EX500 Idle Issues

[ckyguy68]

Ok i got my bike running pretty good today, considering i had the engine apart just a few nights ago. It runs AMAZING after idle, but its really tricky when idling.

The throttle response is bad at low rpms and it almost sounds like there is a vacuum leak. If you dont set the idle screw high it wont idle at all. The thing is when i set the idle screw high, once i start ridding the bike and let off the gas it idles at around 4-5K. Its really irritating and makes the bike hard to ride. I dont have the sides on the airbox, would that cause it to act that funny? The bike pulls really hard after an idle! Any help is appreciated!

[Gringoloco]

Have you tried to adjust your throttle cable any? Why did you have your engine apart?

[ckyguy68]

I had the motor apart because the cam timing was off thanks to its previous outstanding mechanic. I know its not the throttle i purposely left a little slack on the cable to clear that theory. Could my needle adjustment be a little too rich? What about the mixture screws?

[ckyguy68]

By the way it has dynojet needles and F1 pipes.

[ckyguy68]

anyone???

[midas6t6]

The needles won't have much effect, if any, on the idle. Is cam timing all you did? Did you try sychronizing the carbs? Did you do anything to the carbs while they were off?

[ckyguy68]

I cleaned the carbs VERY well while they were off... i changed a needle position and now the bike doesnt pull nearly as well. hmmmm.......

[midas6t6]

I'd put the needles back how they were, adjust the air screws to be sure they are adjusted equally, and synchronize the carbs.

[ckyguy68]

Well today i put the needles in the 3rd clip, and took the sides off the airbox. Both fuel screws are 2 turns out. The bike idles alright, and pulls really hard at higher RPMS but its a dog low end. Ive heard these carbs are hard to tune, so im not to disapointed. Could i do anything with the fuel screws to make it a little better? I would say its a little rich right now...

[midas6t6]

Try turning them in 1/4 turn. I'd put the sides back on the airbox and drill a 1" hole parallel to the intake horn. Read this post - it's a common racer mod. With the sides off the airbox you're probably too lean down low.
Login

[ckyguy68]

This is how its running today. Im not sure if its running strong or im just fooling myself. How does it look/sound?

Video of bike - Photobucket - Video and Image Hosting

[midas6t6]

Sounds good. What did you wind up doing to it?

[ckyguy68]

i turned out the mixture screws about a 1/4 turn and it behaves much better. It has a flat spot still but its tolerable.