My quad dies when i let off the gas

[sykoz]

Well since i installed a full exhaust+hmf fuel controler on my bone stock yfz450r i noticed that when im for example. On a track going to a turn im in 3rd gear and then i pull the clutch and the brake both a the same time and i downshift into second gear. The problem is when i do that without pulling the throttle at all the quad just dies and i've to restart it. Any idea ? :x

Sorry its hard to explain my main language is french so if there's anything you cant understand just ask me and ill do my best to make it more clear.

Thanks

[Mike/HMF]

Are you running with your air box lid on or off? You will make more power with it removed. Regardless, you are either Rich or lean on your first mode. With the engine warm and idling set mode 1 to the highest smooth idle.

[sykoz]

I still have the air box lid on , planning on removing it as soon as i get a new air filter+prefilter . And hm you mean i should go in mode 1 and go up a bit in the numbers ?

[Mike/HMF]

Not necessarily up in mode 1. You may actually have to go down. You are looking for the highest smooth RPM with the engine idling.