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yellowWB400ex
12-23-2004, 11:55 AM
I guess I should post this here. I live in NE Wisc and it just snowed a ton and now my quad runs like SH*T!!!. I have a 42 pilot and a 160 main screw 2.5 turns out with the R4 system and no air box lid. The box filled with snow, It ran horrible. Then cleaned it out and put the lid back on and it still ran horrible. I think its the jetting but not sure. It would pop when you let off the throttle and it wouldnt idle. Please help. Oh ya its any wheres 0 to 32 degrees.

smith_400ex_213
12-23-2004, 10:01 PM
put ur main jet up a couple of sizes...adn put some heet in ur gas maybe u got some iceor water in ur line too....the rest of ur jetting should be fine then too...or else u nmight have to fiddle with ur idle speed..

HondaChris
12-24-2004, 01:22 PM
I run an FMF Power Core 4, open lid, K&N filter. I have the snorkel hole blocked also. I run a 170 main and 42 pilot. All I had to do to richen mine up enough is put he airbox lid back on, and re-install the snorkel. Trick I was told to try by my dealer, to reduce the air amount instead of increase the amount of fuel. If that didnt do it, then I would have to re-jet. Runs great, and plug looks great as well. Sure beats having to mess with jetting to hit it right. It was approx 20 out yesterday, and started right up and ran great. I would go up a size or two, depending on the average cold weather temp. I have been told by many, if cold weather jetting is needed, that for every 20 degrees colder is a full main jet size increase.