Vforce 3 lifespan?

[Jr.]

Is this a common problem with Yamaha's? I don't recall seeing that happen
to a Kawasaki before. Is that something you have seen on MX bikes, I have
seen an engine builder regularly cut the cylinders to move the reeds forward.

Bill M.

I wouldnt necessarily call it a problem? It is common on both Kawasaki and Yamaha watercraft that have been modified, or altered using aftermarket intakes. I cant speak for MX bikes, as I dont have background in them.
I come from Modified outboard racing prior to getting into skiis. The practice of altering cases for bigger reed blocks, large carbs ect , and moving them for better flow is a regular operation for many motor shops, mine included. The reeds are a wear item. In pro level race skiis, where stage V porting is the norm, changeing out reeds after every race weekend. Even pro level freestyle skiis get torn down for full rebuilds on regular basis. Far more ofter than a weekend warrior would even dream of doing. General rec riders are looking to get full seasons plus before rebuilds.
So a degree of give and take needs to be applied. Personally, I would never, or better stated, rarely ever, recomend carbon reeds to a weekend, freerider, or freestylist. They just dont have the life span for that type rider
IMHO a good set of glass reeds gives much more consistant, long lasting performance, at a more reasonable price point. Then again, there is that 1% who have to have the best of the best....... at any cost!

Ski ya, Paul

 

[Flash-FX]

I ran a couple sets of V-3 reeds in my SS865 that had epoxied cases and intake runner tracts (Boyesen manifold). After a couple of hours of custom grinding the cages to make them fit, and making a couple of gaskets, I fired it up. The first impression was WOW! These reeds really increase the response. Super crisp!
Well, they lasted about a tank of gas until the tips and corners began to break and chip. The tell tale sign of bad reeds is a false rich condition. After talking with the factory guys, (they thought I was crazy) I came to the conclusion that even though the overall reed area is much greater than stock (less reed opening for the same CFM of airflow), the V-3 pedals are so thin that they begin to collapse into the openings. Then chip and break. (they can't handle the high crankcase pressures). I run the Boyesen cages and reeds now without any issues.

In your case, (like Jr. mentioned above) the tip of the reeds are probably too close to the spinning crankshaft. Bottom line.... get some manifold spacers, or a PHP manifold that accepts V-3 reeds.

 

[Freakrider]

When I was deciding to buy Boyesen rad valves or VF3's I was surprised when Chucky told me that VF3's were the best performing reeds out in his opinion. Surprised because XS setup so many engines with rad valves in the past.

 

[Big Kahuna]

When I was deciding to buy Boyesen rad valves or VF3's I was surprised when Chucky told me that VF3's were the best performing reeds out in his opinion. Surprised because XS setup so many engines with rad valves in the past.

Because they were using Full Specs.

 

[Freakrider]

Because they were using Full Specs.

Chucky knew I was using FS 49's and still recommended VF3'S.

 

[Big Kahuna]

Meaning if they supplied the full intake setup it would be they boyesens.

 

[Jr.]

V3 is a very good performing reed block. I can see why Chuckie recomended them. For my setups, I dont recomend them for general use, as to the short life span. But, for riders looking for the most and willing to change out the pedals every week or two? I pic the V3 over the rad valve fairly often. Goes back to the builder and what recipe of parts works for their setup. No right or wrong, just what works.

 

[Roseand]

V3 is a very good performing reed block. I can see why Chuckie recomended them. For my setups, I dont recomend them for general use, as to the short life span. But, for riders looking for the most and willing to change out the pedals every week or two? I pic the V3 over the rad valve fairly often. Goes back to the builder and what recipe of parts works for their setup. No right or wrong, just what works.

For the rad valve you need the boyesen manifold correct?

 

[Storbeck]

V3 is a very good performing reed block. I can see why Chuckie recomended them. For my setups, I dont recomend them for general use, as to the short life span. But, for riders looking for the most and willing to change out the pedals every week or two? I pic the V3 over the rad valve fairly often. Goes back to the builder and what recipe of parts works for their setup. No right or wrong, just what works.

Out of curiosity, what do you recommend for the rider that doesn't want to replace reeds so often?

 

[Jr.]

They used to make them for the oem 62t manifolds? Im pretty sure you can still get them from Boysene direct.
Part #131
There was also a set on here used several months back? Here is the link, but Ad states sold?
http://www.x-h2o.com/index.php?thre...-carbs-single-carbs-and-manifolds-etc.174111/
Also, member #Headshock had a set for sale? Not sure if sold? Maybe message him?

 

[Jr.]

Out of curiosity, what do you recommend for the rider that doesn't want to replace reeds so often?

