JUST ANOTHER 2016 KTM 250SXF CHASSIS KX500 ENGINE CONVERSION GONE MAD!

kxguru@bikerider.com
You can find me on Facebook:

https://www.facebook.com/groups/179257569231617/

Or at my web forum

http://www.kxguru.com/ where I have a bunch of kx500 specific info.

No worries... I appreciate any positive advice.
Remember, no matter where you are at, you can always learn new things...
And I want to learn everything good

I had to show you guys this...
It was a total shocker as we had no idea MXA was doing such a thing.
I'm glad to see that we made an impression.

Motocross Action Incredible Two Stroke Hall of Fame
THE BEAST!!

I finally got my Cerakote gear set up and decided to try some color.
So what better part to try it on then my back up 2 piece clutch cover..

Thanks guys, yeah, development on the big K5 didn't really stop it continued on at KXRiders and KXGuru but since we built Sean's bike a couple of years ago things really have taken off. Hopefully guys will continue taking what we love and making it better. Speaking of which I have a Turbo crank set up in my Supermoto and we are tuning and testing. I will have some comparison dyno number sometime next week...

I have some dyno results for a KX250 here:

KX250 Turbo crank

In short 7HP in the mid range and 5 on the top.
And that is with a worn out engine and fine tuning left to do
We will be doing several mods and yes, a new top end.
And we will be running each mod on the dyno to see what we gained or lost.

Here is a link to the KX500 Turbo crank testing:

KX500 Turbo Crank

Well... first let me say that Steve Parris told us about what we should expect for power delivery... 15-20%.
I have to admit.... I was very skeptical...
But, we got 20% in the mid and 15% on top...
Don't run out and buy a Turbo Crank... First, they are not all created equally and second we are still testing.
But I have to admit, at this very early stage of testing, I am very impressed.

Jetting wasn't bad but we had to put aside much of what we know about jetting a naturally aspirated two stroke and keep pushing it leaner. Steve Parris told us that we would be shocked and we were.
The starting jetting looks coco brown and we thought perfect! Whoa, can't believe it... But no power...
So down we went a step at a time. We gained a little power each time but the color never really changed.
After about 2 hours and many jets swaps we lost power.
We checked the plug and it was a little more grey then before, so we backed it off one step and 5th gear wheelies happened again
We still have some needle work to do so I think we may get a little more mid range but I think the top end is as good as we can get.
Monday morning we are headed to a high tech dyno to verify what we recorded at the older dyno.
After all, why not verify :-)
So testing and tuning will continue to see what happens.
But at this moment... I have good feelings about this.

Take a look here:

1998 KX250 Turbo Crank Build

7hp in the midrange and 5hp on the top end

Lol... Not everyone is old enough to know who that was...

Who is EC Birk?

I hope you paid good attention to what he had to say...
I've had some awesome mentors over the years and still looking for more

Which RM? Both are pretty nice.
And did you build it?

OK... Since I'm not sure we will be able to figure out why the turbo crank worked so well in the 250 and not the 500 in time for this build I'm starting a new crank...

Before..



During..



Almost done..

So far, the 500 lost about the same amount of power that the 250 made
But... we have many things to try to improve the performance.
We have not tried any mods as of yet but we will in the near future.
We are not giving up on it but it will take some time to see if this mod is viable on the 500.
On the 250 we haven't done anything more other then ride it.
Mid to upper power range is lively
The bottom to mid has more torque.
The next step will be to replate the cylinder and put a new piston in it.
Then, run it on the dyno again.
We believe that with some more testing and tuning we should be able to make some more gains.
I'll keep this thread up to date as more info becomes available.

Double checking final fitment..







Everything is lining up so we are very close to disassembling and powder coating...

Oh yeah... I just got this TSR cover back from the Anodizer.
Looks sweet..



I had to try a green one as well..

Ok... Finally, it's ready for some touch up welds, then off to sandblast, and finally Powder coat..
Unimpressive to say the least but it's a big step forward..