Problem with 03'wr450please help

[dbone]

So I was riding home from school last night doing about 55mph and out of nowhere bike started to misfire.As per the "stutter gone" post a few days before that I unpluged the TPS and the bike ran great for three day,better than it ever has.I stopped on the side of the road pluged the TPS back in and it did great the rest of the way home which was only about a mile.It fells like a firing problem,it seems to go in and out kind of like a misfire.I change the plug,the one than was in it was nice and tan looked good,and still the same problem"misfire pop pop stutter stutter".Could it be the CDI if so how would I check it?I've had it for about three months it has run like a champ.Please don't know what to do or where to check. Thanks,

Dbone ?

[Indy_WR450]

You may be rich on your jetting. You should be on a 160 / 155 main for your temp in AZ with JD red #4 needle postition ?

[luke_n]

So it ran fine right after you plugged the TPS back in?

I have two rides on mine now with it disconnected no problems yet.

Have you unplugged it again to see if the misfire comes back?

[dbone]

I did plug it back in and it ran fine to get home,but this morning it was running like crap.It feels like a misfire,or as if it is missing,it will idle.When I twist it throttle it starts to crack and jolt,it will go in and out.Does not feel like a jetting problem.I'm running stock jetting,and it been runnig great until now.I keep thinking that it may be a connector that has wiggled lose.I'm going to tear it down in the morning and inspect all wiring...Is there a chance it could be the CDI or coil...

Indy,

Did you get my letter...

Donnie

[Brettv]

i had a similar problem with my 99, it would run like crap and sputter and miss, all of a sudden without notice.... my problem was BAD FUEL. did you fill up somewhere dodgy? i drained the tank and bowl, put new good quality fuel in and she started right up and was fine.

hope this helps

cheers ?

[dbone]

Man, now your on to something.I put gas in just before this all started.I'll check that in the morning...Good idea..

Donnie

[dbone]

Well drained the gas this morning,no change.I will pull the coil and take it to school tonight and test it.If it's good I'm to go over to the YAMAPRO classroom,and talk with one of the instructors and see if unpluging the TPS could have caused any problems with the CDI.Wish me luck!

Donnie

[WR450F_RDR]

I have always been told not to unplug the TPS unless you are replacing, something with the unit needing to be set precisely in order for it to work, I guess there is a special tool to set it? had a friend go thru a similar problem with the TPS and a WR250.

[dbone]

Here's a thought could it be the woodruff key problem.Maybe it sheared but the rotor only moved just enough it throw it out of time.I'm going to pull the rotor tomarrow just to get the thought out of my head... ?

Donnie

[5spoke]

Did you drain the gas from the tank and carb? I doubt having the TPS unplugged would mess up the CDI all of a sudden, especially after you'd been riding without it for a while. I would think you would either have problems immediately or none at all. Keep us posted. ?

[5spoke]

Here's a thought could it be the woodruff key problem.Maybe it sheared but the rotor only moved just enough it throw it out of time.I'm going to pull the rotor tomarrow just to get the thought out of my head... ?

Donnie

While you in there, check the pick up coil.

[dbone]

5spoke,

I would tend to agree with you,I think it would cause a problem right off the batt.What do you think about the woodruff key deal,if it was out of time just a very little bit it could make it snap crackle and pop when I twist the throttle.It will start and idle but you can hear it miss every now and then?

\Donnie

[gomopar440]

I had a similar experience yesterday on the ride home from work. I got the "snap, crackle, pop" and the bike started to cut out on me. I had read this post right before I left work so I was thinking I might have messed up my CDI or something. I did a quick scan of the GPS and noticed that I had 100mi on this tank so far ?. I guess all the wheelies kept dumping the fuel back towards the petcock . Any way I reached down and turned the fuel to reserve and it cleared right up. So, if a lean fuel situation is causing the "snap crackle pop", I would start by checking the petcock and fuel line for blockage. If that checks out try checking the float level and the needle and seat. You already checked for fuel contamination but it wouldn't hurt to check the bottom of the tank and float bowl for any residue from anything (water, rust, crud)that might have passed through it.

[5spoke]

5spoke,

I would tend to agree with you,I think it would cause a problem right off the batt.What do you think about the woodruff key deal,if it was out of time just a very little bit it could make it snap crackle and pop when I twist the throttle.It will start and idle but you can hear it miss every now and then?

\Donnie

I doubt the WKey can bend just a bit. There is just no room for it to move. It will either be intact or sheared off. It's worth a look.

Are you sure it's not gas/carb related i.e. water. How did you drain the gas? Did you take the tank off and flush it out a few times? Did you remove the cap under the carb and check for deposits? Check jets etc. ?

[dbone]

Problem solved,wires coming out of stator must have been caught by something moved close to exahust and were getting very hot.Moved wire away and checked for short,replaced heat shrink took for ride,runs like new.Thanks to TT I didn't freak out and take it to a shop.Thanks to all.

Donnie ???

[simch]

isnt the stator wiring the other side to the exhaust??

[Lowedog]

Could this be a result of unplugging the TPS? Unless you rerouted the wires I don't think they are close enough to the exhaust to get that hot.

Lowedog

[dbone]

The problem was stator wires,yes they are on the other side of exahust.I think something came up and hit them because the zip tie was broken.