Modern Vespa

I am begining a rebuild on a 1967 125 GT 2-Port Engine. I plan to add the 177 Pinasco kit. The gears all have a notch at the inside corner. The outside corners seem square. Is this from wear, or was this ground intentionally by a previous owner? Something to be concerned about? Do these need replacement?

Thanks for your help.

Those ramps are there from the factory.

The notches look a bit suspect.

I'm guessing someone installed a hardened crimaz cruciform which possibly made those suspect notches.

Quote from interwebs:
The Cruciforms from CRIMAZ are made of steel (16NCD12) which has been hardened under vacuum. The surface hardness is certified with a hardness of HRC 58-60.
The type of milling at the ends of the cross is designed to protect gears and transmission parts. The Cruciform is slightly larger than the original. Therefore, minor reworking may be necessary during assembly

'Cruciform is larger' and 'reworking' are the key words that stood out to me.

Thank you for the input. Would you replace these if it was yours?

Thanks,
Tom

I would replace, if it was mine. Those chips/gouges speak to rough shifting; or could be from a 'performance' cruciform as said above. Chips in the gear could lead to cracks then breakage.

I have "performance" shift crosses (including DRT) in all my engines. Never have i found abnormal wear on any of my loose gears. It almost seems like the inside diameter of the loose gear could be getting worn (as in larger i.d.), or perhaps the outside diameter of the lay shaft is getting smaller from being worn down?

Gears are so expensive, and I'm not sure I see the harm in that weird modification they did - unless it propagates a crack or something.

That's a hard call on keeping those. If there is a danger in locking up a gearbox though, it seems like replacement would be better. Getting thrown from the bike doesn't sound appealing to me.

I just don't know how you'd assess the relative risk.

I wouldn't hesitate to replace that gear if it was in my scoot. It's apart anyways. One less thing to worry about out on the road.

to be honest, what I'd really do is put it together, worry about it, then tear it back apart and replace all those gears.

This makes sense. If the gears are chattering and knocking around loose on the shaft. I'll admit I only ever use Piaggio cruciforms, and have no IRL experience with other brands. Although I will be using a BGM cross in my current P2 build, as that is all that was available when purchasing parts

Don't the early model 2 ports have the 2 part bearing on the flyside of the cases? With the annoying cage/ needles? That could explain wobbling on the axle/ wear.

Might check the bearings for any missing needles/ ball bearings, notchy spots etc.

That's the spirit!

I'm getting better - I'd at least tear it back apart before I put it in the bike now, instead of waiting for later.

They do