Hey,

My '97 Warrior has a DG full exhaust, holes in the air box (soon to have a K&N filter), and a 150 main jet (PO work), and a new stock spark plug.

i've been having an off-idle stalling problem. as in, if i'm at idle and gun it more than 1/2 throttle, it stalls. but if i give it 1/4 throttle and then gun it, it's fine.

i adjusted the fuel screw, both in and out, and it didn't make much difference for the stalling problem.

so my next step was to adjust the needle position. the clip was originally in the middle of 5 clip positions. i dropped the clip one position to richen it. took it for a WOT run down the road. ran fine, but still stalled off-idle, even after adjusting the fuel screw. so i dropped the clip one more position to the very bottom slot. did another WOT run, and it seemed to run even better (really difficult to say better, but certainly not any worse). but it still does the same off-idle stalling, even after adjusting the fuel screw again.

at this point i was sick of playing with the carb and we decided to go trail riding. we had to travel down a long gravel road. i noticed that while cruising at around 1/2 throttle in 5th gear (any gear really), the motor seemed to stumbled a little, not bad but noticable every 10-15 seconds (rough guess). the stumbling was only noticable while cruising though, cause i didn't have any problems with it while riding woods trails. i did however notice that it popped while decellerating. the guy behind even reported a pink flame once. (yes, i have the spark arrestor in).

so what do you guys think about the off-idle stalling and the mid-throttle cruising stumbling? i'm wondering if the mid-range is too rich and i should go back up one position on the clip? the only problem with that is that it runs so well at WOT like it is. what's the next step up from a 150 jet? i could try a larger main and up the clip one spot. i'm going to go pull the plug now and see what it has to say.

i'm open to any and all thoughts on the matter.

thanks,
bigmac

 

Had somthing simular with my warrior, its still has a off idle stumble but it seems to have a accelerator problem, my stumble at 3/4 to wot was it was jetted too rich from the last owner. Seems he got a k&n jet kit and put the biggest jet that it had in it. The off idle stumble doesn't bother me too much so I've left it alone. I would go ahead and get your new filter and see how it runs then, if not your going to have to go thru this all over again.

 

I had that same problem when I had my Warrior whatever you do don't put a bigger pilot jet in I made that mistake and it caused the warrior to run awful I can't seem to remember what I did I think I might have just left it alone as for the backfire part that has something to do with you mixture screw.

 

Hey,

yea, the off-idle stalling really isn't that big of a problem, even for slow trail riding. the only time it will be annoying is if i want to race somebody.

i check the spark plug . . . definitely rich! i'm planning to go riding next weekend, so i may leave the needle alone for now and see how it runs once i get my K&N filter in. cause you're right, the fewer times i have to take the carb apart, the happier i am. lol

anybody with a jet kit know what is set-up recommended for my mods at sea level?

thanks,
bigmac

 

I have a similar problem ,although mine dooes not stall, it just lacks any power just off idle, and at part throttle cruise it hesitates. It's driving me nuts. I also have aftermarket pipe and K&N setup, I am going to raise the needle all the way to the top position and double check float hieght. I'll post back with my results. Ihave been chasing this low speed stumble for weeks.

 

Hey,

what's your current jetting set-up? when you adjust the needle, i recommend doing it one position at a time. also, is your plug black? that would indicate being too rich. if you feel like the motor is bogging down from idle-1/4 throttle, you can turn the fuel screw in to lean the mixture and that might help.

later,
bigmac

 

I've got a 142 in mine, and a buddy of mine has a e-series exhaust with a k&n and hes running a 138. Both of them run great I have 6 uni 1" filters in my lid and he's just running the stock lid with no holes.

 

Hello.
I too would recomend installing the air filter first. I also beleive the 150 main is too big. If nothing else I would recomend getting your bike warmed up for a ride, install a new plug and go for a 5 min run at that studder stumble speed not WOT. Get her home and read the plug. I suspect it will be black. You problem seems to be in the transition from needle to main. You main may be ok at WOT but the air ratio,timming, and other factors change with RPM. As they say: some times you need to step back.

 

Your stalling problem is common on carburators with out an accelerator pump. It is craving gas and i would suggest a bigger piolt. Also a 150 will probalby be about right with the K&N, it is better to run rich than lean any day. Although, you off idle problem could be a mixture not combusting becasue of a fouled plug. Change the plug and see if that help. Also you fuel delivery system may have some sort of obstruction limiting the amount of gravity fed gas.

 

Hey,

the spark plug is new. i also replaced the fuel petcock (which has the fuel filters), so the lines should be clear, and the gas is fresh. plus it runs fine at WOT, so there doesn't seem to be any obstruction limiting gas then.

we're also getting conflicting opinions on larger pilot jets. anybody else tried a lager pilot jet?

a quick question about a larger pilot jet: getting a larger pilot jet will allow it to put more fuel into the air mixture right? so really, a larger pilot is only needed once the fuel screw is turned all the way out and you still need more, correct?

Mars - you're right. the last section of the trail i did yesterday was a 10min stretch at the stumble speed. when i pulled the plug earlier this afternoon, it was black. so it's definitely running rich in the mid-range, which i kinda expected.

so naturally my thought is too lean the needle some, but it seemed to run as well or better at WOT with the needle where it's at. so that's what made me wonder if i needed a slightly larger main to help at WOT when i up the needle clip. i may just try uping the clip first though and see how that goes.

later,
bigmac