hello all, new to this and i have a question already, does any one know why my kvf650 runs fine on tick over but if you hold it at a steady 3500 rpm ish after about 15 seconds it seems to drop off on one of the cylinders and the front exhaust starts to glow red well almost white actually so obviously i turn it off , i have put new plugs in and borrowed a carb balancer and set the carbs hope some one can shed some light on this thanks for taking the time to read my essay. popey

 

sounds like a jetting problem, or maybe just a lack of fuel from a clog, pull the carbs and clean them really good, and while your in there check you jets

 

Im not any brute force expert but it sounds like your bike is running way lean and it needs to be re jetted and you need to go smaller on the main jet and maby shim the needle on the carb for the front cylinder.

 

Popey,
Everything you describe tells that you have very lean carburetion and front carb. By the way, most Kawi's V-twin carbs have different settings (lean front and rich rear). It seems it is lean at the midrange. The best way is to shim the needle jet on the front or install the same P/N of the rear carb needle jet on the front. This will take care of your problem. If not completely, experiment with a fatter main jet one size up at a time.

 

thanks all for your help i will give what you say a try and get back to you as to the outcome thanks again popey

 

hello well i seem to have cured the problem with the 650 dropping off on a cylinder on mid revs the rear cylinder cam chain tensioner was solid wouldn't move out under load from the spring and the front cylinder one would move backwards and forwards the little spring on the latch has broken on that one so i put in two new ones and hey presto its working spot on again thanks to those that replied POPEY

 

Glad you solved the problem. It sucks having broken parts floating around inside your engine. Fortunately you were able to fix it before it did any major damage.

I know a guy who had an 01 650 Prairie with very low miles (about 100 or so). A few months ago a snap ring came off inside his motor and pretty much destroyed it. It was a nice Quad, he only used it in the snow to tow his kids around on sleds. If I had the money I would like to get my hands on something like that and put a 750 BF motor in it. The 01 Prairie seemed to have a little smaller frame than the later models, at least the CG seemed to be a little lower. Something like that with a 750 BF motor in it would make for a very wild ride!

 

Did not know they made an 01 Prairie 650[img]i/expressions/face-icon-small-confused.gif[/img]

 

Maybe it was an 02 I don't remember for sure. I have an 04 and it was an older model than mine but with very low hours. It was in pristine condition until the engine failure. I felt sorry for the guy.