being that cold you could have been cold seazing it(from the cold temps) the piston/rings could be expanding enough to slow them down at mid throttle but when you go wide open your powering through it (incorrect ring gap could cause this) this could explain not having any wash on the piston but not the oil through head/exhaust.

I would let it idle for a while to get warm before riding it after adjusting the needle but keep an eye on things.

 

I probably rode it around for a good 30 minutes so I am sure it was plenty hot. I'll try adjusting the needle this weekend. I'll also pull the plug for inspection, and see if it's running too rich. It's not overly smoky though.

 

Plus hopefully it won't be so Godd*mn cold this weekend.

 

that temperature shouldnt affect performance or relaibility. yes it should be warmed up, but ive ran my 400 in snow sleet rain etc. wihout any failure. its the hot weather that you want to look out 4. my 400 loves cold weather. hates hot weather..... at least thats wat it said the last time i had a talk with it

 

Yeah, having lived in AK for quite sometime, I've never had any probs due to cold (other than frozen batteries). I'm hopeful that getting into the carb again will help. So if I was to do a compression check, what should I be seeing?

 

I would say that 120 would be good compression for a stock motor. Anything below 100 is going to need to be rebuilt fairly soon. They need at least 80 to start. If it's starting good then it's probably not that bad.

 

dido on that duneaholic

 

So I guess what most of this is boiling down to is maybe my machine is running too rich, and when I open up the throttle it gets better? Either way it sounds like my problems must be carb related. So that's what I'll tear into this weekend.

Thanks again for all the assistance, and I'll be back with some results next monday.

 

Just a little update. I was out last weekend and got into the carb on the bike. I pulled it cleaned it again, cleaned the pilot jet, set the clip on the needle to the middle slot, set the air screw to 1 1/2 turns and reinstalled the carb. While I was at it, I pulled the fuel line all the way back to the tank and replaced it and the fuel filter. I also pulled the spark plug (which probably has about 1 hour) and it looked golden brown on the tip with a little oily residue on the threads.

Once again it started right up and sounded great at idle. No problems idling at all. Temp was about 20 deg F. Took it out for a spin and it was still missing. The power is just not there on tap like it should be. I'm really getting stumped here.

 

basically still doing the same thing, although after riding it last weekend I would say it is doing the same even when its opened up all the way, its just less noticeable.