175 ally kits

[neil64]

Hi
Anyone using any of the 175 alloy kits ' your thoughts on quality especially the ones supplied by R........speed and B......speed ' do they need fettling and what's the compression like '

Yer thoughts ?

[davla]

I've just fitted a 200cc ali kit from AF Rayspeed, only just starting to run it in but so far so good and it runs really nicely. Compression is about 120lb

[Roey99]

Just fitted a Scooter resto's kit to my Li 125 bottom end.
Had the ports, inlet and exhaust cleaned up and the 150 head re profiled to suit.
Used a quality Italian piston, probably wouldn't have fitted the kit without getting it professionally tidied up first.
I'm struggling with set up of the exhaust side of things, plus the gearing as been an issue.
( see my thread in the series 1,2,3 section )
On track to get it sorted, looking carefully at the exhaust options.

I prefer to use Scooter Resto's as they have always looked after me well plus the parts supplied are generally good.

jr

[Storkfoot]

Going back a few years, I ran an SR175 and Sr 185. Both were okay. It was only after I sent the barrel to MB to have a “fast road tune” that the engine came alive though (ran it with a TM24 and an under k/start Fresco)

The steel liners are soft though.

[davla]

Going back a few years, I ran an SR175 and Sr 185. Both were okay. It was only after I sent the barrel to MB to have a “fast road tune” that the engine came alive though (ran it with a TM24 and an under k/start Fresco)

The steel liners are soft though.

The AF kit comes stage 4 tuned and with all of the gaskets and a manifold for a 22mm Dellorto or Jetex and is ready to bolt straight on. I still checked it over though and spent some time fitting it properly.

[Scooterdude]

Don't be tempted to get one of the "eBay specials" they really are dire, I've got one here I'm stripping back off a scoot for someone nothing but trouble, a case of buy cheap buy twice.

[Adam_Winstone]

"The steel liners are soft though."...

This has eventually been the factor that has seen a number of these being removed from bikes in my club, regardless of where they've been sourced from. That said, they served well for anywhere between 1,000 and 6,000 miles before wearing the exhaust port square and then breaking rings.

My advice for anyone fitting one of these would be to leave the exhaust width as narrow as possible as any additional widening speeds up the wear process to the port edge and eventual ring breakage. That said, one of these did do a number of Euro Lambretta rallies and other distance rallies, but I kid you not when I say what it wore the bore out at least 3 times, always starting with a well shaped / chamfered port, and always ending up with it square again (hard ring machining soft liner, made worse by dealer porting spec'). He also went nowhere without a spare piston, getting through lots of pistons over the years!

Adam

[EddieStone]

Personally I'm not a fan of cheap ally kits, I'd rather get an iron barrel bored out.