# Idle issues



## Waddaman (Oct 3, 2010)

To give this some back ground, I did some work to my brute a few weeks back and have had trouble ever since with idle. 

What I did: Installed YFZ Catch Can, Muzzy Duals, Red Secondary(belt was then too tight, more info later), Valve Lash(done correctly), MTX-L A/F meter, and a 2012 starter gear.

Symptoms: In gear the bike will sometimes stall, In neutral if I touch the throttle the rpms stay high and don't drop down the previous and proper RPM. NOTHING else is wrong with it, this is the only issue. Rides fine but as soon as I let go of the throttle sometimes it will stall in gear, in neutral if I blip the throttle it will stay high RPM and I need to adjust my idle to shift then readjust up before it stalls. Stalling in mud as soon as I let go of the throttle will not be good, and that's what im trying to avoid.

I first thought it was a vacuum leak, I took my carbs off and inspected carb boots and sealing surfaces for head to boot-boot to carb and it was clean as could be. The boots had hairline cracks on the outside, but I pulled on it and moved it looking on the inside to see if I could expose a hole but I couldn't find a thing.

My belt was also tight, I thought it might have something to do with it because under load(in gear) it was stalling and in neutral it would rev really high and stay there. My belt would squeak very slightly through my snorkel at idle, it did NOT move the bike. I took the cover off to see a month old belt already ruined because it was too tight (irrelevant but made me angry). I took my secondary off, and added a .3mm shim (When tight it had a 1mm). After being sick all weekend I took it out to try it again just a few minutes ago, let it warm up fully and my idle was still doing the exact same thing. My belt no longer squeaked though.

Ive been doing research and asking around, and Ive narrowed a few answers about fuel supply, crank sensor, and a few other things. But I can't help but think it has something to do with the mods I did because it was perfectly fine before I did them.

Any info to help me get back to mudding before the best time of the year for it is gone, is greatly appreciated, Thank you.

Edit: to add one more thing, my idle mixture is 11.4-11.5 at proper idle RPM for the rear cylinder, haven't had a chance to switch cyls and do testing on both yet.


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## dman66 (Feb 20, 2011)

Have you actually checked the throttle cable at the carbs,under the carb cable cover,to see if the cable returns closed after applying throttle? Just throwing it out there for ya.


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## Waddaman (Oct 3, 2010)

Forgot to add that sorry, neither throttle OR choke cable are binding. I took the choke out and it was clean and sealed also. And I drained the bowls and inspected jets/dump lines and all was fine also.


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## Waddaman (Oct 3, 2010)

I was out today and I thought of something. (I forgot to add on top of thread that I installed an MTX-L A/F meter also...) I am getting E9 error code on my A/F meter randomly which means low voltage. Is it possible at idle that the alternator is not producing enough power at idle and causing this?? Is it possible that an A/F meter would take that much energy??


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## Waddaman (Oct 3, 2010)

I was out today and I was trying to lean out my idle A/F a bit for my rear cylinder (have an A/F meter and it's running 11.5 and it should be 13.5) to reduce possible problems. I turned it in (to reduce fuel) a half turn, and it only went from 11.5 to 11.7 which I thought wasn't enough for a half turn. I continued to add another half making it 1 full turn in. It then just went back to 11.5??? Could this point to an issue?


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## JLOWERY (Jan 30, 2010)

13.5 seems awful lean. I was told anything over 13 is getting a little dangerous. Mine is at 12.8 WOT and runs pretty dam good plugs look almost perfect.

KAWI RULES


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## Waddaman (Oct 3, 2010)

13.5 from idle to half, 12.5 from half to WOT as I was told by dale who makes my kit. Anyway that really isn't the main topic here lol.


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## browland (Apr 4, 2009)

Here's a question, when you pull the carbs loose , if you do like I do to pull the bowls I take and twist the carbs upside down. With the cables still connected . I have caught myself a few times when putting it back together turning it over to install the wrong direction twisting the cables a full turn. It will go back together like that . But the cables are tight. 

Second- don't know if you have replaced the pilot jets during all of this but I recently bought some from jets r us and was sent an oem equivalent instead of factory. Well I tried the larger off brand and at idle it would never be consistent on idle , it was all over the place and almost 4 turns out on fuel screws. Maybe neither of these help but they are issues I have ran into. Good luck bud


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## Waddaman (Oct 3, 2010)

I checked my cables and they were fine. Made sure not to flip it the wrong way, ive almost done that myself a couple times as well but that's not it. I took the throttle cover off and moved the throttle to check it and they open and closed properly before I put everything back on.

My pilots are #42s which were the same I had on the big gun, and before I changed the exhaust it was fine....

All I know is I wanna go deep real bad, and it's been raining all weekend/all this week and I can't


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## browland (Apr 4, 2009)

Hey I just had this happen to me this weekend. Take and loosen the throttle cable where it enters the side cover, where you can adjust the cable tension. That has to be it. Loosen it up where you have an 1/8 inch play in the throttle lever. Seems silly, I tried to take out all the play and had the same issue you are


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