250-500cc WR 300 race head short review

^^^ Yep. Your 250 already has higher compression and might not benefit as much as a 300 would though - not sure on that one? I race a same era WR and I've left mine stock. I can pass some 450's in the open if I am brave, so I haven't messed with it...

What's the # to RD Designs? Any idea on the cost for this mod?

http://www.rb-designs.com/

Current setup is:
Keihin Airstryker PWK 38mm
Jetted with a 45 pilot jet
170 main jet
Blue needle in the 3rd clip from top down.
________________________________
My current running conditons are:
Mix 40:1
Oil: Castrol Power RS TTS Full Synthetic.
Elevation 0-300mtrs
Temp - 15- 35 degrees C
Humidity 40 - 60%

Type of riding desert, soft sand (fast trails)


I will take the helmet camera out on my next ride so you can see how she goes

Ok, thanks for the info! There´s no desertriding here! We started our iceracing season today! Great fun with long powerslides on the ice. I use 14/42 gearing on the ice, EEL needle in 3rd, 45 pilot and 182 main at about zero degrees. Humidity around 85-90%.

Johnny

I dont think we could find more contrast than that Stupid question...
Whats an EEL needle?
Have you tried a paddle tire in the snow? wonder if it would work

EEL needle is one of Keihin´s own needles. I´ve been trying out different needles to learn about jetting and to see how the needles affect the caracter of the engine. This makes a very big difference so now i have the possibility to jet my bike just how i want it depending on where i ride and how i want it to be. I have a bunch of needles to mess with! No, i haven´t tried a paddle tire, because as soon as you get down to the ice you have no grip at all! Our Motocross tires with 12-15mm long screws works wonders on the ice! Wheelies out of the corners and stoppies into the corners!
BTW: Blue needle in 3rd feels rich to me. have you tried it in lower position? I also think a 40 pilot would work fine. I use a 45 now and we have about zero and below at 1000ft! 1,5 turns out.
Johnny

I think its around $70.

Best way to reach Ron is via email: rblack66@comcast.net
He's a one man shop and he will not drop what he's doing to answer the phone, so email or calling will yield similar response times and he prefers emails. BTW, he does superb work and is a super nice guy to boot.

I'm dropping off my 300 head today or tomorrow for the treatment. And since I cant even get a squish measurement with .125" solder I'm hoping for a nice gain, especially since I am going to ask for a substantial compression bump. I'm hoping this will wake up the soft bottom end.

My race cylinder head is now on it´s way to Sweden! It will be intresting to try it out when it arrives! All of you guys who´s using it: Does anyone having problems with pinging? What fuel are you running? We have 99 octane in the pumps at best here in Sweden.

On mine, no pinging on 94 oct. I have 165psi.
From all testing i have made with 2 strokes, 200 psi is the limit for pump gas. Over that i use VP C16.

! Thanks, sounds good! I check my ignition too. Is it easy to adjust? Anticlockwise?

No beta testing required. He's done hundreds, if not thousands of them.
He's not reinventing the wheel, just fixing the mass-production tolerances...


After this I'm going to look into the digital ignition. Anyone priced it out yet?

Do you talk about the Ducati ignition ???
If yes, its too expensive... for me.
$346 stator
$262 box
$174 wiring...

I think for $780 you can have better performance gain... My stock timing is advance 4 degres and the response is perfect. I dont think the stock ignition is a "bottle neck" in performance on the WR300...

Wow!
Forget that. I'll go buy a beater 125 for that kind of change!

Thanks!

How much do they mill off the Head? Would the 250 benefit from such a mod? I have two friends with the 300 and I have the 250.

Mike

If you were in all powder snow maybe but if the snow gets hard, the tire will be ruined quickly ...

For dyno results with head and carb mods
this thread is good reading
http://www.cafehusky.com/forums/showthread.php?t=10628&highlight=DYNO TUNING

15mm crikey that would rip ya leg open like a polar bear if it got a hold of ya
Being a newbie to 2 strokes I dont know how to adjust the needle I was happy with myself after changing the jet!
Hey if you get a chance post some pics... Im sure this is something not many of us get to see