Carburateur problem?

Excuse moi je parle just un peu de Fraincais. If I'll try to write French you'll burts into laughter. I hope that someone wants to help me in English. Perhaps some of you would translate my problem in French.

My 348 has worked really fine one year but now there seems to be some kind of carb problem (Amal 2627). I can't get the engine work properly, and I can't adjust the idling as I did last year. The idling is either too high or the engine will stop. I have dismantled and cleaned the carb and airbox and everything seems to be OK. Last year I got a new slide.
When the bike is in place the engine rpm's rise fast when turning throttle. But when decreasing throttle the engine rpm's don't decrease enough fast. Strange and dangerous too!

Any ideas what to check or repair?

Hi Esa

I'm not an Amal carb specialist but I can try to help you

2 ideas for your concern :
- clean your idle nozle (as described your mix seems to be lean on idle) and put factory idle settings on your carb
- are you sure that your slide is mounted in a proper way? sometime needle clip can leave and needle falls down in diffusor

Cheers and keep us informed

Thank you RedNeck for your help!
I'll done what you adviced but the fault wasn't there. No air leaks to be seen. The engine takes fine high rpm's, so there can't be anything wrong with the ignition?

Hmmm I don't believe that's an ignition problem...
- Do You ear the sound of your slide when you release throtle?
- did you checked extra air intake around carb assembly and between cylinder and carb?

I can hear the sound of slide - but only if the engine doesn't work. When the engine works there are too much noise to hear the sound of tje slide. I think that the slide works freely.

I haven't found any air leaks. The intake tube and airbox tube are in good shape.

There was two faults: leaking right crank seal and broken condenser! That's why it was so difficult for me to find out what was wrong.

hyvää päivää
why don't you say :" perkele " i think after you feel better
Greetings
Paul from France (born in Helsinki)