Maintenance & Technical > KX500 Original
how to i check the power valves
sandblaster:
There is a seal on that linkage shaft that may be worn out.
Also the shaft may be worn out and leaking air as well as the seal...
Air leaks are not good...
b4himdude:
wow id like to drop my couple cents worth of what o can share related to this topic. . sounds to me like its your first go round with these valves. gotta drain the coolant. and remove the barrel/jug. everybody has their way of what parts are left connected. but to me the tank the seat the plastics the carb, pipe and spark arrester /silencer are off the bike while im catching the coolant in a bucket. i find it so much easier to take off the six bolts and loosen 3 clamps to remove the radiator halves leaving the long hose connected to the water pump and the left sides connected to the radiator. then rather than remove the short hose above the water pump by loosening the clamp just drop the two bolts that secure the nipple to the cylinder jug, but remember the o-ring that seals the gap between the jug and that nipple when you separate the two. you dont want to have to look for it when it gets away accidentally. you dont have to take the radiator halves off but as i was getting to it makes it so much easier separating and reinstalling the cylinder jug. now you only have the spark plug four nuts on the jug base and a nut under the rubber boot that connects the governor arm to the power /exhaust valve assembly.(oh and the two bolts that fasten the plastic cover that protects the actuator rod end on the outside of the cylinder jug. slide the jug off and you dont have to but i personally would drain the transmission oil remove the kick starter rear brake pedal and remove the clutch cover. its a good time to look at everything not bottom end related right now. i mean s**t is time consuming and odds are youll have to replace the idler gear due to the carbon built up on the exhaust valve assembly , because in all reality that idler gear is the only thing that keeps the two valves in synchronized motion . and when the carbon gets too thick, the teeth of the idler gear are the first thing to feel the pain.any way theres really no simple way to get a carbon caked power valve assembly to come free once you get the screw that holds the seal in place and the 2 little tiny circlips that hold the end of the valve rod off. if you need any pointer on removing the two valve guides and idler guide all i can say is first and foremost before you take these out and think youve won the exhaust valves are marked on the top of the rods as to which one goes on which port. one of them , and i do believe its the rod on the right side(as you are holding the jug upside down exhaust side facing your belly) the valve that sits next to the idler gear has a little ring on the top of the shaft that indicates that is the valve that needs to go on that side..do not forget that. very important. now theres also the main exhaust valve. its like a damper that works in conjunction with the rod valves. thats whats under those two bolts that hold that little oval like piece of aluminum . take those two bolts out and you will have another two bolts inside holding that on place. once you get all this stuff out decarbonize the whole lot of it. if you dont have the clymer manual m447-3 it would be a good investment at this point . i have some literature if you would like me to send it to you but not something i should probably post on an open website. it has to do with the reassembly of the system. alignment of the valves and pushrod are crucial and the gears on the valves are marked with little dots. as well as there are also alignment lines marked on the pushrod.so this is where a picture would be best. just let me know ifyou need the literature and ill send directly to you.
