190 not starting in cold. Please help

[Supereibar]

I have done a modified 190 kit for a friend. Yam rod / Suzuki piston. We have put a 42mm AF pipe and an already set up 25mm PHBL dellorto from MRB. We have placed the carb straight on as it comes off the box.

We tried to start in cold but the scooter will not start unless is push started. Once started, then it can be turned off and started with the kickstart no problem.

Things we've tried without success:

1-Putting petrol directly into the plug.
2-Choke on without / with air bellow.
3-Pulling the choke cable directly by hand just in case there wasnt much tension.
4-Changing plugs (using an N4C Champion)

Still after all this, the scooter will ONLY start in cold pushing it downhill.

Any ideas would be gladly appreciated.

All the best,

Jaime

P.S: I forgot to say that I have completely rebuilt this engine from zero.

[sdjohn]

Whenever I hear that a scoot will only bump start I go back to the same thing - check the compression.

Usually the answer comes back that it's low.

If you don't have a gauge it will be worth your while to borrow one.

If it's high then you can move on to multiple guess with carburetor and spark and all that.

[coaster]

I'd have the carb apart and check what size choke jet is fitted.

Does it start from cold of you hold a cloth/hand over the carb when you kick it?

[mark]

I'm with coaster on the choke mate

[RICSPEED]

have you gapped the plug ?