Author Topic: Ossa gearbox  (Read 2267 times)


  • Newbie
  • *
  • Posts: 1
    • View Profile
Ossa gearbox
« on: March 22, 2014, 08:41:21 PM »
Hi everyone, my first post and hoping someone can help.
I've got a 2012 factory that has had gearbox problems.
Box is back from dealers having been repaired but I can't get it to fit properly.
For some reason when the 5 bolts are tightened up it stops the selector from moving.
If I leave the bolts slack it changes fine, usual silky smooth. But tighten them and it goes all tight.
Also when in place the sprocket shaft doesn't seem to be through enough to fit the circlip.
Hoping that I'm missing something and I don't have to send it away for more repairs.


  • Full Member
  • ***
  • Posts: 135
    • View Profile
Re: Ossa gearbox
« Reply #1 on: March 22, 2014, 08:46:26 PM »
Welcome !

  I gave a couple ideas on the other forum, but BigBadDon here has had his out.
Hopefully he will have some ideas.

2014 OSSA Explorer


  • Jr. Member
  • **
  • Posts: 65
    • View Profile
Re: Ossa gearbox
« Reply #2 on: March 27, 2014, 04:53:49 AM »
Hey Mac,  I found the sprocket cirlip to be a tight fit, but managed to get it all together and has worked fine.

As for the shifter not moving.  One thought is the shift return spring has slipped up and forced the shifter assembly up.  Then when you tighten the tranny in place, it has an extra 2-3mm on the shift drum.

Any chance you can take a picture of the shift shaft assembly on the tranny and post it?

I have posted what mine looks like with a point to the spring.  "A" show the shift drum nicely sitting close to the tranny plate. "B" points to the shift return spring which can pop off the shift shaft assembly and force the drum up 2-3mm.


  • Newbie
  • *
  • Posts: 4
    • View Profile
Re: Ossa gearbox
« Reply #3 on: September 22, 2014, 08:33:59 AM »
Has to be in gear when removing and replacing.