chappo Posted May 16, 2017 Report Share Posted May 16, 2017 (edited) 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, 2017 by chappo Quote Link to comment Share on other sites More sharing options...
woody Posted May 16, 2017 Report Share Posted May 16, 2017 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 Quote Link to comment Share on other sites More sharing options...
model80 Posted May 17, 2017 Report Share Posted May 17, 2017 (edited) 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, 2017 by model80 1 Quote Link to comment Share on other sites More sharing options...
chappo Posted May 17, 2017 Author Report Share Posted May 17, 2017 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. Quote Link to comment Share on other sites More sharing options...
sherpa325 Posted May 17, 2017 Report Share Posted May 17, 2017 (edited) 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, 2017 by sherpa325 spelling 1 Quote Link to comment Share on other sites More sharing options...
chappo Posted May 17, 2017 Author Report Share Posted May 17, 2017 Thanks Greg, good point, no it was casing to casing, I'll give it a try. Quote Link to comment Share on other sites More sharing options...
chappo Posted May 19, 2017 Author Report Share Posted May 19, 2017 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. 2 Quote Link to comment Share on other sites More sharing options...
woody Posted May 20, 2017 Report Share Posted May 20, 2017 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 1 Quote Link to comment Share on other sites More sharing options...
chappo Posted May 22, 2017 Author Report Share Posted May 22, 2017 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. 4 Quote Link to comment Share on other sites More sharing options...
bondy Posted May 24, 2017 Report Share Posted May 24, 2017 It will need running in there's always something to Ajust Quote Link to comment Share on other sites More sharing options...
chappo Posted May 25, 2017 Author Report Share Posted May 25, 2017 Yes spotted deliberate mistake, the Red Rose event is actually on Sunday not Saturday Quote Link to comment Share on other sites More sharing options...
chappo Posted May 30, 2017 Author Report Share Posted May 30, 2017 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? 2 Quote Link to comment Share on other sites More sharing options...
sherpa325 Posted May 31, 2017 Report Share Posted May 31, 2017 Good to hear, I prefer the keihin though over the mikuni however Quote Link to comment Share on other sites More sharing options...
bondy Posted May 31, 2017 Report Share Posted May 31, 2017 I have a oko on my 199A runs sweet Quote Link to comment Share on other sites More sharing options...
markg Posted May 31, 2017 Report Share Posted May 31, 2017 12 minutes ago, bondy said: I have a oko on my 199A runs sweet What size OKO ? Quote Link to comment Share on other sites More sharing options...
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