I am still trying to smooth out a bogging area on my lml pinasco 177, slight bog on low throttle then off like a rocket to around 60mph. Shutting off, i do not get the normal sound of the engine thud, thud, thud to tickover. But will immediately respond on throttle to accelerate, it can be a bit sudden. I have never had a reed valve engine before, does it cut fuel off immediately during throttle off, or does it allow the engine to fire until tickover. On my lambretta on shut off i would have a pang,pang until reaching engine tickover. I hope I have explained it without you thinking I have lost it, but I am old generation and listening was the main way to tune. The lml is just sounding different. Plug chop nice brown, down to 110 main jet, could it be the idle jet? I am using the pinasco recommended jetting. Hope someone can advise.
I know what your saying, an old BSA Bantam d10 I had, did the whole slow pang- pang- pang thing until tickover (used to love that sound) but my LML never has. It seems to reach idle quicker much like My Honda H100a which is also a reed valve 2t. Sorry, but I’ve never had a non reed valve Vespa / Lml to compare.
Thanks for your reply, at least I am not nuts!!! You knew what I meant at least. My previous vespas would thud , and then thud,thud and so on, on long shut downs to a junction from speed. My lml doesn’t, but if I touch the throttle it responds instantly. Everything seems fine, just my first reed valve so I am confused if still too rich or just the idle jet, or if it is normal. Sounds that it is a reed valve thing, that is closing to conserve fuel when not needed.
any other opinions out their? cheers Roosevelt