809 rotax runs fine then falls on its face??Help

[Rowdy1132]

Selling this sled and took it out for a test run, Starts fine, idles. Get on it hard, pulls great then falls on it face, like it runs out of fuel or out of spark. Does it all day. It's an 809 in a king cat chassis. It has a mikuni standard 3 cylinder fuel pump, do these need high volume pumps? Also has stock rack carbs. I'm sure it simple, but getting very frustrated, please help....thanks

 

[freekweet mods]

What kind of air filters? K and N's may look clean but still might be clogged enough to choke engine at WOT.

 

[Rowdy1132]

Kick azz, thought that too, so took them off to try it, same same.

 

[flying pig]

Starter curcuit stuck open? sounds a lot like its freezing up. maybe a bad coil could do it too. Do they have 3 coils on 809's or just one? Can't remember...

 

[Rowdy1132]

has 3 coils, so you think it needs a new stator? What would cause a sled to eat stators??

 

[freekweet mods]

I believe the stator has two ignition coils a low speed and a high speed this could be your problem . This stator can be tested with an ohm meter.

 

[Rowdy1132]

Could be it, i have a ohm meter, exactly how do you do it??

 

[JROD]

I've got another fuel pump for that sled if you end up needing one

 

[LRD]

Here is an odd one, had it happen and it does just what you are experiencing.
The spark plug caps should ohm out at about 5000 ohms. Had both go bad on an old phazer in the early 90's on a trip to Cooke. No power, fell completely on its face, they ohmed out around 25,000 to 30,000 ohms.

Have never had it happen again, have no idea why it did happen to both caps.

Good Luck

 

[flying pig]

unless the fuel pump is shot it won't b ur problem. We have ran them on triples up to 1500cc in deep snow big hill situations n never had them be short on fuel.

 

[Rowdy1132]

got her fixed, just a kinked fuel line when it got warm, thanks abunch for the help....