Ron Moss - Avanti TT3 - Cylinder Kit - Review & Test.....

[Lambretta Sash]

Best carb out there is VHSH 30, flows as much as the Tmx 35 with more getting/needle options. The pwk with clear bowl will b interesting but you may find fuel attacks it and possibly distort it causing leak.
. Good carbs with nice throttle response but crude too.
I've used vhsh for 3 yrs on my Avanti

[dapper]

I'm on 4.8 with a Super Tourer and 30 PHBH. Has anyone tried a 30 PWK on an Avanti ? I have a spare one an just about every jet and needle known to man so I'm tempted to try it. My main concern though is the small float bowl which can drain if the level isn't spot on. I just took delivery of a clear float bowl which I was thinking I could use to check the level is right.

Bin the clear float bowl. They swell and distort after a short while due to ethanol in the petrol.

[Rick]

Sounds like 4.8 with super tourer is the punters joice.. My bike was pulling very close to 80mph with 4.6 it didn't like a head wind mind... How much will I lose of the top end?

Cheers Warrick

[coaster]

I'm on 4.8 with a Super Tourer and 30 PHBH. Has anyone tried a 30 PWK on an Avanti ? I have a spare one an just about every jet and needle known to man so I'm tempted to try it. My main concern though is the small float bowl which can drain if the level isn't spot on. I just took delivery of a clear float bowl which I was thinking I could use to check the level is right.

Bin the clear float bowl. They swell and distort after a short while due to ethanol in the petrol.

I only intended to use it to see what was happening with the fuel level, I have heard that they are dodgy so wouldn't leave it on for general use. Cheers for the warning though

[dapper]

Col, I think you know all the mods that need to be done to the OKO carbs, like grinding out the float stop in the bottom of the bowl, enlarging the holes where the float valve is, etc. The small tab on the float itself needs to be bent a little so that as much fuel gets into the carb as possible without overflowing through the overflow tube. I have one on my Avanti and did about 1000 miles last year with no issues, albeit I never went over 65MPH (GPS), so can't say what would happen if you tried going over 70 MPH with any form of fuel starvation at that speed/WOT position. I also ran open mouth but had a load of spitback so have fitted a Breathe Sweet and have a drain hole in bottom of carb rubber and carb is dead vertical, not at an angle. And I think I'm running a bit rich.

[coaster]

.... I also ran open mouth but had a load of spitback so have fitted a Breathe Sweet and have a drain hole in bottom of carb rubber and carb is dead vertical, not at an angle. And I think I'm running a bit rich.

I'm using a breath Sweet on my 30 PHBH at the moment with a short ally adaptor ring and a short MB rubber. The filter tucks in between the tank and fan cover and the panel goes on without too much squashing of the elbow. Still getting the odd bogging down occurrence so may well try the drain hole.

Cheers

Colin

[Lambretta Sash]

Drain hole will only aid starting, should be one way valve.?

[dapper]

Drain hole will only aid starting, should be one way valve.?

No, drain hole will allow spit back to drain while standing at lights/crossing, stopping the scoot from cutting out 'cus it's too rich from the spitback and embarrassing me when I have to kickstart the f**ker, or drag her to the side of the road, turn off fuel and clear her by numerous kicks. I don't just have a hole, but a length of small plastic tube running off the drain.

[Lambretta Sash]

never had an issue with spit back tbh, they do put a little out granted.
what filter ate you using ?

[dapper]

Was open mouth but after getting back from Brittany last year the scoot was filthy from all the spitback right back to the rear wheel so trying a Breathe Sweet this year.