'03 Misfiring on Left

[Loki]

Alright I've been trawling this site for the last couple of days looking for someone else who has run into the same problem as I have. First off a little background info: I have an '03 shee pretty much stock standard 'cept for a pair of pipes, also i live in Australia so help and all that is far and wide (even from Yamaha dealerships... they know shit where I live).

 

I bought the shee about a month ago and it was running an it still does, no problem starting it up or anything like that. The problem lies with it misfiring on the left cylinder. Ive checked spark and it is there albeit a bit weak, I have a new coil coming this week. Fuel is getting there, just not being burned (tip of exhaust was saturated in unburnt fuel). Haven't checked compression out probably will later on today. I did take the carbs apart to clean em a while back but had no problem starting it after that. I read about puttin the slides in backwards and am going to check that today too it just doesn't seem to be a fuel problem.

 

Thanks for the help and sorry for the wall of text...

[flattrakker]

check for piston slap you could have a blown piston and its not burning the gas and its just blowing it out.. ive had 2 engines do this to me now. first up was my 20HP mercury outboard motor and recently my shee. id open it up and look at the pistons.

[swrbansheeboy]

Alright I've been trawling this site for the last couple of days looking for someone else who has run into the same problem as I have. First off a little background info: I have an '03 shee pretty much stock standard 'cept for a pair of pipes, also i live in Australia so help and all that is far and wide (even from Yamaha dealerships... they know shit where I live).

 

I bought the shee about a month ago and it was running an it still does, no problem starting it up or anything like that. The problem lies with it misfiring on the left cylinder. Ive checked spark and it is there albeit a bit weak, I have a new coil coming this week. Fuel is getting there, just not being burned (tip of exhaust was saturated in unburnt fuel). Haven't checked compression out probably will later on today. I did take the carbs apart to clean em a while back but had no problem starting it after that. I read about puttin the slides in backwards and am going to check that today too it just doesn't seem to be a fuel problem.

 

Thanks for the help and sorry for the wall of text...

 

backward slides will make your bike not want to start without holding the throttle open. doesnt sound like thats your problem from what you've said. i'd start by swapping plug wires from left to right and see if your problem switches sides. if so i think i'd be looking at a new set of plug wire ends and wires mainly because there affordable and it's a good idea to replace em every 5 years or so anyway. make sure all your grounds and the connections at the coil are clean with good contact. if it stays on the left cylinder then i'd be doing a compression test to see where your at. check that stuff and let us know what you found out...

[Loki]

Ok guys thanks for all the help. I fixed the problem but I don't know exactly what fixed it as I did a few different things to it this weekend. First of all I got my new ignition coil with new leads and plug caps and fitted that. I also removed the T.O.R.S system completely (I think the previous owner tried to do it but didn't disconnect everything, they only cut off the throttle clicker and nothing else...). I also clean out my fuel tank and petcock because it had a lot of mud around the two filters.

 

Now I'm just waiting on my Clymers manual so that I can give it a good tune and then I'm off to the dunes down in New South Wales!!!

 

Thanks for all the input.

[Lastman]

Great news, glad to hear it well for you.