reed valve recommendations?

[Diablo]

I set a scoot up last weekend with the marchaud filter on a muggy 186.
I did find that it richened the jetting by a significant amount and was more restrictive than a ramair.
It may help though because the spitback won't collect to be sucked back into the carb.

Has the barrel been ported much? We've set up 3 RTs up and the porting seems relatively conservative in standard form so I'm wondering if your carb is not just overjetted.

The remote filter set up will be less forgiving of overich jetting because it will collect the excess. With a correctly jetted carb they often help with fueling though and can act a bit like a bellmouth.

The thing is that fuel will collect in the hose from any part of the jetting that is rich. The needle may be weak but the main jet rich but the fuel will still collect in the hose and may even make the needle setting seem ok. When you come off the throttle a correctly jetted pilot will choke up and seem rich.
You may find that if you remove the filter and hose and jet the carb areas where its rich and lean will be easier to detect. Get the carb set right then refit the filter and adjust as you need to.

Drill a small hole in the bottom of the hose because it doesn't matter how will set up it is it will always spit a little.

If the motor sets up nice without the filter and without chucking fuel all over the runners its not the motor thats at fault so it doesn't need a reed. In fact you will probably lose power for little benifit in return.


Of the 3 RTs ive ridden I can't say one of them has made me think this bike needs a reedvalve.

[minotaur]

thanks for the advice, i'm going for a run out the weekend to have a fiddle, the RT is standard , no mods,... thanks to earlier advice i now know that my main was too rich and although not boggy at w.o.t definately affected jetting low down, common in pwks i think.

i'm going to put a 1mm hole in bottom of remote elbow but want to bond a small diameter pipe underneath to drain away, so as not to cover engine with mix, any tips on fuel resistant rubber glue would help

i took off my ram air which has filter oil and swapped it for my mates new bigger ram air from cam lam with no filter oil and the initial reaction was better, i'll try everything out the weekend

i've jetted a 24mm pwk on my casa 185 kit with ancilloti with great success, the RT is just run in at 1200kms so must have lost my way a little re jetting along the way, plus its cooler now of course

[SpanishSX200]

Very sound advice from Diablo. I will be interested to see how you get on. Don't forget my standard RT230 is running a 108 main, try it, you might be suprised how cleanly it picks up. These PWK's are really responsive to main jets. Simon

[minotaur]

oh, one more thing, i am running with an agusto system to retard timing, set up seems fine and i have fitted a few and like a lot, but can adjusting a degree either way help reduce spitback also???

[minotaur]

ok filter off scoot on stand getting spitback on tickover, not any where else will reduce pilot from 38 to 35 to see if it helps , air screw achieves nothing at this time regarding spitback

[nellyboyo]

Sorry for the late reply Minotaur, yes I modifed the piston but no boost port and it was running great but I was paranoid about the steel reeds that were fitted.
Sooooo I bought 2nd hand reed blocks with Boyesen glass fibre reeds fitted . These changed the behaviour of the engine as they were lighter and the windows bigger etc etc.
I felt it wasnt right with these petals either so I`d just come back form my mates ( on small wheels ) to order thicker carbon fibre reeds reeds .
But what I didn`t do was rejet so yesterday I holed the sodding piston . :flaming:

the most annoying thing is its all my fault

[minotaur]

sorry to hear about piston , ouch ,

i put a small hole in bottom of elbow, fair bit of dripping, especially on tickover, lowered main to 110 and ended up lowering clip one air screw 1 3/4 out 35 idle, and sooo much more rideable,... no splutter low down, making a nice mess of flywheel cowl and inside of running board , once i have glued an evacuation pipe to underside of bellows i am in heaven, thanks guys, its true to say its impossible to jet without this little hole in the bellows...