LCGB Forums

Currently I have a PWK 24mm copy carb (oko) on my scoot. I am thinking of changing it for a 22m jetex. How easy would this be and what manifold would I need to complete the job? and where could I buy it.

Thanks

You can pick jettex carbs up from most dealers along with manifolds make sure you get the right manifold , small or large block and jet it correctly with the relevant slide and atomiser to suit

What's wrong with the PWK ? when they are set up correctly they are good little carbs ,

Why are you changing?
I am looking at going the opposite way because of hot starting problems with my jetex

I've used PWK copies for years now , both OKO and now the BGM type , with the correct needle installed they are cracking carbs , I have a few set up details if anybody needs any help , just ask

I got a 22 Jetex kit from ebay complete with manifold ( £34 ). The jetting was wrong but only cost a couple of quid to re-tune. A great little carb. See my other threads on Jetex.

Colin

Got to agree with you, I've got a reemed out jetex from Rayspeed running on a Classic Rapido
and it's as reliable a carb as I've ever used

The reason I am thinking of swapping my oko carb is I have a problem with starting the scoot when it gets hot. When cold it is no problem but as soon as it gets warm it is a real bugger to get going. It goes chug, chug chug chug for about a minute and a half before bursting into life. I am presuming this is a carb problem, any other suggestions would be more than welcome

First thoughts are it's flooding. Are you turning the petrol off when you stop?

Yes I do turn the petrol off when I turn the engine off,and then when re-starting I find that as it is chugging along it helps to turn the petrol off until it finally bursts into life and then turn the petrol back on. Would it be beneficial to reduce the size of the main jet in the carb?

might be the pilot jet size that's wrong , what pilot jet are you using ? and what main jet and needle is in it ??

I have exactly the same problem with my jetex! I was going to swap to the pwk to cure the problem.
Starts great cold, but when I stop I have to switch the fuel off, run it for a bit then kill it if I want it to start again.
When I restart it fuel off choke off 4+ kicks it will either chug and die or chug and catch, fuel on and it's fine.
Occasionally it won't start at all, then is air hose off (there is always some fuel in it) and it will fire after a couple of kicks, quick smart get it all built and it's off.
It does have a big mid range flat spot

parky wrote:Yes I do turn the petrol off when I turn the engine off,and then when re-starting I find that as it is chugging along it helps to turn the petrol off until it finally bursts into life and then turn the petrol back on. Would it be beneficial to reduce the size of the main jet in the carb?

Changing your main jet will not have any effect on starting as your main jet does not come into play until about two thirds throttle. Turn your petrol off a short while before stopping ( obviously not so far that you will run out of petrol) and turn it back on AFTER it has restarted without chugging. Do not be tempted to wang the throttle wide open on starting.

Rich'