Adjustable power valve cover

[Berkyboy]

We just started getting some information from Trusty and that 300 euro mark looks like suggested consumer retail, ouch.

[swazi_matt]

surely for most riders the dual mappping switch (although slight) is enough to get a bit more spunk out of the bike when needed, would think the adjustable pv cover would be more for serious racers - my 2c anyway

[iancp5]

Originally Posted by Elvis74

Hello,
I know that you can buy this part here in Germany, it cost est. 300euro and you have to bring the motor to www.gasgas-werl.de!!! This part is used in the WEC and also nt the european enduro chanpionship. With this adjustable power valve cover you can change the character of you bike, from aggrassive Motocross to smooth enduro power.

drive fast fligh high
Elvis74

What mormally damps the opening. They must remove something otherwise it can only slow things down not speed it up?

[GMP]

The left drum valve acts on a spring that is preloaded by the adjustment knob in either the + or - direction (force). So, the total force the governer must overcome to move and open the valves is that of the governer spring plus the PV cover spring, which effectively either adds to the resistance (slower opening) or subtracts and assists opening(faster). Clever, just too much $$ IMO.

[mountain thumper]

if i could somehow get my hands on one, i could make a cnc program for it, with some difference for obvious legal reasons the parts involved would be significantly cheaper than $600 usd, and the program would be compatible with most 3+ axis cnc machines. i already have a pv cover drawn up, but i need to take measurements from the rest of the parts, and actually see how it interacts with the valve.

ive read that ktm offers one for their bikes, a gg peice could probably be engineered from one of those, assuming the pv is similar...
but along what swazi was saying, wouldnt it be a pain in the ass to change while riding, would a handle mounted choke adjuster be enough to move the knob perhaps?

[iancp5]

Originally Posted by mountain thumper

wouldnt it be a pain in the ass to change while riding, would a handle mounted choke adjuster be enough to move the knob perhaps?

It would be a pain to change while riding but still useful to change when stationary. When you get to an event you could make a decision on where you want it set according to conditions. At the moment it's not adjustable at all. On European timecard enduros there are plenty of opportunities to adjust during an event - at checks or before a special test. I think a handlebar adjuster is not worth the added complication - something else to make room for or break. But that's just opinion.

[swazi_matt]

a bit of a hijack, but i was also looking at the larger volume PV cover and a bit surprised at the cost. Firstly does it make a huge difference, and are the actual dimensions critical, was thinking of getting a machinist here to make a spacer piece about 5mm thick that would go between the engine and the original pv cover, should work out a lot cheaper ... any thoughts welcome

[iancp5]

Originally Posted by swazi_matt

a bit of a hijack, but i was also looking at the larger volume PV cover and a bit surprised at the cost. Firstly does it make a huge difference, and are the actual dimensions critical, was thinking of getting a machinist here to make a spacer piece about 5mm thick that would go between the engine and the original pv cover, should work out a lot cheaper ... any thoughts welcome

When I had a 300 I found it better without one but I use one on my 200. The 300 has plenty of torque and response anyway. The PV cover just made it difficult when slippery. I found the best setup to be a Doma pipe, no PV cover and a CCK needle. I was looking for smooth linear response but others prefer it to hit hard. Personally I think that is slower on a 300, for me certainly.

[bchatt]

Originally Posted by swazi_matt

a bit of a hijack, but i was also looking at the larger volume PV cover and a bit surprised at the cost. Firstly does it make a huge difference, and are the actual dimensions critical, was thinking of getting a machinist here to make a spacer piece about 5mm thick that would go between the engine and the original pv cover, should work out a lot cheaper ... any thoughts welcome

I made a spacer 10mm thick for my 250. It seemed to make no difference, in fact I thought the engine was stalling more easily, so I took it off again. That said, it looks like the proper cover is much deeper - maybe 25mm. This could be the difference.

[swazi_matt]

thanks guys, i think half my problem is i am still in kx mode where i was costantly trying to get more torque for the bike. when i think about it the gg300 has plenty and if i need more i can just gear down on sprocketing, but so far i am v v happy