Hardcore Sledder banner

1 - 7 of 7 Posts

·
Registered
Joined
·
153 Posts
Discussion Starter #1
I have an 02 zr 500 and I have been having some problems with the idle. After the sled has been run and it is hot, it just about dies when I stop for a minute. Flipping the choke a little makes it worse so it must be a rich problem. I haven't cleaned the carbs yet and I am definitely going to. I can just about gaurantee that cleaning them will cure the problem. My question is - what part of the circuit would cause it to go rich when it gets dirty? I have heard of the pilots getting dirty and causing a lean condition and a poor idle. That situation doesn't seem to match up with my problem though?
 

·
Registered
Joined
·
61 Posts
Make sure that it is not one of your chokes hanging up slighty. It should have some free play under the lever ( 1/8" ).

ZR 900
 

·
Registered
Joined
·
3,141 Posts
I'm not familiar with the ZR500 TM-38 carbs but if they are like the TM-40's you may want to verify the air screw settings. The air screws control the idle circuit and closing them will allow less fuel to be pulled through at idle.
On flatsides the airscrews are on the right side of the carb intake and nearly covered by the airbox > carb boot.
My service manual CD advises that the '02 ZR500 should have been delivered with fuel screws set at 2.0 turns out and the pilot air screws at 1.5 turns out. Check yours. Mine where incorrect from the factory.
Good Luck!
 

·
Registered
Joined
·
153 Posts
Discussion Starter #4
Actually I just found out the fuel screws were set incorrect also. One was out 4 and one was out 2. I'm kinda stumped though cause it ran pretty good last year set like that. They are both set at 2 now and air screws are at 1.5, but didn't help any. I changed jets and noticed some small debris and aluminum came out of the bowl when they were drained. Would a needle that isn't seating because of debris cause a rich idle?
 

·
Registered
Joined
·
6,976 Posts
ALL new cats have the aluminum shavings in the float bowls. It must be from when the drill the drain plug hole. Guess what happens when one of those shavings gets stuck in your mains. Burn down. Every new sled should have the carbs cleaned before ran. No one I know does it, I do know a few who have burned down because of it.

As far as your idle. Check all the specs, sync your carbs, and clean them. You might have a dirty pilot. If all that checks out. I dunno.
Cat S.
 
1 - 7 of 7 Posts
Top