Powervalve issue?

[adriano.ro]

I know how to do it but I don't know how much preload to make on it. I saw somewhere something about filer gage( is the corect name,for tool that mesure thickness?).

I have an annoying flat spot between 25%-55% of throttle. I suspect the power valve preload. Now is ok,no slop or to much freeplay .

Gear ratio is 13-50
Carb: 40p NECW#3 -some riders find this needle too soft on bottom, it can be part of my problem.
Main jet 170.

 

[Jim Cook]

I know how to do it but I don't know how much preload to make on it. I saw somewhere something about filer gage( is the corect name,for tool that mesure thickness?).

I have an annoying flat spot between 25%-55% of throttle. I suspect the power valve preload. Now is ok,no slop or to much freeplay .

Gear ratio is 13-50
Carb: 40p NECW#3 -some riders find this needle too soft on bottom, it can be part of my problem.
Main jet 170.

I have been running a 42 pilot jet on my AS2 (2011).
If your pv is close to right, it shouldn't cause a flat spot at 25%-55% throttle. That sounds more like a jetting issue.
Lots of riders really like the NEDW, so I don't think that's the problem. Have you tried the needle clip in the 2nd groove from the top?
That should lean the jetting a bit in the 25%-44% throttle range, and may make a huge difference.

The thickness measurement tool is a "feeler gauge".

Good luck!
Jim

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[adriano.ro]

So the next thing to check is power valve preload and shims! Someone is got photo with the pv assembly where I can see the shims?

Next stept is jetting.

Update soon.

 

[barossi73]

NED_ is half clip richer than NEC_

NEDW #2 = 1/2 clip leaner
NECW #3 (you)
NEDW #3 = 1/2 clip richer

Mines a 200(as2 carb 2screw cap) so diff diameter Nech/Nedh but i found i needed the half clip options to get it dialed that little bit sweeter.

 

[Jim Cook]

So the next thing to check is power valve preload and shims! Someone is got photo with the pv assembly where I can see the shims?

Next stept is jetting.

Update soon.

Private message me here and give me your email address, and I will send you a copy of the 2-stroke engine workshop service manual. It is in the pdf format, and I can attach the file to an email.

That will give you photos and procedures for the engine work.

Do you have the parts diagrams? The parts book is available for download; at least those for the newer models are.
https://gasgas.com/us/manuals The operator's manuals are listed as "manuals" and the parts books are listed as "exploded"
.I have most of the older parts books, the ones not included on the web site's list, on my computer at work.

Good Riding!
Jim

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[adriano.ro]

Private message me here and give me your email address, and I will send you a copy of the 2-stroke engine workshop service manual. It is in the pdf format, and I can attach the file to an email.

That will give you photos and procedures for the engine work.

Do you have the parts diagrams? The parts book is available for download; at least those for the newer models are.
https://gasgas.com/us/manuals The operator's manuals are listed as "manuals" and the parts books are listed as "exploded"
.I have most of the older parts books, the ones not included on the web site's list, on my computer at work.

Good Riding!
Jim

.

Tnx a lot Jim, I already have parts diagram in PDF format, repair manual is ok but too vague for what I want.

 

[adriano.ro]

Update:if I adjust pv preload a little bit higher, will not rich full operation,but the bike will rev nice and linear until the power valve start to open.

If I set too soft the preload,will open 90% but with sag on power....

 

[motopsycho87]

I had mine apart yesterday after not touching it for a few years. I'd already had the preload shims out, this time I ground 0.5mm off of the spring also, incredible improvement.

 

[adriano.ro]

What was your symptoms?
My pv spring is red,if the colour means something.

 

[adriano.ro]

Someone cut a little bit from actuator stop bolt ,with very good power gain.

 

[motopsycho87]

I'm guessing they cut it to allow it to open a little further?

I took mine out and ground it to suit the port a couple years ago.

My symptoms were a flat spot down the bottom, like the bike was incredibly lean, but then recovered as the power valve opened. I only really noticed it as I picked up an old exc200, and the bottom end blew me away, so I knew something was wrong. The KTM was set to open mega early, so I knew I needed to get the gasgas to open earlier, and damn did it make a difference.

Bare in mind I'm running 1.5mm base gasket to align the ports, so anything to recover the bottom end is a good thing!

 

[adriano.ro]

I really don't know what to do next.
All is place,nice,clean but no matter what I do,power valve won't open fully.

This is the end of travel...

If I lose a bit the preload on pv will go just a little bit higher on revs but will go too abrupt in power valve.

Soooooo, what I'm thinking to do next, I will loose all spring preload ,if I do that ,the actuator will be loose too much, but,I will bend the actiator arm,to compensates the freeplay.

Fingers crossed

 

[adriano.ro]

Update: nothing change...
repack final
Clean pv
Clean air filter.

....

#G needle maby?
I feel that the pv need to open earlier.

Is frustrating to not have some basic measurements,like ktm, 'X' dimension for example.

 

[cangy]

My contribution to this awesome Powervalve thread.

I've just sorted my Powervalve issue out, and it's an new issue to the thread I think.

If you've ever had the governor apart, you will have spotted a little aluminium rings that slides up and down the main shaft. Mine had "picked up" and was intermittently sticking it got to the stage where it was hardly moving at all.

I put it down to bad maintenance, not changing the gearbox oil regular. Anyhow, I don't know if they are available for an 03 EC 300, but I polished the marks out and it works a treat now

 

[Zman]

I was able to put a 2011 PV governor into my 2000 300GG. There are several on Ebay, but it sounds like you fixed the problem.

 

[steliost]

Today I took the slack out of the PV in the EC250 2008 by loosening the set screw and pushing in the governor juuust a bit, maybe less than 0.5mm, while holding the bracket firmly on the stop bolt and tightening again. the bike rattles no more at idle and deceleration and the bottom end improved much. still the top end power feels a bit flat where it should be screaming. I'll play with the jetting some more but is there a chance I may have lost some travel of the PV, not opening fully at high revs, due to pushing in the gov'nor in an attempt to preload the bracket? otherwise very happy with the result.
Can't wait to ride it...
Happy and healthy new year folks! This place is a treasure.

 

[Zman]

If you pull off the exhaust pipe, open the right side power valve cover and remove the linkage, you can rotate the powervalve by hand and see if the power valve is able to move freely and open completly.

 

[Jim Cook]

Today I took the slack out of the PV in the EC250 2008 by loosening the set screw and pushing in the governor juuust a bit, maybe less than 0.5mm, while holding the bracket firmly on the stop bolt and tightening again. the bike rattles no more at idle and deceleration and the bottom end improved much. still the top end power feels a bit flat where it should be screaming. I'll play with the jetting some more but is there a chance I may have lost some travel of the PV, not opening fully at high revs, due to pushing in the gov'nor in an attempt to preload the bracket? otherwise very happy with the result.
Can't wait to ride it...
Happy and healthy new year folks! This place is a treasure.

Thank you for the kind words.
Helping GasGas riders in this way was what we were going for when we started this forum as "Talking Smack" on my (now closed) shop Smackover Motor Sports's web site. Jeff (the webmaster) has been great in keeping it going here.

If you take off the right powervalve cover and watch it as you rev the engine, you can see if the powervalve is moving through its full rotation.

Good Riding to You!
Jim


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[steliost]

Thank you Jim, I will check it the way you described.
I've always been an advocate of this forum and I probably wouldn't own a gasgas had it not been for this place.

 

[Jim Cook]

Thank you Jim, I will check it the way you described.
I've always been an advocate of this forum and I probably wouldn't own a gasgas had it not been for this place.

Thanks for the kind words.

Let us know how it goes.
Jim