Re: Lambretta jetting help please! 175 Li
Posted: Mon Jun 13, 2016 10:16 am
I thought I'd update this thread with what worked.
The problem with starting was not caused by it being too rich, it's caused by it being too lean. I increased the pilot jet size and I haven't had a problem since. My jetting is now very close to a TV175 Series 3:
50 pilot
50 choke
108 Main (I may increase this to 110 after a plug chop)
5899-2 atomiser
5914-1 slide.
I'm running the kit throught an unmodified '63 airbox, with a GP scoop. Exhaust is a KBR clubman.
It's reasonable to assume it's too rich when it smells of petrol and there's petrol dripping out the carb as you're kicking it over for the umpteenth time, but the problem is actually it being too lean - fuel is not being burnt and is being sent back and flooding the carb.
Hopefully this will help someone who is experiencing the same problems - I certainly read a few threads when I was trying to sort mine. It's not taken more than two kicks to start it now, whether it's hot, warm or cold.
The problem with starting was not caused by it being too rich, it's caused by it being too lean. I increased the pilot jet size and I haven't had a problem since. My jetting is now very close to a TV175 Series 3:
50 pilot
50 choke
108 Main (I may increase this to 110 after a plug chop)
5899-2 atomiser
5914-1 slide.
I'm running the kit throught an unmodified '63 airbox, with a GP scoop. Exhaust is a KBR clubman.
It's reasonable to assume it's too rich when it smells of petrol and there's petrol dripping out the carb as you're kicking it over for the umpteenth time, but the problem is actually it being too lean - fuel is not being burnt and is being sent back and flooding the carb.
Hopefully this will help someone who is experiencing the same problems - I certainly read a few threads when I was trying to sort mine. It's not taken more than two kicks to start it now, whether it's hot, warm or cold.