I have an 01 DS650 that I bought from local wholesaler and at the time that I bought it the battery was dead, but he claimed it ran. I have bought a few machines (20 +) off of him and he usually is very up front on what needs fixing.

Anyways I installed a new battery, drain the gas, clean the carb and installed new plugs and tried to fire it up. It would start then die right away, I thought maybe it was not getting enough air so I installed a new air filter and that did not help. After playing with it for a few minutes I discovered that if I held in the start button it ran awesome. I'm guessing that it's an electrical problem, but I'm not sure where to start. I would like to know if anyone out there has had the same problem or if someone could help steer me in the right direction.

Thanks For Your Time,
Jay

 

Can you do a compression test? The valves might need some serious adjusting and the starter is aiding the motor just enough to compensate for a lack of compression. Just a thought.

Ron

 

Sounds like a ground problem. Check the main ground at the frame that comes off the battery

 

Without a schematic in front of me I can only theorize here but I suspect that its the ignition module,
Most modules have a run circuit that only activates during start mode and another only for when the starter is not enguaged, as is normal run mode.
I have not heard of this problem with the DS before but I have seen it on other engines. I could be way off here so don't go out and buy one without maybe trying somebody elses first if that is a possibility. Unless you just want to upgrade it.

 

JSsDS,

That is a hell of an idea! Maybe someone in the "Whats in your Garage" thread has a stock cdi for cheap. I bet you are right.

Ron

 

Hey offroad, I don't know if this helps but I had this same problem when I put my ds together. I think my problem was caused from trying to start my ds with a battery charger. I did not have a battery in the quad at that time and was only using a charger and had the charger in the boost position. I could not find anything else wrong with it so I assume the problem came from that. When I tried it with a car battery it fired right up with no problems. Since then I have installed a new battery and it has been fine every since. So I don't recommend using a charger in the boost position to start a quad. A charger puts out alot more voltage than a quad wants, so I only use a charger to charge a battery now and let the battery do the work. I hope this has helped and if not I wish you luck. I also posted about this ahwile back and posted what I found. So if you find out the problem or what you think the problem was, post it so we all have that info available. RUSS

 

rfwll ... i was working on a ds that did the same thing we couldnt figure out what was wrong "trying to get it to run before replacing the battery" then replaced the battery and boom fired rite up i would definately try that first

matt