hello all, this is my first post here in these forums, but you all seem very helpful here. So, I will try my luck. First off, I am a mechanical Idiot. I will not sugercoat things...lol I recently got a 2000 DS650, and everytime i have ridden it, after about 2-4 hours, of trail riding, and the ocassional opening it up on a dirt road, it will sputter and backfire unless i let off the gas almost completely. the other day it only took about a half hour to start doing this. but after a couple minutes of waiting with it off, it ran fine again. i checked both plugs and they both seemed to be fine as far as how they are burning, but the inner plug was hand loose, and the gap was almost completelt closed off. i cleaned them both and re gapped them. but haven't had time to ride it again since i did this. if anyone can help an idiot out with this problem, it would be greatly appreciated...thanx in advance for helping........

 

Man thats a tough one, and I will only be guessing here. If it takes some time to make this happen, then it happen when its heat soaked. So I will guess a couple things. First, if the plug was loosed enough, it could be causing a lean condition, and that would make it sputter if bad enough. If its backfiring through the exhaust, that isnt likely. Backfiring through the exhaust is usually a rich condition I have found. Are you making sure you turn the choke off? It might be stuck on.....? It really sounds like a rich condition, like its really loading up.......?

Anyone else got any ideas?

 

Just a thought here..........

Letting the motor sit for just a couple minutes will not be long enough for it to cool any. It will actually get warmer in the 2 minutes after it is shut off. That makes me question whether it is a carburation issue or not.

I would check the grounds to make sure they are good. One other thing.......I have seen weak spark simulate a rich condition so i would definitely test the bike now that the plugs are like they should be................I would actually replace them just for fun and make sure they are snugged. That may just do it.

It gets harder to test after this[img]i/expressions/face-icon-small-wink.gif[/img][img]i/expressions/face-icon-small-smile.gif[/img]

 

I'd check the vent hose on the fuel tank if it continues to spit and sputter after the plug work. When it starts acting up loosen the gas cap up to let air in, if it smooths out your vent hose is pinched off. If the vent hose is plugged as fuel is used from the tank it will draw a vacuum in the fuel tank and restrict fuel flow. If you find this to be the case you can pull the tank cover and replace the vent line, or plug the line and install a vented gas cap. Keep us posted, Mech.

 

"after about 2-4 hours, of trail riding, and the ocassional opening it up on a dirt road, it will sputter and backfire unless i let off the gas almost completely. the other day it only took about a half hour to start doing this. but after a couple minutes of waiting with it off, it ran fine again"


Sounds like and question for azsand. He has had electrical issues like this.[img]i/expressions/face-icon-small-tongue.gif[/img]

AZ can you help this man?


Sorry I couldnt resist.

 

to me it sounds like a few small thing into one the plugs I would think have a great deal in the problem you have here...The other is something with the carb and it seems like you aren't getting enough fuel at certain rpm's what do you have done exactly any jetting or any of that...is the airbox lid on or off...make sure the head bolts on the header are tight becuase if they aren't you could be lettign cold air get into the hot exhaust and itll backfire I just replaced my gaskets and got new bolts and hasn't backfired since...If you are capable of taking the carb apart if it is still running bad clean the jets out and check the diaphram which is the top part of the carb that holds the needle and make sure it is sealed right and there aren't any tears and also spray some wd40 on it. Hope this helps.
Brett

 

I'll thow in my .02... I think Mechanicsm is right, I would be leaning towards the vent. When it happens again try cracking the gas cap... if that helps then get a vented cap.

 

yea fat you are right I would check the easy stuff like that first i had a problem with my cap it was so air tight that gas was coming out of the overflow in the carb.

 

LMAO............Are you gonna let him call you Fat? I will never forget when supersonictoys honestly thought Fatholly was a fat chick![img]i/expressions/face-icon-small-happy.gif[/img] ROTFLMAO

Oh........Sorry[img]i/expressions/face-icon-small-blush.gif[/img] Carry on with the topic[img]i/expressions/face-icon-small-wink.gif[/img][img]i/expressions/face-icon-small-smile.gif[/img]

 

I cannot deny what I am LMAO... besides I've been called worse... back in elementry school I used to think my name was fat boy... its all good.

The chick thing though still makes me laugh... I swear if I saw a chick that was my size I would **** my pants, then run and hide. You just don't see women that are 6'6" and 350 lbs... I'm just looking for a nice young lady that is over 6'2"... I call 'em breeders... I want to pop out some 1st round NFL draft pics... thats my retirement plan.[img]i/expressions/face-icon-small-happy.gif[/img]