Does anyone have a diagram of a 340 6 speed gearbox please.

Split it several weeks ago, put it back together today and it seemed to find all the gears when manually using the shifting drum. Put the other casing on ( without the crank ) inserted the gear selector shaft and shifting trigger mechanism and it wouldn't engage a gear.

Done a couple of 5 speed boxes before no problem.

Serves me right for not doing it all at once.

A diagram would greatly assist although I bet they're like hens teeth.

Its either a selector in the wrong sequence although I don't think so or the shifting trigger mech, but again they look ok.

Something to ponder over gentlemen.

Thanks in advance as always .

Edited May 16, 20179 yr by chappo

There isn't a parts diagram for the 340, as far as I know

If you can go through the gears successfully with the drum then the gears and selectors are assembled correctly

With the crankcases still assembled, remove the selector mechanism and see if the drum will still operate the gears now that everything is tightened up, as opposed to operating it in just the one crankcase half  - it can be done.  If so the problem is with the selector mechanism which obviously worked fine before stripping.

Have you got the selector pawls the right way around so that the are engaging properly with the drum, they are handed if I remember correctly as they have a smooth and sharp leading edge

Have you got the spacer / shim on the end of the layshaft. If missing it wouldn't cause a problem when shifting through the gears in just the one half, but may do when all bolted together

Back in the day when I worked for the Bultaco importer in Ireland, we never received a parts manual for the 199B. We used a generic 199 manual for ordering parts. No technical bulletins or spec sheets were ever received either. Unfortunately this was one of the many side effects of the pure chaos that was going on in the factory for 79 to 83.

Edited May 17, 20179 yr by model80

Thanks Woody & Model80.

Tried to load an image of the gearbox and selector pauls but it's saying the image is to large. I've never had a problem loading images before.

I was just wondering, did you put a centre case gasket in before you tightened the cases up? I remember when I put my 199B back together, with the motor on the bench I was not convinced I had all the gears, but once it was installed in the bike with all the accessories, clutch, chain & sprocket etc was I able to find all the gears easily and it shifts perfectly, but as I said on the bench it didn't feel as positive as the 5 speeds.

Cheers Greg

 

 

 

 

 

 

 

 

 

 

 

 

Edited May 17, 20179 yr by sherpa325
spelling

Thanks Greg, good point, no it was casing to casing, I'll give it a try.

Ok guys, looks like I've got it sorted.

But thanks goes to Woody and Bondy who identified the issue.

The pawls in the selector mechanism came out as I disassembled the engine, without looking i put them back in the mechanism as I would a five speed one. But on closer examination they have a step in one side which needs to face outwards.

The gearbox selects all the gears now but some are stiff, but as Sherpa325 says once it's all torqued up , ancillaries fitted and filled with oil I'm sure it'll be fine.

Upward and onward.

Glad it's sorted  -  they're always stiff when running through on the bench, but as long as they all select they'll be fine when all assembled and in the bike

Got her finished today and she runs like it just came out of the Factory gates.

Saying that only been up and down the drive, but all seems good.

Hopefully out on her this Saturday at a Red Rose event.

It will need running in there's always something to Ajust

Yes spotted deliberate mistake, the Red Rose event is actually on Sunday not Saturday

Sherpa325, you were right, all that worry when she was on the bench.

Got her to the trial, rode her round the field for 10 mins and it felt just right.

All gears selected perfectly and the clutch was fine.

Just decided to upgrade the Bing for a Mikuni.

Relief?

Good to hear, I prefer the keihin though over the mikuni however

I have a oko on my 199A runs sweet

 

 

12 minutes ago, bondy said:

I have a oko on my 199A runs sweet

 

 

What size OKO ?