Rad Valve and Moose spacer?

[JRRacing]

Seems everyone suggests the V-force. Any reason not to use a Rad valve and moose spacer?

[sandblaster]

The rad will give you better bottom end where the VF2's will give you better mid to top.
So it all depends on the kind of riding you do, your engine's state of tune, and your style.

[JRRacing]

90% Vet motocross, 10% woods. I've always considered myself more on the aggressive side of riding style but not so much since I picked this bike up. lol

SB also whats the consensus for Motocross gearing? THANK YOU!

[sandblaster]

We are building Sean Collier a new bike.
We are using a Rad and a 10mm spacer.
We are not building a fire breathing dragster... Just the opposite.
We are trying to build more torque... and we will 
His current bike "The Beast" which was built by Frenchy is very mildly ported and it wears Sean out.
So if I was going to MX it I would use the Rad and the 10mm spacer.
Woods Gnarly
Gearing?
It would depend on the track...
Sean use to use a 14/51 but was wearing out the chain guide bad.
Currently Sean is running a 13/45 which is close to 14/48.. stock being 14/47
I know some others that run 14/47 on mx tracks..

[JRRacing]

 Great information , thank you. Bike came with a Pro Circuit platinum. Ditch it for the FMF you mentioned?

[sandblaster]

For a MX track, yes, the Woods Gnarly would be better..

[Dutch-K5 Fan]

I ise the old Rad valve and makes it a bit more mellow.
That may sounds a option for softies. Think it would do you good.
It revs a bit "slower" to.



Dutchie

[Desto]

We are building Sean Collier a new bike.
We are using a Rad and a 10mm spacer.
We are not building a fire breathing dragster... Just the opposite.
We are trying to build more torque... and we will 
His current bike "The Beast" which was built by Frenchy is very mildly ported and it wears Sean out.
So if I was going to MX it I would use the Rad and the 10mm spacer.
Woods Gnarly
Gearing?
It would depend on the track...
Sean use to use a 14/51 but was wearing out the chain guide bad.
Currently Sean is running a 13/45 which is close to 14/48.. stock being 14/47
I know some others that run 14/47 on mx tracks..

Sean is a cool dude.....got to start on the same gate with him at LACR and joked around saying I had him off the start and into the first turn, then I seen a green blur go by. 😎He did dig my bike👍

[RoostiusMaximus]

I don't know that the rad valve is the ideal setup for low rpm, or high rpm but I use it because we modify it for the Pulse Induction systems.

The VF2 will always be my favorite reed for non-pulse fed engines.

The VF2's pedal tension is low but the angle is steep, so it opens further under less vacuum and flows more cfm at wide open position.
Talking in terms of rpm the VF2 will also go full closed to go max open faster than the rad valve, so really it is capable of moving more air per crank stroke because it is full open for a longer duration.

Consider the following to be in regards to them both having the pedal tips spaced the same distance from the piston.
Power wise if you were to check the engine at a peak number i'm certain they are close to the same.
Throttle position to ground speed I'd say the VF2 hands down.
There is the possibility that a rad valve could act smoother at idle to 1/4 throttle opening if the airstriker carburetor was used.

In personal experience the pedals of the rad valve don't last 1/2 as long as the VF2.

I'll always be the guy to build the engine strong on torque, if the bike comes out of the corner too abrupt I'd gear it taller, pull the gears longer and it will be faster, smoother and be under control longer since the chassis is going to be in the same position longer and not loading - unloading with gear changes.

[RoostDaddy]

The rad will give you better bottom end where the VF2's will give you better mid to top.
So it all depends on the kind of riding you do, your engine's state of tune, and your style.

And also your carburetor size!

[sandblaster]

All good points... Which is why we are going to be doing a series of dyno tests with different products over the next several years and Oscar is going to be doing some video's on his blue smoke series which will document what really works and what does not.

One of the things I want to do is the Rad, vs VF2 at the high and low tension settings, vs VF3,  reed spacer vs no reed spacer, ect. A whole series on carbs. Pipes, mufflers. That's gonna be the easy stuff to do.. We will be going much deeper then that 

Roostius has really opened my eyes as to a lot of Koolaid we have been drinking so be prepared to have your Paradigm burst