Scooterotica

Hi guys,

I'm about to start building my engine for my series 1 framebreather

I'm going to build a gt206 engine
I want to use the original case from the scooter but was wondering what the differences are?

I know the mag flange is different, but it seems to be different around the main bearing

I was thinking of machining (with my dremel) around this area to make it the same as a s3 casing... Any thoughts on this? And is there any other differences?

Thanks in advance,

Dryballs

I wouldn't risk a tuned engine in a SI engine without upgrading certain components, especially the mag flange. I don't think there is anything stopping you using an SIII flange and a decent crank, so why not do it. Can anyone confirm this?

On SI engines, there is no dished oil thrower behind the front sprocket, but as no one has explained to me what this oil-thrower does (apart from "throw oil" ), I wouldn't worry too much.

...I used a GP-crank an a GP-maghouse in my s1-engine...no problem...

Wellerchap's done this with his Mugello, if you give him an IM on WKFASC He'll tell you what he did.

i have dione it too, tameni gp crank and ser. 3 mag, i did take the dremel tool to where the oil throw washer goes, i would only think that it helps the oil lubricate the main bearing far better and easier. i run a deanspeed 190.

Yes I have a GP Mag housing and crank, 5 plate clutch & chaincase on an S1 case with no problems....pretty much just the casing & gearbox is S1 now.

Someone also told me S1 rear hubs were pretty good for tuned engines anyway as they are a thicker cast than the S3 or new patterned ones..I used one anyway because I had one.

Apologies to jump this thread...but will using S1 150 gearing give you a different ratio to S3 150 gearing? Anybody?

Thanks Stu

mawso wrote:
Apologies to jump this thread...but will using S1 150 gearing give you a different ratio to S3 150 gearing? Anybody?

Thanks Stu

Same.

If I remember correctly the Series 1 chaincase cover doesn't have the strengthening webs around the kickstart exterior and are prone to breaking on tuned engines. Adults please

dapper wrote:If I remember correctly the Series 1 chaincase cover doesn't have the strengthening webs around the kickstart exterior and are prone to breaking on tuned engines. Adults please

Thats cool... It wont affect the rest of the engine tho

Although if anyone has a spanish side case they want to sell me let me know!

Alternatively can you use a series 3 side case?

Alternatively can you use a series 3 side case?

yes they are all interchangable.