I bought my 2001 DS650 a few months ago and heven't have much luck keeping it running. I posted once before with basic the same problem I'm having and did with was suggested and got it fixed but the problem came back. The quad was running perfectly fine for the last 2 days but today it started acting up again. The problem is that the quad starts fine and idles good but when I open the throtle up it bogs down and dies. This the same thing it did a couple of months ago and I replaced first the rectifier which didn't help and then a new battery which seemed to take of the problem until today. I checked for spark and it seems OK. Any one has any ideas or have experienced the same problem?

Thanks,

Ed

 

Although I've never had a CDI box go out on a DS, I've gone through plenty on my EX. So, I suppose thats a possibility.

 

Did you change the plugs recently? Did the weather change? It almost sounds like you are going way rich when you start putting a load to it......

 

Check the cam chain tention if it is out of timing it will do that same thing you are talking about, so it could be all that is related to the valves and cams. But the tentioner is the first place I would look because it is the fastest fix. Then I would check the valve lash.

 

id go simple first.....obviousy you have spark...your getting fuel because it idles...but once you rev it up it dies....anything aftermarket done to the carb, jetted??? check your float height, if that float doesnt open up enough to keep up with the fuel needed to run at higher rpms itll die...this happened to me when i jetted mine, i just barely tweeked the arm and it messed it all up...theres a post on here how to check it but its really trial an error, small adjustments...............also check for dirt or other crap in the bowl and check the diaphram in the carb, any holes in that wont allow the slide to open................what color are your plugs are they wet or black or a nice golden color???? trial an arror....but if your need parts let me know, im parting out mine

 

<div class="FTQUOTE"><begin quote>Originally posted by: matts01ds650

id go simple first.....obviousy you have spark...your getting fuel because it idles...but once you rev it up it dies....anything aftermarket done to the carb, jetted??? check your float height, if that float doesnt open up enough to keep up with the fuel needed to run at higher rpms itll die...this happened to me when i jetted mine, i just barely tweeked the arm and it messed it all up...theres a post on here how to check it but its really trial an error, small adjustments...............also check for dirt or other crap in the bowl and check the diaphram in the carb, any holes in that wont allow the slide to open................what color are your plugs are they wet or black or a nice golden color???? trial an arror....but if your need parts let me know, im parting out mine</end quote></div>

Haven't pulled spark plugs yet but checked the bowl and didn't see much. The strange thing was the thing was running perfectly fine just 2 hours before and the entire day as well as the day before. It set for a bit and started acting up. Nothing done to carb. I might take the thing apart and clean it up. Any other ideas would be apreciated.

 

I would go back to checking the battery again. The DS needs a good full charge in the battery to advance the ignition. It will idle all day with a half charged battery but will not rev up - it will just fall on its face. Try charging the battery overnight and see if the problem still happens.

 

Thanks for the tip. I'll give that a shot although I still don't understand why the quad ran perfetly for a couple of days and started acting up, is the battery not been charged for some reason? If that's the case what could cause the battery not to charge as I ride the quad?

Thanks,

 

The quad would run ok until the battery drained down. I have had the same problem - check the battery cables to see if they are loose. It could be a bad battery as well. I know I went threw 3 batterys.

 

I checked connections and everything seemed OK but I went ahead and tighten everything again just to make sure. The battery is about 2 months old so it should be under warranty, I'm going to take it back and see if they give a new one.

Any particular brand I should ask for?

Thanks,