Scooterotica

Trying to decide what pipe to fit to my RB20. Have an NK mid on it to start with but although it had power bands in 1st, 2nd and 3rd (big grin) 4th gear just wasnt there. So then tried a mates Jarspeed and bingo pulls through all gears, no power band but you cant have everything...

Anyhow, he wanted his Jarspeed back and i havent got a spare £350 to get Jarspeed to make me one, so I now have a JL2 on which still pulls in all the gears but is down power wise on the Jarspeed. I now need to get a pipe and am leaning towards a JL3 as im told these a bit revvier and give out more power. Anyone got any experience with these preff on an RB. Also how do the Frannspeeds compare as they seem to be similar/same to the JLs? Know i will probably have to get it fettled to match the RB unless i can find 2nd hand one that has had this done...yeah right...

Any other ideas for pipe suggestions greatly appreciated. This is the set up im running.

RB20
Li150 box
30m Delly, 45 main jet
Taffspeed race crank
46x16 sprocketts

Ta
Sef

Hi sef
Think ive told you this before... but anyway.
ive got a jl3 (rb modified) on an rb20 tmx35 and 4.8 ratio. 78mph (gps) thats flat out 8000rpm.
Pull well through 1,2,3 and follows on nicely in to 4th even with a gp150 box
russ

Carlos, yeah i remeber.Only diff would be the carb and sprockets i guess, what are you running sprocket wise again?

Sef

18 / 47 sprockets, std four plate clutch and strong springs.

The RB Franspeed Tourer is made by JL and is a JL3 with the correct down pipe to fit an RB. So its basically a JL3 to fit an RB straight from the factory.
The RB Franspeed Race is a pipe designed specially for the RB and from the Dyno graphs in Scootering is the best all round pipe out there for the RB.
The PM fat mamba performs well but seems to have problems with the unsupported end can breaking off.
If it was me I would forget buying a TS1 pipe and trying to make it fit an RB because you don't know what you are going to get, so buy an RB pipe that is a known quantity, there are plenty on the market:
AF Fresco
AF NK Tourer
AF NK Race
Franspeed Tourer
Franspeed Race
PM Fat Mamba
RS Performance RB Pipe
All these pipes have been Dynoed in Scootering and the Franspeed Race came out about the best All Round.

Franspeed would be nice but dont have that sort of money at mo. Spoke to Taffspeed today and they were very helpful, Sean in shop actually called up Ian to ask his advice and then called me back Think Ian was at a ralley so fair play. Great bunch of lads and highly reccomended.
Anyway he suggests that i keep the NK but get a sprocket set up of 18x47 and put a Indian 200 box in as they have a shorter gap between 3rd & 4th. This is going to work out cheaper than buying a new pipe and then getting it fettled.... Got to change the clutch plates as iv done the new ones already so may as well do it all in one go.....

Whats a 2nd hand indian 200 box go for?

Sef

sydduckett wrote:45 main jet

that's likely to be your PILOT JET

There is no need to buy a GP 200 gearbox and 18/47 sprockets, this would give you a final ratio of 5.2.
Your LI150 gearbox with standard sprockets (15/46) will give you the same ratio of 5.2. All you need is a 15t front sprocket and standard length chain to match. The LI 150 is an excellent gearbox and there is no need to change it.

CPH Lambretta wrote:There is no need to buy a GP 200 gearbox and 18/47 sprockets, this would give you a final ratio of 5.2.
Your LI150 gearbox with standard sprockets (15/46) will give you the same ratio of 5.2. All you need is a 15t front sprocket and standard length chain to match. The LI 150 is an excellent gearbox and there is no need to change it.

Is one of the best gear boxes, strong, reliable, have used this in quite few engines... 5.2 is a nice top gear ratio and no need for sprockets, chain and new gears....CPH is giving sound advice...

So all i need to do is change the 16 for a 15 and ill get pull in 4th gear? Im not saying you are wrong and believe me it is a £15 option so id be very happy, but was given this advice by Taffspeed so preumed there were not steering me wrong, im still going to have the gap between 3rd and 4th though arent I? Think thats why he suggested the Indian box as it has one less tooth than the italian..

sef