Unknown Plug in Gearbox

[Craig]

Hi

Wonder if group could advise me what is this "plug" in the bottom of the gearbox. Have a small oil leak around it which i want to sort out.
No reference to it in the workshop manual.

Cheers

[beezermacc]

This is the plug / sleeve which houses the camplate plunger and spring. You can remove it, along with the plunger and spring, without upsetting anything so you could put a fibre washer or PTFE tape on the threads. When you replace it you need to make sure there is adequate pressure on the plunger to hold the camplate in gear. If the bike's gearbox works OK now you should refit the unit with the same tension as you have currently.

[duTch]

 

This is the plug / sleeve which houses the camplate plunger and spring. You can remove it, along with the plunger and spring, without upsetting anything so you could put a fibre washer or PTFE tape on the threads. When you replace it you need to make sure there is adequate pressure on the plunger to hold the camplate in gear. If the bike's gearbox works OK now you should refit the unit with the same tension as you have currently.

 ** Probably stating the obvious, but make sure you drain the oil first, otherwise you'll be upset

[muskrat]

G'day Craig.
And usually done up so two threads are showing, meaning yours might be a bit tighter than required. It's a suck and see type thing. Too tight and gear selection can be stiff, too lose and she'll jump out or miss gears.
Cheers

[u28909z]

A word of warning if you use PTFE tape. I once split a pre unit Triumph gear casing because I put too much tape around the threads of the detent plunger, there was a sickening crack as I tightened it. Alloy castings are not good with too much tension.

[jachenbach]

Don't know if it's available in other parts of the world, but the best thing I've found (or actually, was shown by an old-time Honda mechanic) for sealing threaded fittings is called Rectorseal. It's actually for sealing pipe threads. A very thick paste. Works great on drain plugs, especiallly when they're old, worn, and possibly getting a bit loose fitting. Far better oil seal than teflon tape, in my experience, and doesn't add tension when tightening.

[Greybeard]

This stuff?
http://www.allpumpsdirect.co.uk/Rectorseal-5-Pipe-Thread-Joint-Sealant

[muskrat]

I managed to stop the choking fit. Sounds like something you'd find in a gay bar or moped shop or to fix the plumbers crack  .
I use https://www.permatex.com/products/thread-compounds/thread-sealants/permatex-high-performance-thread-sealant/
Cheers

[chaterlea25]

Hi,

Rectorseal

Something to quieten the Vicar????

John

[cznorbert]

Hi Gentlemens,

unfortunately I had to repair the gearbox because it got stuck in 4th gear

it was fixed but i don't know why it happened, i didn't see any wear on the gear shift mechanism

I'm writing because of that, how is the shaft marked G fixed? (pls. see attachment)

I pulled it free through the center cover, in my opinion it could be stuck in the shift mechanism

[cznorbert]

Also, how do you adjust the lower fixing pin?

I saw 5 threads , is it not too tight?

Could it have caused the gearbox to stick?

thanks for the help

[Swarfcut]

 Norbert, that shaft is fixed to the main casing by a small grubscrew, look under the dirt next to the sprocket.  Very awkward with the gearbox in place, it is underneath! Better done with gearbox removed, so leave alone if you can. The gear selector forks should slide easily along this shaft. With the grubscrew removed, the shaft will pull out.  Check  that the shaft is true, and not bowed or bent. When reassembling, leave  the grubscrew to last to avoid damaging the casting. All mentioned in previous gearbox posts.

 The plunger, spring housing  (I think you called this the lower fixing pin) and spring simply unscrew, and with just a couple of the housing threads showing  below the locknut, reassembled into the gearbox should be a good starting point for adjustment. Too loose...jumps out of gear/won't change gear. Too tight... hard to change gear. 5 Threads showing is a bit too loose, screwing the housing into the gearbox puts more tension on the plunger spring. So, Yes, too loose could have been the problem.

 This adjustment is critical as some spring tension is needed to enable the plunger to rotate the camplate, more influential in down changes, as well as hold the  plunger against the camplate notches and keep the gear selected, without being too tight, which makes the camplate harder to move.

 Swarfy.

 

[cznorbert]

Dear Swarfy,

thanks for the quick reply

real help, as always