97 rmk 700 doing some funny things

[miralas]

i'm getting a buddies sled ready for him for when he comes back from his deployment and it was doing some things that i dont know the answer to.

first i went to pull his sled off a trailer after i rode it all day and noticed that it was sparking under the hood when i hit the throttle, but didnt seem to be coming from anywhere specific. i only noticed it because it was getting dark. it doesn't have a battery of any kind so i wasnt sure what could be shorting, or if there was actually anything shorting.

next i went to start it yesterday and it made a couple bad back fires, ran poorly for about ten minutes then cleaned back up again and ran awesome. it didnt do that the whole day i took it out for a "reliability test"(my reason for taking out my buddy's sled ). i should know this and i know its probably just something to do with crud in the fuel but i would like to get a more accurate answer since i'm not very good at recognizing what bad sounds mean from an engine. thanks for your guy's help.

 

[retiredpop]

Sparking is probably an indication of bad spark plug wires and/or boots that need to be replaced. As far as the backfire goes I wouldn't worry about it. You just need to let it warm up before driving it. The 97 did not come with a thermostat so it takes a while longer than normal for it to warm up.

 

[miralas]

thanks for that info. as soon as i'm done resurrecting my dragon i'll put a little money into to that and get this thing running new for him. this was the first old sled i've ridden and it was a blast last week when i took it to the mountains. if i cant get my POS fixed i'll probably drag it to the woods, roll it through some trees, claim it on insurance, and buy 4 of these things.

 

[jsledder]

Wouldn't hurt to check the reed valves, I've got a couple of those motors and both have encountered the backfiring for whatever reason and they've both shattered the reed's during that time.

But, those are great motors!!

Does it still have the Keihin carbs or has it been converted to the Mikuni racks?

 

[miralas]

i'll have to look when i get a chance but i think the only engine mod on that sled is a power dome and maybe some clutching. i remember i was goin to redo his carbs for him this fall and everything looked right from the online part manuals i saw, so i would say they r the stock carbs on there.