Scooterotica

thinking of fitting a racetour piston to my rapido, are they as good as a jap piston [ie honda] anybody used one in a rapido kit. cheers

I was told that Rapido's were notorious for having a pretty soft bore, and that the racetour pistons hard rings weren't best suited to the sometimes soft bore of the Rapido. That said, I know there are loads of people running that combination with no problems at all.

I trashed a couple of Rapido's last year (one with a racetour piston). I had the second one checked for hardness by a very reputable tuner. It was found to be very soft. In fact the quote from the tuner was "it's not good when the carbon deposits are harder than the barrel". Of course that was "tongue in cheek" but you get the jist. It's a personal thing but i'd say steer clear of that combination.

Marty

I've been running a Rapido for just over a year;

Started off with a Mahle: Seized within 200 miles
Then an Asso: Rings wore out after 500 miles
New Asso Rings: Worn out after another 500 miles!

I was told that the rings were too soft, not the bore?

Now I'm road testing a RaceTour, bore now oversized to 225, done 600 miles, no visible wear on the rings, goes like a rocket!

I do have some other issues that I'm trying to resolve as I think the ports are too big and not closing properly, which causes the engine to rev on when I select neutral and sometimes between gears?

Race rappido's are over ported for the road, best bet is to get them relined with a better grade lining and change the porting then fit a rev tour piston. this compination is the answer.
Same could be said for the classic rappido except the porting is ok.

ScooterLoopyJohn wrote:Race rappido's are over ported for the road, best bet is to get them relined with a better grade lining and change the porting then fit a rev tour piston. this compination is the answer.
Same could be said for the classic rappido except the porting is ok.

Rev Tour? Never heard of them? Who sells them?

the Rapido on my race engine runs a Suzuki piston with a single ring......... considering the porting and hammer..... they work well!

paulmgreen wrote:the Rapido on my race engine runs a Suzuki piston with a single ring......... considering the porting and hammer..... they work well!

67mm RM....??

yes mate - 67.0!

paulmgreen wrote:the Rapido on my race engine runs a Suzuki piston with a single ring......... considering the porting and hammer..... they work well!

please, can you tell us some more details about the engine.


fishi

Ran a Wiseco Jets ski piston for a whole summer season, wringing it hard, bore ok, rings needed to be changed, about 3000 miles I reckon. Ran low primary compression, air box, no filter.