Modern Vespa

so, to preface. I *know* when shit is wore the fuck out or totally waxed. and I *know* that anything tuned best be right and true.

but, with a low power application, say a VBB or VBC 2-port how much chicanery is allowable on the gears? obviously chips and cracks is a no go, but what about some kinda sorta beat lands? eh? maybe? slam a cross in and know you're going back sooner rather than later? shim it tight and ship it?

any and all discourse is welcomed and noted.

I think you're pretty much spot on, especially for a low power motor.

So long as the cruciform is okay, the gears are properly shimmed, and the selector box isn't a mess, I think the odds of popping out of gear are pretty low. Those of us around here tend to take a "just replace it" attitude because parts are cheap relative to our time. That's not the case in most places, and so they get a lot more use out of parts than we do.

Things we look at and say, "Better to replace it while the cases are split," are considered "Grade A -- Perfect Repair" in a lot of places.

Think about the beat-to-hell, completely worn out motors out there hauling folks around every day. Most of them don't even have one, much less all three of the cruciform, shims, and selector "in spec" on their setups.

I worked in a scooter shop at one point, and if there was any noticeable wear at all, they would replace them.

But only ever saw that with first and second, bc they get all the abuse.

If they're something hard to find, I'm sure you could just re-machine them. There's nothing that needs to be precise about the internal gap. But since new ones are in the $60 range, it's always been easier to replace.

I would want them perfect. If you're nice to an engine, it can go decades without needing to be cracked open, and who knows how long these parts will be available.

full disclosure, I'm:
A- being a cheap ass
B- lazy, I don't want to go in again
C- it's for dr. mrs. the greasy

it's 2 port 150, so I'm thinking fresh cross and shim it tight. new box and call it.

I'm sure she'll get bored with no power having putt putt and want something else before any of it becomes a problem. or, at least that's my hope and to buy me time.

but much to y'all, it used to be ANY wear was baby with the bath water. I can understand chips, or fully rounded out, but just a fair amount and let it ride?

but ALWAYS a new cross.

I think your plan is solid.

I don't know Dr. The Mrs., but it sounds like she's not looking for a fire breather (yet), and if she eventually is, you're going to need three ports anyway, so just kick that can down the road until then.

I've replaced a shifting cross with worn gears, and it worked fine.

The cross is half of it. I think it probably the worn gears make the cross wear faster, but it will probably work for a long time if it's not a commuter bike.

I imagine with that displacement and a fresh cross, it could be even easier to shift(?). Kinda pre-chamfered like 4th is.

thank you all for not shaming my cheapness or laziness. much appreciated.

It's a fine line between laziness and efficiency.

You can always do it in the future.

I feel very seen right now.

hoisted by my own pe-tard, as it were.

Do the shifting cross challenge:
1 shifting cross
1 case gasket
1 hour

on a p-series? sure. on a smallie with a two piece fly side? yeah.

anything else? nah, I'm good.

I'm with CM. Also, Butter up the cables, selector box, shift and throttle tube so it's as good as it can be....