bluespark
New member
I was hoping someone could confirm that myPV is working proper? It does stay closed at idle
https://youtu.be/pRd6anPzvuQ
https://youtu.be/lzYAjvG-mnw
https://youtu.be/pRd6anPzvuQ
https://youtu.be/lzYAjvG-mnw
Powervalve issue?
- Thread starter SpeedyManiac
- Start date
NM_GG_Rider
New member
PV visibly moving from exhaust port
Hi gang,
I've spent the morning reading every post I can find about the Power Valve in hope of bringing power back to my '15 300.
Question before I take the right hand side PV cover off is... If I twist the throttle with the engine off, should I see the PV move in the exhaust port?? When I twist the throttle, nothing is visibly moving, but I think it's because the PV moves from the centrifugal force of the engine.
I'd rather not crack open the side if I can avoid it, but it appears I'm going to have to.
Picture is the view I get as I peer into my baby's heart... (Tried to edit so it's not upside down, but couldn't get it right side up)
Thanks,
Rob
Hi gang,
I've spent the morning reading every post I can find about the Power Valve in hope of bringing power back to my '15 300.
Question before I take the right hand side PV cover off is... If I twist the throttle with the engine off, should I see the PV move in the exhaust port?? When I twist the throttle, nothing is visibly moving, but I think it's because the PV moves from the centrifugal force of the engine.
I'd rather not crack open the side if I can avoid it, but it appears I'm going to have to.
Picture is the view I get as I peer into my baby's heart... (Tried to edit so it's not upside down, but couldn't get it right side up)
Thanks,
Rob
Attachments
swazi_matt
Active member
No the power valve is opened by the engine revs, there is no mechanical link to the throttle so you will not see any movement if the engine is off
Yeah that is correct, it is powered by centrifugal force. If you look at the technical section at the first page before you select forum there are some good diagrams and articles on the power valve. Also, your power valve has an external adjuster that makes a big difference in your power delivery,( so I have been told.) so, you might want to check that first.
Jim Cook
Platinum Level Site Supporter
One more thing that I haven't seen in the replies to your post.
Looking at your piston (in the attached photo) makes me think that you might want to do a top end job. The piston is streaked pretty badly. If your rings are also streaked, then loss of compression may be where your power went. A top end job might be best to ensure that your cylinder stays in good shape.
Are you carefully warming your engine before loading it hard with the throttle?
What oil and jetting are you running? My bike is in it's fourth year, and it has yet to scuff a piston like that.
Looking at your piston (in the attached photo) makes me think that you might want to do a top end job. The piston is streaked pretty badly. If your rings are also streaked, then loss of compression may be where your power went. A top end job might be best to ensure that your cylinder stays in good shape.
Are you carefully warming your engine before loading it hard with the throttle?
What oil and jetting are you running? My bike is in it's fourth year, and it has yet to scuff a piston like that.
Sorry to dig up an old post. I pulled apart my top end this weekend and noticed the shaft on my pv bracket is broken, so cane here looking to see if anyone has just welded it back on.
In any case found this thread (and this post). I'm sure I moved the plate around with the arm attached during disassembly. However, the engine was off. Is this warning only for when the engine is running?
swazi_matt
Active member
No it applies to when the engine is off as well, but to be honest I believe you woul need to have an element of bad luck for the a ball to fall out. If the bike was on its side it would not have fallen out.
That being said it is worth opening her up and making sure. It is not a big job and you will be able to set the of slack properly
Well, I tugged on the rod a bit and it is nice and snug. I just pulled enough to feel the tension, but not move it. There's enough tension that I don't think I moved it during disassembly. I wouldn't have pulled it that hard. I think what happened is I moved the bracket, but since the stud is broken, it just fell out.
If I did lose a ball, how will I know? Can I start the bike and then tell somehow, or is the only way to be sure to pull the cover?
If I did lose a ball, how will I know? Can I start the bike and then tell somehow, or is the only way to be sure to pull the cover?
Jim Cook
Platinum Level Site Supporter
I doubt you lost a ball without taking the pv governor apart.
