KX500 - how much HP and torque - Dyno?

[TexKDX]

Any of you KX500 riders ever have one on the dyno? What kind of HP and torque do they make stock, and what are the common mods to make them more ridable?

I'm considering doing a open area project bike and the KX comes to mind. I need to stick with the KX over the CR for reasons I cannot disclose, so please don't try to get me to change brands :cool: .

Thanks!

 

[RVL]

KX500 = 55hp
CR500 = 56hp
Search the archives for a dirt bike dyno shootout among many different bikes.
-RVL

 

[Buckholz]

I'd say RVL was about right on the dyno figures.

The KX will have better low rpm horsepower (torque....) due to the power valve.

I've desert raced both and owned a KX500 for three yrs.

 

[TexKDX]

As long as I have more HP and less weight than those ferries on the DRZs and YZFs...:p The 520 will still be a problem though. Better send it off to Eric Gorr for a re-work!

 

[Buckholz]

Stock KX500 has more power than a KTM520 in my humble opinion.

PS> for open (WFO) work, get the special FMF desert pipe, and add procircuit's copper base gasket and soften up the suspension, along with lacing up a 18" rear wheel.

Course, a KTM380exc is ready outta the box....

 

[Camstyn]

The CR actually has more low than the KX.. In fact, it has more low end than anything on the planet. Too bad it falls on its face at around the midrange mark.
The KX makes a nice controlled surge of arm stretching power from idle to redline. Like a rabid 4-stroke.:p

 

[Camstyn]

Originally posted by Buckholz
Stock KX500 has more power than a KTM520 in my humble opinion.
PS> for open (WFO) work, get the special FMF desert pipe, and add procircuit's copper base gasket and soften up the suspension, along with lacing up a 18" rear wheel.
Course, a KTM380exc is ready outta the box....

Whooaa.. make it softer?? I didn't know that was possible :P

What does the copper base gasket do? I had never heard of it when I had one. The optional thicker head gasket did help with the detonation problem that all KX500's seem to suffer from.

 

[Buckholz]

Copper base gasket - the big Kaw's have trouble with sucking base gaskets after prolonged WFO usage in the desert. ProCircuit geared up and ran a buncha copper base gaskets to get rid of the problem.

Stock compression valving on the KX500 is too stiff, and I was a 210lb expert desert at the time

 

[TexKDX]

Hey Buck, sounds like you have lots of experience with them.

What gearing will I need in order to get a top speed of about 110?

 

[Buckholz]

With dirt tires, on a long sandy road towards then end of a Mexico desert race at sealevel, I got radar'd at 99mph (ya I know) with a 16/43, basically laying down on the tank.

With my fat hind end, I didn't think my big Kaw would have pulled me much faster with taller gearing. A good port job would have helped the engine make more power at a higher rpm. My jug was stock

With stock engine internals, you would need 10% taller gearing to go 110mph, and I don't think a 17T front would fit very well, so you'd be looking at a 39t rear.....

 

[greenteam403]

horses

:yikes: I got my kx 500 3 years ago from a guy who pro ice raced all done by him 68hp at rear wheel one of a kind

 

[Colt891]

Im pretty curious what kind of power my Husqvarna XC500(cc) 2stroke will make compared to the KX's and CR's. Ive heard that its unrivaled in the desert. Its a great bike though

 

[99raptor]

I've ridden all of the big 2 smokers,,and the Kawi 500 is the real deal.I guess thats why they have like 10 Baja 1000 wins under there belt.

 

[jb_dallas]

I have read and heard first hand from a guy that owned a KX500 that the horsepower depends on the year. I thought the HP of the later models were closer to 62hp at the crank.