Drillbit

Update. After taking the carb back off and closer inspection I noticed that the throttle plate was opening to much before the main needle jet even moved any. I have attached a picture. The linkage arm that connects the two had so much play in it that one was opening and the other wasn't doing anything. You can see that I have the idle adjustment screw all the way in and it still wouldn't idle and the choke plunger didn't have any affect when trying to start it. Anyway, By putting a carb kit on it does nothing for this linkage problem so I went ahead and bought a new cheap carb. Put it on, works great. The air/fuel screw now works and the choke and idle screw actually does something. This type of thing can be a gremlin to find. Thanks Mech and Gwbarm.

Thanks Gwbarm and Mech for your input. I also am having a hard time believing these plugs are fouling so quickly even if rich fuel. I did a compression check initially but the motor was cold and got a 125 reading. That seems to be good but I didn't check that when motor hot. This has a Mikuni carb on it and I put a new kit on it. Yes, I've read alot about those aftermarket kits not having the right size jet holes and things but, Damn, I have no way of telling if the hole sizes are correct. I'm almost thinking about putting the old jets and seats back in it. The choke on this is just a manual push/pull knob type. It's not automatic but it sounds that way when I start it. You don't think the intake valve not seating good would cause this do you? Like I said, it runs good.

Hey all, I need some input on a problem I'm having with my Kodiak 400 that keeps fouling plugs. First off, I've done a lot of work to this thing, most of it all in good fun. Brake work, cv joints, u joints, carb kit, checked valve lash, compression good, changed all fluids, etc... My problem is it keeps fouling plugs very quickly. I can put a new (manual recommended plug) in and it starts right up, runs great, idles great, picks up good. Doesn't stutter at all. I ride it for 1/2 a mile, it cuts off and won't start back up. I let it sit overnight thinking maybe it got to hot. Try to start it the next day, nothing. Put a new plug in, fires right up, runs great for another 1/2 mile or so, dead. The plugs come out and look carbon fouled with dry black soot on them. I don't know if this is a fuel/air mixture problem or a ignition problem. A couple of things that I noticed is I never need to pull the choke out to start it. Also, when it starts it automatically idles high like an automatic choke would do, then it comes back down to a good idle. Also I noticed that the air/fuel mixture needle valve screw does nothing when I adjust it in or out. I can screw it all the way closed and the motor still runs and idles good. Any advice would be greatly appreciated. I'm almost leaning to a ignition breaking down the plugs?? Thanks!

Hi all, from Virginia here. This winter I bought a old Atv to tinker with and have really enjoyed it. Thanks for this forum.