Modern Vespa

Hello!


I'm currently in a rebuild and the gears of my scoot are quite worn. The Xmas tree assembly should be trashed but the gears on the driveshaft are original Piaggio and show some wear near the cruciform contact area.

The 'budget' way is to replace the cruciform and throw in some spacers (0.65mm gauge goes in behind the circlip easily).

But in order to perform a Grade AA - first-class repair I'm thinking about upgrading the gearbox as a whole set.

I'm doing my research and on the sip-scootershop.com website there are many options but all of them are of the 'PX Lusso' ecosystem which SIP claims compatible with my scooter model which I'm in doubt actually. I don't think that the input shaft can fit the engine case nor the driveshaft on the selector box side.


So... Dear VBC riders... What kind of gearbox do you use other than some Indian aftermarket from eBay?

Yes, there may be options...
firstly; PHOTOS, we love photos, as not all VBC boxes are the same.
Is it a 2-port or (as serial suggests) a 3-port?
WHAT GEARS ARE CURRENTLY IN THERE? there are at least 3 options on what COULD be in there & they look slightly different, plus knowing the number of teeth, incl primary is important.
Otherwise we are all just guessing.

Also, knowing just how far East you are helps, as I found out if i travel to work travelling West it takes about 10min, but if I go West it is about 15015km!

In here there is something on a VBC 1 (early) box.
modify VBC1. 2-port -got fuel, need tim(ing)? Only 67mph (Page 3)

That's the average day of a Vespista....


It actually has 3 cylinder ports and a P-style crankshaft with the 19mm flywheel nut but with a ball bearing on the flywheel side instead of needle bearing (as seen on P-bikes) so it's something like a between-two-worlds configuration.


I'm getting my caliper and I will come back with pics and measurements and teeth counts later.

So I had a SIP of green tea this afternoon and took the measurements of the gearbox and its shafts.



The input shaft at the clutch side end:







The input shaft near the kickstart cog:







The input shaft-to-be from SIP:







The small engine half from the inside:






The driveshaft bearing at the selector box side (it says 6905RS):






The Xmas tree has some damage:





The new driveshaft bearing that I've got from SIP (definitely incompatible):






The first gear:






The driveshaft on the selector box side:






The cruciform:






The driveshaft on the wheel side:






The bearing seat at the primary gear:







The crankshaft bearing on the flywheel side (the one that's not black is the one which I got from SIP but it isn't only the color that differs although the inside diameter is identical):






The primary-to-be:






Vespa 150 Super 2* on the compatibility list of the bearing set:








The teeth counts are 13-17-22-27 for the Xmas tree, the primary is 67 and on the driveshaft are 57-52-48-42 I'm Hungarian and I live in Malaysia. One day if I have the guts I'll take a Vespa trip to Hungary