Gear Box help needed

[cbranni]

Rugby match..........................

[Ozmadman]

Still struggling with this.Does anyone know which gear selector fork goes on first i.e nearest to the rear of the gear box. The selectors are distinctive with one being a bronze colour. I cant determine which is which from any of the pictures in the parts book or the mechanics magazine article.
Thanks

Have you got the box out or are you trying to do it in situ?. My selector forks looked similar and same colour so wondering why one of yours is a bronze colour??
If you are building the box off the bike it doesn't matter as far as I can see as you can move the shafts around and fit them in either one first. Put the selector forks in place making sure both holes line up with each other and with the hole in the casing which takes the rod and with the pegs located in the selector gate grooves and THEN PUT THE SELECTOR FORK ROD IN AFTERWARDS. if you have the rod in already and are trying to do the selector forks that way then unscrew it and do the above. The forks will only fit like this if they are in the correct way so the wrong fork can't be put on the wrong set of gears.
Paul

[Merlin]

Rugby match..........................

[Rangy65]

Thanks Paul, i have the box on the bench. I am going to wait until Colin posts some pictures because i can,t seem to work out what i am doing wrong. I am trying to fit the gears,shaft and selectors as one unit as in the motorcycle mechanic's mag article. i will try your method. I the mean time here is a close up of my selector forks not sure if they are correct though.

IMG_0328a.jpg

Cheers

[Malleon]

Rugby match..........................

Swing low, you sweet, sweet chariot !

Oh, what a lovely Triple Crown. A Triple triumph rather than a Triumph triple, gloat, gloat.....

[Ozmadman]

They seem to look ok when compared to pictures of mine, here are a couple of pics but cropped from a bigger picture of all my gearbox internals so they are not brilliant. There's no need to try to put it all together in your hands and then try to assemble it in one bit in my opinion.

I build the boxes from the opposite end as shown in that article as I find it a lot easier. Start with the thin plate(the one with the selector gate and rod in it) on the workbench, I use a workmate so the rod can hang down underneath and the heavy gate is facing up(see picture). Fix the main shaft in the small bearing tightening the nut, I would also loctite this nut as they are prone to coming loose. Attach the kick start shaft ( and bits, spring etc)in the large bronze bush in the same casing and tension the ratchet so you have a healthy return on the kickstart when you let go of the lever (don't forget the spring behind the ratchet).

Now you have the main shaft sticking up and then the lay shaft(with the first gear on it) can be inserted into the flanged bush in the kickstart shaft . You can start building up the gears. Just find out what gears etc go on which shaft and build each shaft in place moving between shafts until all the gears are on(make sure the first gear on the layshaft faces ratchet teeth downwards to engage with the teeth on the kick start shaft when the kickstart is pushed down as the gear can be put on either way) Now rest the selector forks in place so that the holes line up and with the protrusions engaged in the selector gate grooves( if you can't do this then the selector forks need swopping round, they will only fit one way).

Now the output gear/oil seal and oil seal sleeve...I fix all this it into the casing/bearing at this point by putting it together, putting the sprocket on and then hand tightening the large nut(LH thread), don't forget the tab washer, . I then clamp the sprocket very tight in the jaws of the workmate so the rest of the gear and casing is hanging below, this allows me to really tighten up the nut without putting any strain on the output bearing. Then screw the selector fork rod into the casing as well. Now you have a built up box with all the gears on their relevant shafts and a casing with the output gear attached to it. Once all gasketed up, lower the casing with the output gear on it over the top of the shaft/gears and look to get the end of the mainshaft in the output gear at the same time lining up the end of the layshaft so it can go into the bush in the casing which is next to the output gear and finally so that the end of the selector rod goes through the selector fork holes and into the small hole in the casing as well, its a bit fiddly but you can use the casing edges and dowels as guides and also twiddle the the selector rod to slightly move the selector gate as well. Once it is all lined up it will just drop into place, and done!! Once you are happy and have tightened up the 6 screws THEN you can screw the sleeve,spring and plunger that tensions the gate for gear selection into the casing and, even though the sprocket is already on, there is enough room to use a spanner to tighten it up properly. JUST MAKE SURE THAT YOU DO THIS WITH THE BOX ON ITS SIDE AS YOU DON'T WANT THE PLUNGER SLIDING OUT OF THE SLEEVE AND DROPPING INTO THE BOX BEFORE YOU TIGHTEN THE SLEEVE UP, otherwise you will have to take it all apart and do it again. The box is now built and you just need to finish off by building up the gear change mechanism and clutch lever housing etc into the outer casing etc etc etc, presuming you are ok with that bit?

Paul

[Rangy65]

Blooming brilliant Paul!! I hadn't even thought of building it up as you have described. I am away with work all week so will be having another go at the week end.

Top man!!

[Ozmadman]

Blooming brilliant Paul!! I hadn't even thought of building it up as you have described. I am away with work all week so will be having another go at the week end.
Top man!!

No worries, didn't have any instructions when I built the box for the first time and after a long think It made sense to me to do it this way. It's not that difficult dropping the output casing down over the shafts and actually once you have done it few times it's quite easy. Let us know how you get on
Paul

[Janet]

Blooming brilliant Paul!! I hadn't even thought of building it up as you have described. I am away with work all week so will be having another go at the week end.
Top man!!

Let us know how you get on
Paul

Is he still struggling with it? Did it work? Are Paul's instructions clear, concise, accurate and worth putting into Technical Articles?

[clive]

Janet my guess is he sold the bike if he still hasn't sorted the gearbox 10 months later.