alexander-vmann:
--- Quote from: b4himdude on August 31, 2015, 10:06:29 PM ---wow id like to drop my couple cents worth of what o can share related to this topic. . sounds to me like its your first go round with these valves. gotta drain the coolant. and remove the barrel/jug. everybody has their way of what parts are left connected. but to me the tank the seat the plastics the carb, pipe and spark arrester /silencer are off the bike while im catching the coolant in a bucket. i find it so much easier to take off the six bolts and loosen 3 clamps to remove the radiator halves leaving the long hose connected to the water pump and the left sides connected to the radiator. then rather than remove the short hose above the water pump by loosening the clamp just drop the two bolts that secure the nipple to the cylinder jug, but remember the o-ring that seals the gap between the jug and that nipple when you separate the two. you dont want to have to look for it when it gets away accidentally. you dont have to take the radiator halves off but as i was getting to it makes it so much easier separating and reinstalling the cylinder jug. now you only have the spark plug four nuts on the jug base and a nut under the rubber boot that connects the governor arm to the power /exhaust valve assembly.(oh and the two bolts that fasten the plastic cover that protects the actuator rod end on the outside of the cylinder jug. slide the jug off and you dont have to but i personally would drain the transmission oil remove the kick starter rear brake pedal and remove the clutch cover. its a good time to look at everything not bottom end related right now. i mean s**t is time consuming and odds are youll have to replace the idler gear due to the carbon built up on the exhaust valve assembly , because in all reality that idler gear is the only thing that keeps the two valves in synchronized motion . and when the carbon gets too thick, the teeth of the idler gear are the first thing to feel the pain.any way theres really no simple way to get a carbon caked power valve assembly to come free once you get the screw that holds the seal in place and the 2 little tiny circlips that hold the end of the valve rod off. if you need any pointer on removing the two valve guides and idler guide all i can say is first and foremost before you take these out and think youve won the exhaust valves are marked on the top of the rods as to which one goes on which port. one of them , and i do believe its the rod on the right side(as you are holding the jug upside down exhaust side facing your belly) the valve that sits next to the idler gear has a little ring on the top of the shaft that indicates that is the valve that needs to go on that side..do not forget that. very important. now theres also the main exhaust valve. its like a damper that works in conjunction with the rod valves. thats whats under those two bolts that hold that little oval like piece of aluminum . take those two bolts out and you will have another two bolts inside holding that on place. once you get all this stuff out decarbonize the whole lot of it. if you dont have the clymer manual m447-3 it would be a good investment at this point . i have some literature if you would like me to send it to you but not something i should probably post on an open website. it has to do with the reassembly of the system. alignment of the valves and pushrod are crucial and the gears on the valves are marked with little dots. as well as there are also alignment lines marked on the pushrod.so this is where a picture would be best. just let me know ifyou need the literature and ill send directly to you.
--- End quote ---
ok i think i should be able to get the cylinder of(i have done it on four strokes) but for the powervalves im going to have to look on youtube,(i have a mild autism and having visual instructions makes it much easier for me)
b4himdude:
you know what before i had the the clymer m447-3 manual i looked all over the web. utube doesnt have squat that is going to help you. there is a site that offers some information its (my spelling is not exactly right but its called ) keustermanns.youll find some information there. also google kx500 shop manual and if you do a little scrolling or try another key word other than shop manual maybe service manual or related you will find a FREE pdf downloadable base service manual with supplemental chapters that cover the things that changed from year to year. like i said its free. if all that fails i have a scanner and all i have to do is scan the d**n page from the book and blank out any identifying marks as to who im infringing on. just tell me if it comes to that and ill do it post haste., ya im sure you can remove the cylinder . if you dont already have one make sure you have a thin walled 14 mm 6pt(hex) box end wrench. oll be d**ned if i know how the hell a person os supposed to correctly torque 3 of those cylinder base nits but i guess if you do the one you can then get a feel for how tight that nut is with the box end 14mm you can kinda get her close. just snug the other 3 nuts before torquing the 1 you can get a socket on. let me know and any questions you may have several of the veterans here know some things i may not. but this kips exhaust valve mechanism was the subject that led me to this site and ultimately drove me to become a member. so im pretty savvy with this part. funny thing is i had the clymer manual and took the d**n thing apart and reassembled it the same way 3 times before sandblaster and fox4beaver got it through my head its time to search for the problem i was having elsewhere. the first time you remove the valve guides its going to take all the patience you have to get them out if carbon is built up to the degree it sounds like it is.pb bolt breaker wd40 wiggle the thing. start with the guide that has the half moon shape up0 next to the other guide. try forcing some compressed air up into the valve ports to push the guides out. the 2 full circle guides have rubber o-rings so be careful. just a warning try not to put pliers on the valve shaft ends you can see sticking out from the guides. if you scar them even just a little bit the will hang up upon reassembly and youll feel you need to force the guides over them to seat. but if that does become the case just take some fine sandpaper to the areas you scarred trying to remove them . get em so thee guides just drop right over them smoothly without any resistance.AND REMEMBER THE VALVE NEXT TO THE IDLER GEAR IS MARKED NEAR THE END OF THE SHAFT WITH A RING AROUND IT. THAT ONE MUST BE REPLACED WHERE IT CAME FROM. GOOD LUCK
alexander-vmann:
Does the clymer you talk about cover the 1987 engine to?
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version