I was down at Chadwick this weekend and my 2003 Sportsman 400 with 198 hours nearly killed me. We had been riding a couple of hours when I started up a pretty steep incline at about half way up the engine lost all of its power. I was wide open in low and just barely moving up hill. I didn't think I was going to make it and backing down the hill would have been a disastorus alternative.

It happend a few other times before I could get back to camp.

I removed the plug and the center electrode looked good but the outside of the plug looked black with soot. I'm thinking a couple of things. Carb float, bad gas or something wrong with the belt drive.

Any ideas?

 

Check your belt. hot belts tend to slip. how much gas did u have in tank? the plug was cause u were flooding it out when u opened it wide going up hill. hows air filter look? could u smell gas when it happened? I'm gonna lean towards belt stretched or something there

 

you said it bogged so im assuming the belt wasnt slipping as it would be reveing up and not moving meaning its slipping. if its slipping that much in low you would notice it big time in high even on regual going. if you pulled the choke out and it run better then its lacking in the gas department. if the was set in correctly this would cause it to do it on a hill. just a couple of thoughts.

 

I have a new belt. Pre-filter and filter are both clean. The tank was full, or nearly full. There was no gas smell and pulling the choke did nothing.

"if the was set in correctly this would cause it to do it on a hill. just a couple of thoughts." If the what is set incorrectly?

Thanks for the ideas, keep 'em coming.

 

my friend has sportsman 400 and it had same problem, we had to ride close to him on climbs and push him when he bogged out. He finally gave up on trying to fix it (cleaned carb, fuel shut-off valve, air filter, etc..) and took it to dealer who said it was very common problem in 400s. They re-jetted carb and now it runs like a top. I don't know which way they went with jets, but it made a big difference!

 

<div class="FTQUOTE"><begin quote>Originally posted by: 08Renegade500

my friend has sportsman 400 and it had same problem, we had to ride close to him on climbs and push him when he bogged out. He finally gave up on trying to fix it (cleaned carb, fuel shut-off valve, air filter, etc..) and took it to dealer who said it was very common problem in 400s. They re-jetted carb and now it runs like a top. I don't know which way they went with jets, but it made a big difference!</end quote></div>

They leaned it out. Smaller number jet. The 400's did have issues with this when they came out. I have done several. I even had one guy that couldn't go across a plowed field without it bogging. Rejett it, re weight it and it should be fine.

 

i meant to say if the float was set correctly. i was in a hurry sorry. i beleave harley is correct (since he does it for a living) and i have read a few other post concerning(forgot about them sorry again) the way too rich main jets a nd a rejet did fix thier issues they had w/ flooding which is most likely what its doing.

 

I ordered a DynoJet this afternoon. Does anyone have an opinion on a clutch kit?

 

Hi guys, This post is very timely. I was giving a few of the neighbor kids a ride on our 2005 SP 400 tonight and noticed the power just wasn't there. (We came back from a 200 mile trip in Wisc. last weekend and the wife said it ran like a top then) I was on a slight hill tonight and gave it the gas from a dead stop and it did spit & sputter for a bit but then seemed to run kind-a OK, but still not the power it once had. I pulled the plug and the color seems to be perfect. The air filter was blown out and the pre-filter was cleaned about a month ago and has not been in any extreame dusty conditions since. Airbox is dry and it starts great without the choke & idles good. The machine has about 1,000 miles and 120 hours. The only other time I have the spitting & sputtering is when I'm pulling a load of wood up a steep hill in low and I have it wide open, but not gaining any quick RPM's just holding. But this time it seems a lot "doggier" than it ever. Did the early 2005 models have any jetting isues? If so would it get worse the older the machine gets? Do you have any other suggestions??? Thanks for all your help guys!!!

 

you may be at the begining of a wore out exhaust lobe on your cam(had the same symtoms with my 02 sman 400 before it got really bad), just a suggestion cause it would only take a couple of hours to check, and you would eliminate the idea