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Discussion Starter · #1 ·
Hi, I have a wildcat 650. I did some major face lifts to it. ie... put 1998 ett rails in it, reverse in it, and black magic A-Arm kit to widen the skis.. now the problem is,, last year when I got it.. we road the hell out of it.. we went through like 5 sets of plugs, in like 200 miles what it does is, we ride, and then stop for a few min. then when we go to take off it boggs,, if we play with the throttle (pump it) it seems to pick up and seem fine for a while, then it does it again.. all in like 40 miles.. the time for new plugs..then it is fine. and we go through the whole deal again. BOG/PLAY/ AND GO... I am using BR9ES plugs, (what it calls for..) when it rins, it is a very fast sled. I had it on Lake george up to 102MPH.. only once.. that was too fast.. but it would be nice to get this bogging problem fixed.. thank god, that Stewarts Shops sell plugs on the trail...

Ron
 

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Ron, when it is running good, how do the plugs look? They should be a light brown color. If they look black then it may be running too rich at the low circuit(idle). You may also have a bad fuel pump that is allowing fuel to go into the crankcase. Look at the hose that runs from your pump to the crankcase, see if there is any wetness in there.
 

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How does it start? 1 pull sometimes and maybe 10 pulls another. Does it start harder after its been warmed up? I have a friend that has a 91 skidoo formula that did the same thing last season. We took the carbs apart (all needles, seats, everything and cleaned well with carb cleaner and a old toothbrush. Put back together, reset mixture srews to earlier settings and wha la, sled ran great. I know that carb cleaning is brought up in alot of forums for a fix. But this is the heart of the motor after all. Even the float needle and seat could be leaking and letting gas fill the bowl overfull and running into you cylinders. This was what I went thru last season. If you have a nut at the bottom of the carb bowls, take them off and look. They should be spotless clean. If not, time for a cleaning. It only takes 3 months of old gas sitting in the carbs to leave a nasty grimmy film all over.
 

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Yeah, I sure sounds like either jetting, or airscrew setting.
Go to the Mikuni site (link below) and print off some of the tuning pdf manuals,
they really helped me with my old Trailcat.

This will take you to a troubshooting area, but there is a few good pdf's
to be printed off, I just didn't have time to find them for ya...good luck.
http://www.mikuni.com/fs-tuning_guide.html

Found one more...this should be for your roundslide carbs...
http://www.mikuni.com/pdf/vmmanual.pdf
 

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Check your choke setting to be sure the chokes are not being held partially open, and also may want to check the fuel inlet needles and seat. It is possible that they arent sealing properly and at idle, raw gas is just being pumped into the cylinders. Also is it just one plug fouling out? If only one plug is fouling out and it is the side that the fuel pump impulse line is connected to, then the fuel pump diaphram may be leaking and allowing fuel to flow through the impulse line and into the crankcase.
 

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Discussion Starter · #6 ·
OK, I will try to do this reply again... To Zackattack: This sled starts on 1 to 2 pulls all the time.. EVEN when it is running bad! both plugs are black, AND I have no Idea how they look when it is running good,, I ride at that point!

And to the rest of you all Thanks a lot,,, I guess it is time to do a carb cleanning ,, But what baffles me.. As I forgot to mention in my original question// It seems to do it worse when it is rainning or snowing? but nothing in the engine compartmnet looks wet.. just may be a kqinki dink???
 

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Discussion Starter · #7 ·
I am also wondering if anyone has ever seen an electric start on one of these bad boys,, i had it bored and polished and ported.. and now it takes me and my son to pull it to start it.. runs great,, but hard to pull, so I have 2 choices.. one is electric start, or some how put a compression release on it to get it started..
 
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