KX500 exhaust valves NICE!

[Sandblaster]

A picture says more than I can:

k5 exhaust valves.jpg (189.58 KiB) Viewed 12829 times

k5 exhaust valves 2.jpg (193.79 KiB) Viewed 12827 times

[81cr450]

Those do look sweet. There's a mildly abrasive wheel on the grinder @ work, its actually for tool sharpening but it will shine them up nice like that. I like to hit the area in where the exhaust would flow through too so the carbon has a harder time sticking there as well.

I would still like to know a great way for making the ramp in the sides, for the center flap, a bit more agressive

[Sandblaster]

I would still like to know a great way for making the ramp in the sides, for the center flap, a bit more agressive

Have you talked to Motorrad about it?

I didn't do the valves.
They were done by alward25
Although there is a chance I will end up with them....

[81cr450]

Have you talked to Motorrad about it?

Yup his idea but he we'rent sharing . Be nice to really make some LUGG'ing power

[Sandblaster]

Yeah, some guys can be a bit tight with info especially those whose living is dependent on the info they came up with.
But motorrad has been fairly forthcoming with hard numbers when asked unless one of the big boys asked him to be quiet.
I can see that where you ride that torque would be king.
I'm sure you have geared down and added a fly wheel weight and maybe a reed spacer.
How about Fuel injection

[81cr450]

Let me show you my "reed spacer"



The shorter one is the VF2's.

Really though its hard to give up the hit where I ride we have hills a 250 wont pull cause they just dont have enough power to pull from a dead stop & get the momentum moving. The 550 was a bit much but honestly I'm going to do it again. Gearing is at 15 47 but if I can get the first gear to go together I should be able to step into the 16 45 range easy enough. I guess the gearing I run is part of why I dont like flywheel weights, Todd P. says the 125/250 ignition hits even harder which has me tempted. My cr is geared 14 43. Its just the area , you want the high speed for the desert connecting runs but when you get to the hill you still need the snap out of the bottoms of these deep V'ed washes that shoot up football fields standing on end.

EFI sounds nice but I'd really have to "see" it work first. I have an idea or 2 about it but it'll be a ways off for me yet. I'd really like to see 3 injectors , one running your lightly dilluted premix into the airstream at the reed tip, you could use AF frame rails to carry this mixture. Then you'd have 2 right about the level of the top of your exhaust port, on each side pointing to the rear so your only putting in fuel at the last moment. It'd need to be before the exhaust closed though cause I'd guess the pressure would spit the injectors out. My "guess is it would be near direct inject fuel efficiency , but.. its all just internet mumbling for now

[Sandblaster]

I like your spacer. Nice.

On the EFI I see that you have thought about it some.
Out of all the possibilities I have read your idea seems to have the most promise without a complete redesign of the cylinder
I really like using the frame for the premix.
It's just a nice touch.
Ultimately I think direct port would be best but I don't see a good way of doing it with a stock cylinder.

[81cr450]

On the stock cylinder I think you could run it direct into the cylinder, not even into the siderunner. Its all aluminum just drill a hole then put a tube / injector bung in the hole. You'd want to 45* bevel this bung on the end that goes into the cylinder bore so it could be attached / sealed in the bore by a competent welder then just weld up the outside like you would any injector bung. When they bore it before re-nikasiling the weld slag gets cut out & Viola. Think how big the bore is & how small a tig torch is, should be fairly easy

I stole the premix idea, on banned cr500 riders they use the frames to haul an extra half gallon of fuel

[Sandblaster]

Yes I agree that it should work no problem.
I'm just wondering about the efficiency, timing, ect.
I have not looked at the snowmobiles but I wonder if they are injecting through the cylinder or the head?
It seems that snowmobiles and some of the modern boat engines have really advanced fuel injection, turbo charging ect for 2T's so I'm certain there's some lessons to be learned.
If I was going to get serious about it I would be checking them out real careful before I started.
I love learning from others experiences

[81cr450]

I love learning from others experiences

Absolutely & learning on their checkbook too

Thats part of "see" it work first. Easy to bench race