Regarding the third gear on main shaft, I had exactly the same problem, and removed a bit of the inner bush. The problem comes from the shaft itself (mine comes from the club spares) which has been machined a bit to much thus allowing the small adjacent gear to slide too far and block it.

Regards

It is okay for me !

Will recheck this !
Box is opened, dogs are a bit worn on some gears. I have a very decent GB39K55 gearbox, which corresponding gears have the same number of teeth, and selector forks are one piece, very good shape. Would it be a problem to mix parts ? ( my forks are the 2 pieces type).

Regards.

Yep it will need reopening… seems like it’s a never ending task.

The gearbox is a GB7 D52.

Cheers

Not really, now I have a problem with the gearbox itself : 2d gear won’t engage properly, it keeps disengaging when under load.
I have changed the index plunger, no change…

Hi, it’s been a long time, but I finally managed to take some measurements :
- the gearbox mainshaft has a runout of around 1/10 mm
- with a remanufactured sleeve (from India it seems), runout is 3/10 mm
- with a correct second hand sleeve, runout is kept at 1/10 mm

End of story ?

Could, by any chance, this compression ratio blowing ordinary gasket be cured by copper gaskets ?

Regards

Hi, I am away from the bike right now, but I’ll make some measurements next week. I think eccentricity could be around 1 mm. Paul, yes this is the sleeve which sits between clutch center and shaft. It is brand new from Draganfly, but you never know. I will check the chain also, as I can’t remember e...

Hello, After a thought, I don’t think it is the clutch wheel. Conditions are : gearbox in neutral, clutch not moving, turning the rear wheel. The mainshaft turns with its sleeve within the clutch center and makes the clutch wheel/basket/center move eccentrically, as if the shaft was bent, but it is ...

Chain tension variation can’t be good, especially considering this is only a simplex. Could the clutch wheel (refab) be the problem ?