When the engine is cold, it is almost impossible to start. With choke...without choke...with throttle...without throttle...everything I can think of. In fact, I've taken to pull starting it and then it fires just fine.

Is there something I'm doing wrong?

 

ran into someone the other day with the same problem...thought maybe his starter wasn't spinning it fast enough, but it spins twice as fast and easily as my raptor...I suggested he check his valve adjustment and go from there...

 

Peoria, huh. I work in Peoria.

Anyway, take off the air filter or air filter hose, cover the carb with your hand and try it then, It worked for me.

 

I agree with RAPTORJAY....sounds like valve adjustment time.

 

If I remember correctly Bomb changed the starter jet in 01 due to this problem. I'm not near my shop manual to check it, but it could be verified by the dealer's parts dept. In the meantime, just shoot the air filter with a shot or two of starting fluid. Another thing to try is to loosen the gas cap when starting it cold. If the tank is too full of fuel or the vent hose is pinched under the tank cover it will create a vacuum in the tank that won't allow fuel to flow to the carb.

 

Thanks to everyone that replied to this post. I adjusted the valve clearance and it starts as soon as I touch the starter button. Unbelievable!

Story of the Valves:

The manual lists the intake and exhaust clearance as 0.100 to 0.150 mm. I could fit a 0.006in (0.152mm) feeler gauge under both exhaust valves but not a 0.007in (0.178mm). The intakes had no clearance at all, not even the 0.0015in (0.0381mm). The exhausts had 2.35mm shims, the intakes had 2.45mm shims. The shims are labeled but most of the label was worn off. I took them to work to measure them, but any reasonable caliper will work.

None of the Bombardier dealers near me stock the shims and them want from $8.95 to $11.00 to order them (each!). I went to a BMW dealer and not only did they have them in stock, but they charged me $2.99 each.

I replaced the exhaust with 2.30mm and the intakes with 2.35mm (from the exhaust). The exhaust clearance went to 0.005in (0.102mm) but the intakes still had no clearance. Unfortunately the BMW dealer didn't have a full stock so I had to try 2.10mm. FINALLY some clearance, but it was too big. Luckily the clearance on the left and right valves was not equal, so I used a 2.15mm and 2.20mm (which they had) and ended up with 0.152mm and 0.178mm clearance. One is at max. spec and the other a little beyond, but they didn't have 2.25mm and 2.30mm shims, so I stopped.

Like I said before it started immediately, no more degrading pull starts.

The procedure for adjusting the valves is pretty simple. The Rotax is a terrific design with reusable rubber gaskets instead of metal or felt. The more I work on this quad, the more a appreciate it's design. I've had a 400EX and a Banshee, and as nicely put together as the Honda was, the Bombardier is better. (as far as the Yamaha...it's real fast but not great mechanically)

Thanks again for all the help.

 

Glad to hear such a routine fix solved your problems. I'll have to keep that in mind if mine starts to get even worse about starting when it's cold. How cold is cold in Arizona?

On Saturday I went riding when the temp was about 25 out. I did manage to get it started eventually without resorting to the hand-choking (with the air filter off) method, but I always keep a screwdriver handy.
For others who read this that might try the starting fluid method- it works, but don't use much. (at all) I used it once and had a little backfire that started an impressively large ether fire. I kind of think of ether as a last resort now, at least for gas engines.

 

Anyone have a pic of the valves? I don't have my ds650 yet but someday I'll have one and I'll want to do this stuff myself. I hear people talking about doing valve adjustments all the time and try to imagine it but I think I need a visual aid [img]i/expressions/face-icon-small-smile.gif[/img]