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Discussion Starter · #1 ·
98 RMK 700. i purchased it knowing something was wrong with it. the guy i got it from didnt know much about the mods as everything was installed before he bought it. this is what i can see on it so far....

SLP BOOST BOTTLE
HOT SEAT HEAD
GUTTED AIR BOX
STOCK PIPE
AFTERMARKET CAN (took it off, but cannot see a brand name on it)
STOCK CARBS KEIHIN PWK’S

-JETTING- (im not sure how accurate this is, but its what was installed when i purchased it)

i am at 1500' ASL
175 MAINS
42 PILOTS
R1371G NEEDLES

i have cleaned the carbs and made sure the jetting is the same on both carbs. the compression on both sides is right at 125. watch the videos of my egt gauges. you can see it is 150-200 degrees cooler on the LH side compared to the RH side. this temp difference stays consistant throughout the RPM range. it even gets a little more than 200* difference at 3/4 throttle to WOT.

something else iv noticed..... it will not run solely on the LH cylinder (while the RH spark plug wire is unhooked). it will pop a couple times and try to stay running, but it wont. however, it will stay running solely on the RH side while the LH spark plug is unhooked (obviously it runs rough because its on firing on one side, but it does stay running)

so, whats going on with my LH cylinder? any ideas? i just bought this sled and dont know a whole lot about it.....or it's history. when i 1st brought it home it wouldnt idle without fouling plugs. iv played with the carbs and it seems to be mostly over that problem. also, if anyone knows anything about the hot seat head, any info is appreciated. i see they have 3 different heads on their web site, but i do not see any markings on this head to signify which one it is.

at an idle




1/4 throttle

 

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When I had my 97 RMK 700, I had staggered jetting with the MAG side one step bigger. Are you referring to the Left as the PTO side? If so, check the plugs. If the PTO side plug is dark brown or black, you can safely jet it a size smaller. It's very common for the MAG (right) side to have one step larger jet. The MAG side cylinder gets heat soaked by the pipes, the extra fuel helps keep the air/fuel mix safe.
 

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Discussion Starter · #3 ·
i pulled the plugs this morning and peaked inside down at the pistons. the side that is running COOLER has a darker color on top of the piston. i wonder if its using water... thus it is cooler on that side (not fully combusting) and thus it will not run solely on on the LH (cooler running) cylinder.

or is the spark going to that cyl not not enough? is there away to check the output of the coil to see if it is within spec?
 

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If you were burning coolant, you would have a lack of carbon build-up on the piston crown, the coolant would be turning to steam and cleaning everything. You will also have a distinctive smell to the exhaust and loss of coolant in the recovery bottle.

If it's electrical, check the wires from the coil to the plugs, sometimes they will become a problem. If I thought it was a problem, I would change out the plug end caps and replace those with one-piece NGK ends. The plug wire ends unscrew from the wire. When replacing, snip a little off the end of the wire to make sure the new caps get a good contact. It could be you have too much resistance at idle, but when the voltage increases with RPM, the increased current overcomes the resistance.

Do you have an in-line spark plug tester? If not, pull that plug, ground it away from the spark plug hole and pull the rope. What is the quality of the spark? If you have a yellow spark or no spark, it's an electrical issue. If the spark is nice and blue, it's not.
 

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Discussion Starter · #5 ·
checked the spark with an inline tester. spark looked to be the same from side to side......but just to be sure i pulled a coil/plug wires off of my buddies 99 700. nothing changed. still wont run solely on the LH cyl, but will run solely on the RH cyl. im just not getting good combustion on the LH side, but i dont know why. im thinking this has to be the largest of my problems
 

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Discussion Starter · #7 ·
Try switching carbs side to side to see if the problem follows the carb?
you know.....out of all the brain storming i have done, i have not thought of this simple task lol. are the both identical? they looked very similar when i had them apart for cleaning and inspection.
 
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