Y.P.V.S. Need Help!

[jmp2204]

New to power valves, not new to Yamaha or wrenching,I just bought an 02 srx from a guy how kept it in nice shape cosmetically.Going over the sled after i got home (preseason check) i pulled out the power valves (to check for carbon) . looks like i have one broken cable and the other 2 are not attached to the valves(i assume the button on the end of the cable should go in the end (slot) of the valve. i'm thinking the cable has pulled through(broke the valve) am i correct? Is this due to lack of maint. (cleaning) 2 valves are like this ,the other that is good(pictured) has a broken cable.(any body have 2 valves for sale) can someone confirm my speculation or contradict it please........I have put about 5 miles on this sled with what i think are non functional valves will it hurt anything?

 

[Yamidude59]

if your valves aren't operating you will notice a lack of power, won't hurt anything, the point of powervalves is to adjust backpressure using the ignition sensor to calibrate the angle of the valve to control the backpressure during highspeed runs, hence keeping the powerband smooth throughout the rpms, if your valves are not working, there is power in that sled that is not being released. you will notice a difference once they are working.

 

[daman]

Your top valve in the pics are junk pulled through the other looks half pulled
not far behind,they can be repaired,,few of our members here do it.

it happened because the owner did not do proper maintenance and clean them when he should have,OR your cables where not adjusted right,you
need to pull and clean one or two times a season depending on mileage
and run a good full synthetic oil, and watch jetting..

 

[saskattakman]

i repaired mine....heres how i did it took them to a welding shop where they tig welded the crack shut...i then took a drill bit the same size as the hole drilled it out...then took a hacksaw with a fine tooth blade and cut the slot...then ground down the top of the valve so it looks like an original one....took some sandpaper and sanded the sharp edges where the cable goes into....worked for 1000 kms so far...and it didnt cost me anything lol its worth a try

 

[jmp2204]

Thanks for your help guys! Can anyone tell me if this peening on the chamfered edges on the sides is normal wear,exccessive wear,beyond what it should be to re-use if i weld the cable ends? What are these made of ,aluminum?

 

[jmp2204]

Thanks for your help guys! Can anyone tell me if this peening on the chamfered edges on the sides is normal wear?,exccessive wearbeyond what it should be, to re-use if i weld the cable ends? What are these made of ,aluminum?

 

[daman]

i don't see a problem,did they come out ok,,

 

[change_up]

Yes they are made of aluminum but there is a hard clear anodizing on them. You'll need to thouroughly clean them and then let the welder take the coating off and do any additional cleaning prior to welding it with a TIG

 

[jmp2204]

Thanks again guys! great site !

 

[Yamahasrx700]

If you end up buying new valves, I will take the old ones off your hands.

 

[jmp2204]

Daman, one pulled out with the use of vice gripes(no i did not clamp them hard) the other 2 ,by hand .There was alot of grunge on the back side of the valve (on the shoulders) .i was just wondering about the peening or roll over on the edges of the chamfer (about 1/2-1 mm) pictures are hard to see it (guess i didn't set my camera up right ,not bright enough)

I am going to replace them at seasons end ,but for now i am going to weld these ones( i am a welder ,but don't have access to a tig , but a buddy of mine does...Thanks for the replies guys!

 

[wantsnow]

what happens if the coating is completely stripped off the valve from a harsh cleaner. Are THE VALVES STILL USABLE OR IS IT JUNK?

 

[Yamidude59]

basically the coating is there so the aluminum does not oxidize (kind of a way aluminum "rusts") so it moves freely in there

 

[daman]

Also....

The coating is there to help prevent carbon from sticking to fast, with out it they'll gum up terrible,has to be on.