power valve - real world photo- is this set too high?
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power valve - real world photo- is this set too high?
I might just be a numpty... but not sure of my powervalve alignment marks...
here's the non AR ie mark 3 an earlier piccy... ( from Knackered's FAQ post)

here's my mk 3 ---- is the alignment mark the vague line on the left of the casing ? ( in which case it sort of lines up??


video of it working ------> https://www.dropbox.com/s/m6m667xz1wi8u5g/IMG_3394.MOV
here's the non AR ie mark 3 an earlier piccy... ( from Knackered's FAQ post)

here's my mk 3 ---- is the alignment mark the vague line on the left of the casing ? ( in which case it sort of lines up??


video of it working ------> https://www.dropbox.com/s/m6m667xz1wi8u5g/IMG_3394.MOV
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong
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Re: power valve - real world photo- is this set too high?
I read the 2nd to last post which basically said mark the power valve full open position - by removing exhaust - pushing powervqalve wide open and markign where that is..
then run engine - thrash bollox of it - an make sure PV hits that wide open mark
thing is my problem is low to mid throttle.. full power is quite satisfying...
I did tweak PV a bit and now it feels like the engine is holding back mid throttle - then BAM - wide open power springs in..
PV or set needle height? ( mid throttle would be needle as opposed to jets right? )
then run engine - thrash bollox of it - an make sure PV hits that wide open mark
thing is my problem is low to mid throttle.. full power is quite satisfying...

I did tweak PV a bit and now it feels like the engine is holding back mid throttle - then BAM - wide open power springs in..
PV or set needle height? ( mid throttle would be needle as opposed to jets right? )
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong
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Re: power valve - real world photo- is this set too high?
Looking at the photo without even alignment marks you can see that's miles out, and this would explain why your bike feels more like a crosser, as in hesitant, then almost like a power band.
Get someone to confirm this as mine isn't the same, but you need to adjust it quite a bit. This should be done when engine has warmed up, kick it over and then kill engine, then set the valve at where it rests. The ECU should return it to this position every time you kill then engine from then on.
Shaun.
Get someone to confirm this as mine isn't the same, but you need to adjust it quite a bit. This should be done when engine has warmed up, kick it over and then kill engine, then set the valve at where it rests. The ECU should return it to this position every time you kill then engine from then on.
Shaun.
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Re: power valve - real world photo- is this set too high?
Looking back, I could be wrong, I'm just looking at the amount of thread and trying to compare to the diagram. Steve (knackered) may explain in detail, I'm sure I remember him cutting his down to give more PV operation.
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Re: power valve - real world photo- is this set too high?
I set mine according to your second post - Find the fully open point and make sure it goes that far but no further when revved.
If there is hesitancy after setting the PV like this then there is most likely to be a small jetting problem.
Have you watched the PV opening and closing? - I assume it has a smooth action as the revs build up?
If there is hesitancy after setting the PV like this then there is most likely to be a small jetting problem.
Have you watched the PV opening and closing? - I assume it has a smooth action as the revs build up?
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Re: power valve - real world photo- is this set too high?
thanks for the comments! the on/off powerband sensation can be quite exciting,, threw me into some bushes actually...
yeah I did watch it opening and closing.... a bit unsure as I only ever looked at mine....
here's the video link to my PV in action again...
https://www.dropbox.com/s/m6m667xz1wi8u5g/IMG_3394.MOV
before I take exhaust off ( typically shops have just closed for Chinese New Year - not open for 5-6 days - so no spare gasket to hand.. )
might have a play with the cable adjustment - what u reckon up a bit or down a bit?
yeah I did watch it opening and closing.... a bit unsure as I only ever looked at mine....
here's the video link to my PV in action again...
https://www.dropbox.com/s/m6m667xz1wi8u5g/IMG_3394.MOV
before I take exhaust off ( typically shops have just closed for Chinese New Year - not open for 5-6 days - so no spare gasket to hand.. )
might have a play with the cable adjustment - what u reckon up a bit or down a bit?
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong
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Re: power valve - real world photo- is this set too high?
I would think that the LHS of the arm needs to be ~3mm higher at rest.
The LHS of the arm should be ~1-2mm from touching the casing at fully open. From what I can see the LHS end of the arm touches the casing when the PV is at its extreme movement..
The LHS of the arm should be ~1-2mm from touching the casing at fully open. From what I can see the LHS end of the arm touches the casing when the PV is at its extreme movement..
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Re: power valve - real world photo- is this set too high?
yeh now u mention it - it is touching
much appreciated!
much appreciated!

1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong
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Re: power valve - real world photo- is this set too high?
SOLVED!
and didnt have to take the exhaust off so
( and guess who will add marks when he takes the whole thing apart in a couple of months... living an a learning! )
Kung Hei Fat Choy! ( Wishing You a Prosperous New Year! )

and didnt have to take the exhaust off so

( and guess who will add marks when he takes the whole thing apart in a couple of months... living an a learning! )
Kung Hei Fat Choy! ( Wishing You a Prosperous New Year! )
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong