CR125 reed valve choice

Hi, it's my first post here, first of all i' m italian so excuse me for my really bad english.

I have got a 2004 Cr125 and i want a bike with more lower at lower rpm, cause now i use it in enduro/woods riding....

There are differences between a V-Force 2 reed valve and the V-Force 3?

A boyesen, or a rad valve have more power at higher RPMs?


Noone? :bonk:

Welcome to TT, you're in the right place.

For your needs, the VForce setup is what I would recommend, and it's usually less expensive too. This will give you nice, crisp throttle response. It smoothened that hit off the low-mid, which makes the bike more controllable, and it also added a quite noticeable boost in the power from low-end up through the mid-range.

There are usually no jetting modifications required, except maybe an air screw adjustment. This means that it does not give as much overall horsepower as the Boyesen system, which does require them. From what I understand, the Boyesen is more of a mx application and focuses on the mid-upper RPM range for racing, which doesn't help you much on the trails.

thank you....

ok, i will get a v-force......but which is better?

the vf2 or the vf3?

somebody told me that with vf3 sometimes you can break the carbon fiber reeds.....and that never happens with vf2...

and about the erogation of power.....are they different?


i have heard all kinds of things about reed valves... like making your bike feel 20-30cc's bigger. or faster. or power on different spots.

in my trial and error with them i cant find much of a difference between stock, boyesn, and vf's. boyesn seemed to give me a bit more low end while vf's gave me a little more high end. even bought the vforce reed cage to see if it would help-not really. but again it was a slight difference and not really worth buying a 2nd set of reeds.

thank you....

ok, i will get a v-force......but which is better?

the vf2 or the vf3?

somebody told me that with vf3 sometimes you can break the carbon fiber reeds.....and that never happens with vf2...

and about the erogation of power.....are they different?


I had the Vforce3 only. I rode the bike hard for over a year with it and had absolutely no problems with the reeds, although it was getting close to the time where I would have replaced them for maintenance/reassurance anyway.

From hobo99's comments: I wouldn't claim that it feels "20cc larger", in part because I had my bike bored to 134 and know the difference, but I can understand where that's coming from with the improvement on this PARTICULAR bike in response and quicker surge through the midrange. There's an RM in that avatar and I can't speak for the improvement they get with the valve.

Like stated above, VF and Boyeson are both good. I have a Boyeson Rad valve on my 98 and it did seem to add a little bottom end and mid range. But, for the money, I proabbly wouldn't do it again. A few hundred bucks put into other places would make the bike faster IMO.

Yes i currently own an rm, but work on all kinds of machines. Overall i tell people that reeds aren't magic and likely wont give you more power. yes they can change characteristics and delivery.

For me i would put money into a pipe or bb kit over fancy reeds. (Not saying they are not a good product.)

The most difference I felt out of the vf3's I installed on my 03 was the trottle responce. It hits harder faster and feels $150 dollars more crisp off the bottom. I also feel that with the combination of the electric power valve, reeds and pipe honda made one of the smoothest hitting and most predictable powerband delivery systems ever.

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