[uniquebrett]

Last fall I rode my 02 650 with no problems... this week I fired it up and it would only run good above 4000 rpms. With the enricher plungers engaged (choke) it runs but not smoothly. It is like it never gets warmed up. it is ridable, but at low throttle speeds it is unpredictable...it stumbles and then when it kicks in you better be holding on. Does it sound like a bad gas issue ( I do not think I used any stabil gas treatment in this bike last fall) or does it sound as if my jetting is messed up....I have had this back rejetted to match the custom open exhaust. Any help helps.
Thanks

 

[evad4308]

Probably cummed up carbs if it was ok before you parked it.

 

[billbillw]

Sounds like the low speed circuit is gummed up and running too lean. Try some seafoam and see if things get better. Most likely you will have to tear down the carbs and clean them out.

 

[nokturnal]

yep, as others have said - gummed pilots.

 

[mighty9mouse]

Sounds like the low speed circuit is gummed up and running too lean. Try some seafoam and see if things get better. Most likely you will have to tear down the carbs and clean them out.

which is best? Pouring the Seafoam directly into the carb and letting it settle for a few minutes -or- mixing it with gas and running it through.

 

[2JZ]

best is pouring it in and letting it soak (and be prepared for a bit of smoke when you start her up again) but pouring a whole can into your gas tank, letting it run for a bit to get it through your system and then letting it sit overnight might be enough since it was working before (doesn't sound like it's gummed up that bad)

 

[2JZ]

Just for future reference, gas should always be stabilized prior to storage

 

[Zokambaa]

did mice make a nest in your exhaust can ?


it's been known to happen on occasion...


but yeah probably just bad gas.... or condensation in the gas... drain it, refill it with some seafoam (as mentioned above) or someting and see if it gets any better

 

[uniquebrett]

I think I will try to clean the low speed pilot jets....what is there location in the carbs? I am sure they will be accessed by removing the bottom cap off the carbs ( float bowl) correct? I just dont want to mess with anything that doesnt need tinkering with. I have a diagram of the carb but am unable to attach it.
Thanks
Brett

 

[Zokambaa]

I think I will try to clean the low speed pilot jets....what is there location in the carbs? I am sure they will be accessed by removing the bottom cap off the carbs ( float bowl) correct? I just dont want to mess with anything that doesnt need tinkering with. I have a diagram of the carb but am unable to attach it.
Thanks
Brett

just download the service manual... it will give you all the info you need...

I think this is one link to it....

http://www.repairmanualclub.com/motomanuals/index.php?dlid=503

or here if you don't want to sign up

http://www.carlsalter.com/download....117097108095039057057045039048049046112100102

 

[uniquebrett]

Re: Bad Gas or Jettining issue???...FIXED

Thanks for the advice and replies here is how it turned out-
last nite I added half of the can of seafoam and about 3/4 gal of gas...the tank was bout empty. I drove 32 miles at a low rpm where it was cutting out and running rough.....no change. I let it sit 18 hours...and then rode today...it ran about the same for 4 miles and then I turned around, by the time I was back home it was idling, but rough. I turned the idle up to about 1600 rpm and it was good... I rode agian a few miles, tunred the idle back down and it seems to be fine. I then rode the way it should have been all along...yep I should have added stable last fall....I appreciate your help.

Have a good ride guys.
Brett

 

[Zokambaa]

Re: Bad Gas or Jettining issue???...FIXED

If your tank wasn't full when you put it away and it is not in a climate controlled area then you probably have condensation in the gas... once the water is out it should be fine I know it could be spooge in the carbs from funkified gas, but my experience with carbs on an old bike when I did not know to put stabil in the tank over winter tells me it is more likely water.... unless you don't ride it for 6 months or more degrading gas probably wouldn't be that obvious... a little water in the gas will be a problem

some may say I am wrong... but I had an XS 400 and I never put stabilizer in it... but I always gave it a full tank before putting it away for the 4-5 months of ice.... but I guess gas can go bad in as little as couple months

I'd bet if you had drained out all the gas and put in fresh it would be fine too...

and if you put stabil in a 1/4 full tank, you could still get the condensation. but I berlieve sta-bil now has a drying compound in it too so perhaps that wouldn't be an issue.. I believe seafoam not only removes moisture in the gas but cleans too so it's hard to say what the exact cause was here..

But as mentioned... if you aren't going to ride for a few months... toss in the sta-bil fill your tank fully and you're good.

Thanks for the advice and replies here is how it turned out-
last nite I added half of the can of seafoam and about 3/4 gal of gas...the tank was bout empty. I drove 32 miles at a low rpm where it was cutting out and running rough.....no change. I let it sit 18 hours...and then rode today...it ran about the same for 4 miles and then I turned around, by the time I was back home it was idling, but rough. I turned the idle up to about 1600 rpm and it was good... I rode agian a few miles, tunred the idle back down and it seems to be fine. I then rode the way it should have been all along...yep I should have added stable last fall....I appreciate your help.

Have a good ride guys.
Brett

 

[KB1]

I had the same problem when I bought my 99 a few months ago. The guy let it sit with 1/2 a tank in it all winter. It smelled like turpentine. He had to clean the carbs and it took a 1/2 tank of new gas to get it all cleaned out and running well. I'm interested in this sea foam stuff though!!

KB