I have welded the stud back onto the pv bracket before, with good results.
I first drilled the depression where the stud broke free of the bracket, to let me weld it on the "back" side. This let me do all the welding on the back side, as there is not much clearance for such on the "front" side. I used a small welding tip in my acetylene torch and used a very thin mild steel filler rod.
If you do this, be careful to align the stud properly. It is critical to smooth operation.
My GasGas Factory tech sessions told me to heat the nylock nut on the stud before removal, to keep from breaking the stud away from the bracket, and always use a new 5mm nylock nut each time I reassembled it.
Good Luck and Good Riding!
Jim
Anglosaxon
New member
Have had the powervalve rebuilt with new plate/bearings etc after finding the original was totally butchered.
Still have, what I would describe as, a loud ?clacking? noise.
Is this the noise the pv tension fix should stop ??
Person who did the pv rebuild has stated he left a bit of ?tolerance? there which may account for still having the LOUD noise.
Still have, what I would describe as, a loud ?clacking? noise.
Is this the noise the pv tension fix should stop ??
Person who did the pv rebuild has stated he left a bit of ?tolerance? there which may account for still having the LOUD noise.
Jakobi
Super Moderator
IME, these engines make noise.
The powervalve flapper has a heap of tolerance in it, if it didn't it would bind up and need cleaning more frequently.
The clutch packs can make noise, the pistons can slap around a bit too. An alloy bash plate will redirect everything back up at you.
Add in a few vibrations, sloppy plastics, rad braces, a slightly misaligned pipe, and you get a symphony of sound.
Loosen the chain a bit and hear that slap too!
The powervalve flapper has a heap of tolerance in it, if it didn't it would bind up and need cleaning more frequently.
The clutch packs can make noise, the pistons can slap around a bit too. An alloy bash plate will redirect everything back up at you.
Add in a few vibrations, sloppy plastics, rad braces, a slightly misaligned pipe, and you get a symphony of sound.
Loosen the chain a bit and hear that slap too!
Just Squeaky- Gassers Have Character Like a Ferrari.
Don?t forget the clutch squeal. I have a rekluse clutch with a rekluse basket in my 2011 gasser. If I am a gear too high it will squeal like a pig. I have been riding it since 2011 and I have never ever had the slightest problem. I rode a 2018 gasser with a rekluse clutch, when I was a gear to high it would squeal exactly the same way as my 2011,otherwise in the correct gear the gassers never make a sound. My 94 CR 250 has a Rekluse clutch with the torque drive plate system and a Rekluse Basket, it never makes a sound even if I am two gears too high. Go figure.
Don?t forget the clutch squeal. I have a rekluse clutch with a rekluse basket in my 2011 gasser. If I am a gear too high it will squeal like a pig. I have been riding it since 2011 and I have never ever had the slightest problem. I rode a 2018 gasser with a rekluse clutch, when I was a gear to high it would squeal exactly the same way as my 2011,otherwise in the correct gear the gassers never make a sound. My 94 CR 250 has a Rekluse clutch with the torque drive plate system and a Rekluse Basket, it never makes a sound even if I am two gears too high. Go figure.
Jim Cook
Platinum Level Site Supporter
Don?t forget the clutch squeal. I have a rekluse clutch with a rekluse basket in my 2011 gasser. If I am a gear too high it will squeal like a pig. I have been riding it since 2011 and I have never ever had the slightest problem. I rode a 2018 gasser with a rekluse clutch, when I was a gear to high it would squeal exactly the same way as my 2011,otherwise in the correct gear the gassers never make a sound. My 94 CR 250 has a Rekluse clutch with the torque drive plate system and a Rekluse Basket, it never makes a sound even if I am two gears too high. Go figure.
What oil are you using in the transmission?
adriano.ro
New member
So,the best way to adjuts pv preload? Is there tips to do that?
Jim Cook
Platinum Level Site Supporter
Yes.
It is done at the governor, or bell crank which controls the pv movement as the revs rise.
The proper procedure has been described in detail on this forum.
You can find it with a search.
Similar threads
