95 typhoon 50, need help with overrange please

I have a 95 Piaggio Typhoon 50 that was shipped here to the USA from Spain. I need some experienced knowledge from you fine people. I have the correct "pre-98" Malossi overrange kit for my scoot. I've begun to grind the carter out in order the fit the overrange kit but I stopped when I felt I was getting pretty deep on the gearcase cover. My gearcase cover is the one with the exposed bearing cap for the final driven shaft. I'm having to grind pretty deep directly over that bearing cap. Anybody here done these mods to the old tec1 type A/B (Hi-Per1) engines? Also can I just upgrade to the ET2 (Hi-Per2) primary and secondary gears and then use the Polini gear cover that is already clearanced for an overrange pulley set up? I thought I read somewhere that this was possible but I can't find it now. Anyway, if I don't require the ET2 (Hi-Per2) parts and can safely grind it down to fit that would be great seeing as I already installed all new gear upgrades. I've already rebult this motor top to bottom, bearings, seals, crank (Jasil), top end (Polini Corsa), V-Force 3 Reeds, Polini CP21, and ready for the overrange. I greatly appreciate anyones experience with these older piaggio 50's.

It is a TEC1 stamped carter and extremely rare in the US because Piaggio didn't import here until 2001 with the ET2 (Hi-Per2) engines to start. Nobody knows anything about these here.

 

I know a little about typhoons, I'm not sure on what your doing though, overrange? Variator or gearkit? I've not herd of anyone needing to grind cases ! Put some pics up.

 

Yes I'm installing a Malossi overrange kit. In order to fit the rear pulley the case needs to be grinded in a few places for the pulley to slide all the way in and the bearings to seat properly on the shaft. It's getting close to seating but the outer rim of the pulley is still rubbing against the gear cover even after notching it a few times. I'm scared to grind further because its getting fairly deep in to the bearing pocket of the gear cover. I know this is an easy one for people that have done overrange on these older Piaggio Hi-Per1 50s. Its my first Piaggio build so I want to be sure. I've done plenty of Minarelli horizontal builds but I want to consult the Piaggio experts across the pond before I grind too far. I'll see if I can post a pic from my phone. Thanks man

 

https://www.tuningmatters.com/revie...o-engine-differences-hi-per-2-vs-piaggio-old/

Over here the opinion is that these older engines are inferior, and so there aren't many people who've modified them very highly!

You do have to grind them - but the area you grind differs on those old cases. This is what the c-one/evo/stage6 gear covers are designed to fix - but again I've no idea whether those will work on the tec1 gearbox.

My best advice is to find some nice scooter rider who can ship you newer cases..probably 10x easier in the long run when you need to replace things

 

I have a malossi torque driver on my Runner 70cc.. and as you may see I had to grind some of my case away.