KDX200SR top end differences

jaguar · Feb 21, 2003

Looking through the posts I saw that there was no agreement as to whether the SR (int'l model) and R shared the same top end. Looking up the part #'s at http://www.kawasaki-motors.com/parts_cat/parts_mc_kmj.html for the SR, and http://www.buykawasaki.com for the R, I saw that the head, cylinder, base gasket, and cases were different. So now I need to get a degree wheel and see how different the port timing is.
Here's the part #'s:
Part SR R
----- --- ---
head 11001-1301 11001-1291
piston 13001-1290 13001-1295
rings 13008-1110 13008-1116
cylinder 11005-1585 11005-1569
base gasket 11009-1817 11009-1994
cases 14001-5264 14001-5262
Looking up the SR parts costs at www.bikebandit.com I saw that the head, cylinder, piston/rings, and cases were not available. So they'd have to be gotten from the UK (contact corby.kawasaki@btinternet.com) although I have successfully used regular R model piston/rings and base gasket.
Also the SR has a thermostat on the head that the R doesn't have. I'd guess for competition use the SR should have the thermostat removed/replaced with the gasket of the R model (#11009-1993).
My bike runs pretty strong but still not as strong as a normal KDX. Now I know why.

B · Feb 22, 2003

By the way Jaguar, The SR parts are pretty expensive here as the SR has only been imported in small secondhand batches. Theres tons of them too. The temp sender is priced at 58 UK pounds. Dame pricy if you ask me. mines on the blink so if anyone has one to let go, let me know. Ive also been trying to locate the regulater (well thats what I think it is) that sits just behind the right hand radiator. Its just a big ceramic resistor. It was snapped when I powder coated the frame and now my indicators keep blowing. I fitted another from some old suzuki but as my old one was in pretty bad condition to start with, I was never able to check the Ohm value.

I alway thought that the timings where pretty close but as standard they are down 3 or 4bhp. I used to work at a 2 smoke tuners and he had all the Kawasaki 2 stoke spec books. The first time he saw my bike he happen to say 'thats the weakest of the two models' at which point he got out the books. They didn't look that different but the intake is different. the 28mm carb makes quite a difference. The airbox book is narrower too.

Ill ask to see whether I could get them of him to post somewhere.

B

Cheers B

jaguar · Feb 22, 2003

So did you attempt to have yours ported to match the R model? I'll try to dig into mine and measure the big resistors value. What have you done to yours to up the power?

B · Feb 23, 2003

I did the pipe mod, new reeds (tried both low tensi and single stage thick boysen's), had the head skimmed and generally keep her in good nick. The first time I stripe the motor I lapped and polished all the cylinder ports together so everything flows nice and clean but I didn't alter any of the porting.

I had her rebuilt only a couple of weeks ago and to be honest Ive not had a really good chance to ride her much yet. I think the shop has put the valves in wrong as they seem to be opening late for some reason. But it could be the change of reeds.

B

B · Feb 23, 2003

Oh and cheers for checking your resistor/ limiter for me.

B

jaguar · Feb 23, 2003

The resistor measured 6 ohms. I'd guess it's about a 100 watt resistor.
I read that someone else with a SR stripped out the noise insulation from the pipe and left it without much umph except for top end rpm power. He said the SR's head pipe is fatter than a regular R version pipe which accounts for the difference. How'd your mod turn out?

B · Feb 24, 2003

Im really impressed with my SR mods, but Im looking for a newer bike now as its all getting a bit worn and rattly. Not just the engine as Ive had it rebuilt recently and it kicks as well as it ever did, but I was sat next to a 98/99 KDX the other day and mine just sounded so much noiser. On a flat tarmac drag, the older one kept up very closely to the other bike. But the other bike sounded so much sweeter.

B

jaguar · Feb 24, 2003

well, a drag race is just a test of top end power. what about mid range power? How is your bike? Does it feel strong way before the power valves open up?
Looking in my electronic catalogs I have came up with this possible substitute:
Original resistor: 6 ohms, 84mm x 16mm x 16mm, ? 50-100 watts
Part #TMC50-6.0-ND $4.74 6 ohms 51mm x 16mm x 16mm 50watts
source: DigiKey Corporation, tel 218-681-6674 http://www.digikey.com

motopsycho87 · Jun 2, 2011

8 year old thread, does anyone know if the porting is different then?!

jaguar · Jun 2, 2011

I was going to order a cylinder sleeve for my SR but the sleeve for the regular KDX was slightly different. I don't remember details though. I would guess that the SR is ported a bit milder.

motopsycho87 · Jun 3, 2011

I suppose I will just have to wait til I rip it to bits, interesting thing though, my exhaust is held on by springs, I think its Thai make called "Pro-Skill". Perhaps the company made a conversion kit or something once upon a time, or perhaps my bike had a different barrel fitted... more likely a conversion!

Can only wait and see, I've gotted a spare head off of ebay, given it a skim and re-profiled / polished the head, would be nice for a barrel to turn up some time!

Would be awesome if anyone with the R version could measure the heights and widths of their ports for reference when I strip her down.

KDX200SR top end differences

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