Boyesen Power Valve or Vforce Delta 2 reed system?

jbird_710 · Post by **jbird_710** » May 9th, 2009, 4:23 pm

If you had the choice between a Boyesen Power Valve or Vforce Delta 2 reed valve system for a CR500 that will be used only on MX tracks, which would you choose? The carb, cylinder, and piston are stock. It will have a Pro Circuit works pipe with a PC304 silencer.

nmdesertrider · Post by **nmdesertrider** » May 9th, 2009, 4:48 pm

Not sure if you are building an AF but the boysen makes it a lot easier to fit everything together.

CR500PHIL · Post by **CR500PHIL** » May 9th, 2009, 6:16 pm

I have not used Boyesen but I hear it is a pain to get the carb tuned properly with them installed. I love vForce reeds - I had them in my YZ250 and I now have them in my CR500 - they are awesome, not only for the throttle response but they also clean up the jetting quite nicely.

jbird_710 · Post by **jbird_710** » May 9th, 2009, 7:15 pm

Yes, it's going on an '02 CRF450R conversion. I've got all of the parts together to do the custom fork boot connection per the instructions from another thread. I will be re-jetting in the future when I get the old cylinder ported and re-install it. I'm installing a stock cylinder and piston as a temporary setup so I can ride while the other work is being done.

100hp honda · Post by **100hp honda** » May 9th, 2009, 9:25 pm

jetting with rad valve is real similiar to stock reeds. that doesnt seem very difficult to me. might need 1 size bigger or smaller but its real close

CR500PHIL · Post by **CR500PHIL** » May 10th, 2009, 7:29 am

100hp honda wrote:jetting with rad valve is real similiar to stock reeds. that doesnt seem very difficult to me. might need 1 size bigger or smaller but its real close

Well like I said I have not used them but I read a post on another site where the author mentioned it being difficult to jet for them but obviously that guy did not know what he was talking about.

100hp honda · Post by **100hp honda** » May 10th, 2009, 9:13 am

i like the rad valve personally and have used them on 2 different bikes. theres definatly no secret to figuring them out

nmdesertrider · Post by **nmdesertrider** » May 10th, 2009, 3:54 pm

My friend switched his over from stock to boyson and he didn't have to change jetting and the bike runs great.

LAYNFRM · Post by **LAYNFRM** » May 10th, 2009, 6:11 pm

i have the V force delta 2 cage, and i had to trim the front corners a little so it would fit in the case. it's like it was a little to wide on the piston side and needed to be tapered or something.

seanmx57 · Post by **seanmx57** » May 11th, 2009, 2:25 pm

I had a VF2 and switched to a RAD becuase I was told by AJ that they are easier to jet. Neither would jet worth a damn with a bad stator/crank seal

Since that's been fixed I have been running the RAD. It jets fine.

FattyFive · Post by **FattyFive** » May 12th, 2009, 8:46 am

I run a rad valve myself, but dont do any mx

Had a vf2 on a yz250, Went back to stock. My .02.

kkvslayer · Post by **kkvslayer** » May 12th, 2009, 10:29 am

LAYNFRM wrote:i have the V force delta 2 cage, and i had to trim the front corners a little so it would fit in the case. it's like it was a little to wide on the piston side and needed to be tapered or something.

I had to hit mine with a dremel too but not on the front egdes,had to make the cage a bit narrower on the L & R side near the sealing surface so it would seat properly,I know theres a few more guys who have had to do it like this,no big deal really,takes a few minutes,been running it for 2 seasons,prolly 7 or 8 months total and it still looks and performs as when I put it on,no complaints here

britincali · Post by **britincali** » May 12th, 2009, 12:34 pm

kkvslayer wrote: I had to hit mine with a dremel too but not on the front egdes,had to make the cage a bit narrower on the L & R side near the sealing surface so it would seat properly,I know theres a few more guys who have had to do it like this,no big deal really,takes a few minutes,been running it for 2 seasons,prolly 7 or 8 months total and it still looks and performs as when I put it on,no complaints here

Same here.

dannygraves · Post by **dannygraves** » May 12th, 2009, 12:56 pm

only '85-'88 jugs need the sides to be trimmed.
I like the vforce, they will last longer than a rad valve and flow the most by design. the downside is the shape on the inside relating to flow through the air boot. it opens up to a perfect rectangle from the oval shape of the boot and creates turbulance. the quick fix is the trim the boot to match. makes a noticeable difference.
my gen-1 is running the vforce where I modified the reed cage inside and out and modified the boot so they are both very large and oval shaped. made a big difference w/ the 41mm carb on there.

I don't see any reason to install a set on a stock bike. OEM reeds are killer in a stock or mildly modified setup. I prefere the vforce on a built setup because the pedals are stronger and the whole assembly flows more which comes in handy with a lot of porting and a larger carb. On a stock bike, I hear they are supposed to improve throttle response, but thats about it.

jbird_710 · Post by **jbird_710** » May 13th, 2009, 11:12 pm

Thanks for the input. I think I'll wait until I get the old cylinders ported and other pistons to install the reeds. I'll stick with stock until then.

CR500PHIL · Post by **CR500PHIL** » May 19th, 2009, 7:36 am

FattyFive wrote:I run a rad valve myself, but dont do any mx Had a vf2 on a yz250, Went back to stock. My .02.

My 2003 YZ250 fouled plugs because of rich low end jetting right from the shop when new. I put in the vForce 3 reeds and never fouled a plug after (perfect brownish-gray plugs) and I noticed improved throttle response as well. That is about all I noticed with the vForce but that alone made them worth having. I bought the same for my CR500.

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Boyesen Power Valve or Vforce Delta 2 reed system?

Boyesen Power Valve or Vforce Delta 2 reed system?

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