Basic gearbox/linkage question (915)

[Magnum]

Hi all

I do not have much experience with the 915, however, I'm struggling a little shifting into second gear. As much as I've adjusted the linkage, replaced linkage bushings, replaced gearbox oil and the transmission mount/engine bushings it has improved but still feels "notchy" into 2nd, especially more so when cold. But it doesn't grind.

To me, with my inexperience, the "notchiness" feels like a linkage/selection issue and I should add that I do have the Porsche short shift kit and solid PSJ joint which no doubt makes adjustment more critical.

HOWEVER if I match the revs on the downward shifts it changes beautifully - that implies that it could be the syncro ring which I understand to be a weak point. Others gears are absolutely fine - is 2nd gear syncro likely/known to wear far ahead of others?

Any thoughts out there?

[911hillclimber]

I have 2 boxes, both rebuilt and both are like yours!
The one improves with heat on a drive.
Suggest a call to Mike Bainbrige in the Lake District.

With a tight modified gear lever assembly ( I have this too) adjustment is very critical.
My other race car box has no such thing and is still hard at times.
Does double de clutching help when cold?

[Gary71]

If it’s not been done it will be worn synchro rings. Change them before it starts to crunch otherwise you’ll need a new 2nd gear with sharp dog teeth and a new selector ring.

My wallet speaks from experience

[fetuhoe]

The short shift isn't really your friend as they can be a pain if the reverse lock out is 'sticky' or there is wear in the pins.

I would still tend to blame the synchro but would also be inclined to change the dog ring at the same time.