HELLCAT won’t start in cold

[Chinabike]

Originally Posted by Mowgli

Not yet. I ordered one and it will be here Friday. I just adjusted the valves so far but that didn’t help the cold start issue I’m having

I would just see how it goes after you put in the new carb, so you can adjust the fuel/mix screw and dial it in better. You going to remove the airbox and other egr stuff?

[Mowgli]

Originally Posted by Chinabike

I would just see how it goes after you put in the new carb, so you can adjust the fuel/mix screw and dial it in better. You going to remove the airbox and other egr stuff?

I’m not sure yet. I’d like to keep the factory air box but I really doubt it will fit with the carb so I’ll most likely use the filter that came with it.

I just went to drop something off at the post office right now and the only way I could start it again was with the space heater next to it. This sure is annoying

[Weldangrind]

I bet if you went up a size or two on the slow jet, the problem would go away.

[Megadan]

Originally Posted by Weldangrind

I bet if you went up a size or two on the slow jet, the problem would go away.

This. Go up a pilot jet size (Slow Jet in Keihin speak).

As air gets colder, it gets more dense. More dense air = more oxygen. More oxygen = needs more fuel.

If a bike is hard to start when it gets cold, it's because it is too lean. The choke is just there to block air and help correct the AFR for cold starts. (unless it has an enrichment circuit, which these dont)

Generally, a good rule of thumb for using a choke is that you shouldn't need to use full choke until the air temp is below 50 degrees F. Above 50, and your bike should start and idle on half choke from a cold start. If you need full choke above 50, and adjusting the mixture screw (if it has one) makes no difference or takes more than 2 turns out from seated, then go up to the next size on the pilot/slow jet.

Chinabikes are notoriously lean jetted across the board, which is done in an effort to get EPA certification. It makes them a pain in the rear to cold start.