Thats easy, Boysene Pro Reeds. Direct bolt on 62t oem cages Very strong and withstand frequent water injestions,
Very good consistant performance, with minimal fade over time.

Another option that I have been doing for years is fitting Kawasaki 750 cages to work on 62t manifolds
Run same Boysene pro reeds (K750 fitment) these have slightly larger cage area, allowing more flow than Yam, and a better angle of attack into case. Can be modified easily with a dremmel tool.
I think I have a set in a box someplace? Let me see if I can find them and post pics?

 

[Storbeck]

Thats easy, Boysene Pro Reeds. Direct bolt on 62t oem cages Very strong and withstand frequent water injestions,
Very good consistant performance, with minimal fade over time.

Another option that I have been doing for years is fitting Kawasaki 750 cages to work on 62t manifolds
Run same Boysene pro reeds (K750 fitment) these have slightly larger cage area, allowing more flow than Yam, and a better angle of attack into case. Can be modified easily with a dremmel tool.
I think I have a set in a box someplace? Let me see if I can find them and post pics?

I'd be very interested in seeing the kawasaki reeds modified to fit the Yamaha.

 

[Jr.]

Ok, Found them, In the pic showing the 3 reed blocks. OEM 62t on left Modified K750 in the center
Un-modified K750 on the right. If you study the Yam vs Kaw you can see the angle differance aid to open area.
You can also physically see size advantage to the K750 over yam

 

[Storbeck]

Interesting stuff thank you.

Since we're off topic anyway....recently I was comparing reeds on some other motors I had on hand. YZ250, Yz125, polaris 800 snowmobile, 66e yamaha, and looking at pictures of basically any high performance two stroke I could find...and it sure looks like if you compare reed cage size to horsepower, or reed cage size to the size of the carb being used, a big motor based off of a 62t case, with 46mm+carbs... the reeds are proportionally pretty small.

 

[Req]

Ok, Found them, In the pic showing the 3 reed blocks. OEM 62t on left Modified K750 in the center
Un-modified K750 on the right. If you study the Yam vs Kaw you can see the angle differance aid to open area.
You can also physically see size advantage to the K750 over yam

What are your thoughts on the GP1200 (non pv) reeds and cages with 62t petal stops? They are larger and require no grinding, however they block the boost port with the 1200 petal stops.

 

[CARBONX2]

Interesting stuff thank you.

Since we're off topic anyway....recently I was comparing reeds on some other motors I had on hand. YZ250, Yz125, polaris 800 snowmobile, 66e yamaha, and looking at pictures of basically any high performance two stroke I could find...and it sure looks like if you compare reed cage size to horsepower, or reed cage size to the size of the carb being used, a big motor based off of a 62t case, with 46mm+carbs... the reeds are proportionally pretty small.

The size of 66E reedvalves for what is actually a 785cc engines says a lot.

 

[Jr.]

Reed blocks and flow into the crankcase is an oftern overlooked part of the flow path into a motor.
For the most part, the increased flow is almost always better. But there is a basic rule to follow.
What goes in, must go out, what goes out, must first go in! It all needs to match flow and compliment airspeed thru the motor. Its common knowlage that the OEM’s design certain parts to guarantee the motor lives thru Warranty and beyond. Creating a log jamb if you would with flow, is certainly one way to accomplish that goal.
The reed block can most certainly be designed larger from the factory. However they dont.
Thats what opens the door to the performance market.

For the question on the reed stops? Ever Consider removing them entirely? Boysene Pro reeds provide a torque strip for just that purpose. I would never do that with a carbon reed pedal tho. They would snap right off.

 

[Jyzmbe]

I have a angled reed spacer if you want it


Sent from my iPhone using Tapatalk

 

[Octane_114]

That it typical of what we call Flutter. Its caused by turbulance coming off the crank. A common solution is to install reed spacers. Some manifolds like the Boysene and others, have the reeds spaced back from within the manifold, so a spacer is not needed. What manifold are they bolted to?? You also stated that your cases were epoxy filled?Im guessing you mean the fingers are filled?? What this does, is reduce volume, but increase air speed thru the reeds.
Typically done in high rpm motors. Unfill maintains volume, aids in low end performance. Reguardless what option you prefer, the reed pedals take the brunt of the added flutter. Carbon reeds wear faster in high flutter, than say Boysene pro reeds which are all glass. Bottom line, there is no right or wrong to this. It Is how you or your builder chooses to have the power delvered. Its how the recipe of parts compliment each other!

Ski Ya, Paul

Wow! Great answer. Lot of folks don't this at all. They always think/believe one is better than the other.

 

[Roseand]

I contacted vforce about my reeds, they told me to send them in for inspection. Just got an email back that said they took care of them and are shipping them back. They stood behind their product.
I wasn't expecting that!