect things but given me a bit of peace of mind. I also changed a couple of bits as the spares were in better nick. One more question for you Ken, remember the gear with the top hat bush? i am a bit worried if it is in the correct way, is it as per your photo on page 4 of this thread? I am also going to double check the selectors to make sure they are correct. My new rebored barrels and pistons are ready at triggers so slowly but surely it will rise again.

[Oddjob]

Yeah top hat goes in on the flange side. Correction, it's the other side that has the rim of the hat so to speak.