Hey guys i really need some help here. I live in northern MI and its startin to get cold. My 400 2-stroke never did run great in the winter but this year it really sucks. It starts fine and runs great for about ten minutes and then quits like it runs out of gas. I let it sit for about 15 minutes and it starts right back up but only runs for about ten min. again. The only thing i can think of is one time last summer i was ridding and the damn air filter fell off and i didn't notice it untill i got home. I got some dirt in the carb and scratched it up pretty good where the piston slides up and down(in the carb not the motor) and it wore the coating off of the piston. The other day it started to rust and was sticking so i took some emery paper and sanded the rust off( i know its not a good idea but i had to do something). Is it possible that the carb isn't sealing up and its loosing pressure through the slide and not sucking gas in? I think I'm gonna get the Mikuni 38mm flatslide anyway but do you think this could be why its quiting on me?

Thanks

 

Carb is most likley freezing up. Happens when the temps are below freezing and the dew point is close to the present temp. Could also be condensation in the tank/lines/carb you should run with a little isopropyl gas line anti freeze. Read thisWinter Tips

 

I would agree with snowride, I have to run heet in my atv's and snowmobiles, just a little water in the gas can cause many problems. ever ride in the u.p.?

 

HI YooperMike,

I was just in the U.P. for the long weekend with my wife runnin' our four wheelers at the in laws house in Newberry, and their cabin north of Mcmillan. It was great, and the snowy county roads were a great playground. I didn't have the quads when I went to MTU, but I had my Jeep, and the trails up in the Keweenaw would be outstanding atv trails. Any good trails around Marquette??

"Z"

 

Well the carb was freezing up but my main problem was that the vent hose comin off of the gas tank fell down beside the pipe and it melted it shut. Cut the end off, moved it to a cooler spot and she runs great. I'll try using some heet in the gas. Yooper yes i have ridden in the UP. We go up every year (5 of us) to Twin Lakes at Krupps Resort and ride everyday all day for a week. There is some great riding up there.
Thanks for all of the suggestions.

P.S.

Heres a story for ya. Tonight I sat in the basement and put 448 studs in my old tires to try and get some traction in the snow. Well it took about 2 hours to put them all in and then about 2 minutes on my track for them all to fall out. Oh well worked good while they lasted[img]i/expressions/face-icon-small-blush.gif[/img]

 

You're doing it the wrong way. I have been running studs in winter for 10+ years. My sp 600 has 588 studs. I would say that traction on ice is similar to loose gravel. You need to bore holes first, then using the proper air gun, insert carbide tipped automotive studs. You will only lose 1 or 2 in a thousand miles. I always have mine done by a local guy up here. I'm almost embarresed to pay him because I feel its way to cheap. How would you like to drill 588 holes and insert and supply 588 studs for $100 CDN ($60 US)

 

hi zak, most of the riding i do around here is on the snomo trails, but there are lots of 2 tracks to ride on too. If you get out of marquette county there are some counties that let you ride on the roads so you can get to other places without trailering. lots of good places to ride and i'm still learning them! just about time to put them away though[img]i/expressions/face-icon-small-sad.gif[/img] then comes snowmobiling[img]i/expressions/face-icon-small-smile.gif[/img] later!!

 

I was gonna suggest that Hughes, I had the same thing happen to me. By the way, I have the 38mm Mikuni and it is a great carb.