correction: 1988 vs. 1992 fuel tank

[traderpro2003]

In a previous thread, some have suggested grinding the valve stems for proper/additional clearance. I'm curious if anyone has actually done this. The shop manual specifically states not to do it, but in practice does it really happen? If not, how would you correct the problem without replacing the entire cylinder head? From the Kawasaki repair manual: "Do not grind the valve stem end to repair it or to permit additional valve clearance. If the valve end is ground, the lifter may contact the spring retainer and/or split keepers during operation allowing the keepers to loosen. Consequently, the valve may drop into the engine causing serious damage."

[Jeff Saline]

On Mon, 18 Aug 2008 17:32:22 -0000 "traderpro2003" writes:

> In a previous thread, some have suggested grinding the valve stems > for > proper/additional clearance. I'm curious if anyone has actually > done > this. The shop manual specifically states not to do it, but in > practice does it really happen? If not, how would you correct the > problem without replacing the entire cylinder head? > > From the Kawasaki repair manual: > "Do not grind the valve stem end to repair it or to permit > additional > valve clearance. If the valve end is ground, the lifter may contact > > the spring retainer and/or split keepers during operation allowing > the > keepers to loosen. Consequently, the valve may drop into the engine > > causing serious damage."

<><><><><><><><><><><> <><><><><><><><><><><> Brian, Not all valves can safely be ground. Some contain sodium or are aluminized. Some are also so worn that even if they are of a type that can be ground they would be out of specs after grinding. There are a lot contact areas that must be considered in a valve system. Contact area of the valve face is important for heat transfer. Changing that changes how deep a valve sits in a head. On the other end the valve stem will move out the deeper the valve is in the head. That removes clearance between the end of the stem and the actuating mechanism. Having a stem sit too high in the head will also change the spring height as the keeper moves with the stem. This is going the opposite of having tight valves which move the valve face too far from the valve seat reducing heat transfer while extending the time the valve is open (duration). Some valves can safely have the face ground or the end of the stem ground to adjust to proper clearances. Shims can be placed under valve springs to adjust spring height. But not on all applications. Valve seats in the head can also be ground but only a small amount. Once they have reached a limit they must be replaced either by replacing the seat if possible or replacing the head. It looks like the KLR valves cannot safely be ground according to your reference. Valve seats can usually be replaced if the machinist knows what they are doing. New seats can return valve depth to the correct specifications which will move the valve further out of the head. That in turn will lower the stem height on the other side of the head again allowing proper clearance (which is adjusted by shims in the KLR engine). So if your valve seats are too deep from excessive grinding they may need to be replaced. But if the seat isn't replaced correctly it can work loose and if a seat comes loose in operation it can allow the valve to stick open contacting the piston (a bad thing) or break into pieces damaging the piston, cylinder wall or head. Or maybe nothing worse happens than the engine quits running and you have to get it replaced again. Replacement seats must also be of the correct material for the application. BMW Airheads in 1981-1984 had an incorrect material used which caused premature valve failure. Once the correct valve seats are installed the problem goes away. Some folks refuse to replace the valve seats and instead end up replacing valves every 50,000 or so miles. This just barely touches the surface of valve info. If I had a head in the shape that your's seems to be in I'd be calling Cary at Schnitz and asking him if he could help me. Best, Jeff Saline ABC # 4412 South Dakota Airmarshal Airheads Beemer Club www.airheads.org The Beautiful Black Hills of South Dakota 75 R90/6, 03 KLR650, 79 R100RT ____________________________________________________________ Need cash? Click to get a cash advance. http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3mKetHZVlDUDiOpHlpc5sXxKzSz9wJobUJFWyYZ5L9oD9WoU/

[traderpro2003]

Jeff, thanks for the very informative response. I'm going to wait for one more clearance check/inspection and I'll post the results. Too much riding left in the season. Maybe in the winter I'll pull the head and Cary will be my first call. This group has been tremendously helpful educating me here. Again thanks to you and others - Brian

--- In DSN_KLR650@yahoogroups.com, Jeff Saline wrote: > > On Mon, 18 Aug 2008 17:32:22 -0000 "traderpro2003" > writes: > > In a previous thread, some have suggested grinding the valve stems > > for > > proper/additional clearance. I'm curious if anyone has actually > > done > > this. The shop manual specifically states not to do it, but in > > practice does it really happen? If not, how would you correct the > > problem without replacing the entire cylinder head? > > > > From the Kawasaki repair manual: > > "Do not grind the valve stem end to repair it or to permit > > additional > > valve clearance. If the valve end is ground, the lifter may contact > > > > the spring retainer and/or split keepers during operation allowing > > the > > keepers to loosen. Consequently, the valve may drop into the engine > > > > causing serious damage." > <><><><><><><><><><><> > <><><><><><><><><><><> > > Brian, > > Not all valves can safely be ground. Some contain sodium or are > aluminized. Some are also so worn that even if they are of a type that > can be ground they would be out of specs after grinding. > > There are a lot contact areas that must be considered in a valve system. > Contact area of the valve face is important for heat transfer. Changing > that changes how deep a valve sits in a head. On the other end the valve > stem will move out the deeper the valve is in the head. That removes > clearance between the end of the stem and the actuating mechanism. > Having a stem sit too high in the head will also change the spring height > as the keeper moves with the stem. This is going the opposite of having > tight valves which move the valve face too far from the valve seat > reducing heat transfer while extending the time the valve is open > (duration). > > Some valves can safely have the face ground or the end of the stem ground > to adjust to proper clearances. Shims can be placed under valve springs > to adjust spring height. But not on all applications. Valve seats in > the head can also be ground but only a small amount. Once they have > reached a limit they must be replaced either by replacing the seat if > possible or replacing the head. > > It looks like the KLR valves cannot safely be ground according to your > reference. > > Valve seats can usually be replaced if the machinist knows what they are > doing. New seats can return valve depth to the correct specifications > which will move the valve further out of the head. That in turn will > lower the stem height on the other side of the head again allowing proper > clearance (which is adjusted by shims in the KLR engine). > > So if your valve seats are too deep from excessive grinding they may need > to be replaced. But if the seat isn't replaced correctly it can work > loose and if a seat comes loose in operation it can allow the valve to > stick open contacting the piston (a bad thing) or break into pieces > damaging the piston, cylinder wall or head. Or maybe nothing worse > happens than the engine quits running and you have to get it replaced > again. Replacement seats must also be of the correct material for the > application. BMW Airheads in 1981-1984 had an incorrect material used > which caused premature valve failure. Once the correct valve seats are > installed the problem goes away. Some folks refuse to replace the valve > seats and instead end up replacing valves every 50,000 or so miles. > > This just barely touches the surface of valve info. If I had a head in > the shape that your's seems to be in I'd be calling Cary at Schnitz and > asking him if he could help me. > > Best, > > Jeff Saline > ABC # 4412 South Dakota Airmarshal > Airheads Beemer Club www.airheads.org > The Beautiful Black Hills of South Dakota > 75 R90/6, 03 KLR650, 79 R100RT > ____________________________________________________________ > Need cash? Click to get a cash advance. > http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3mKetHZVlDUDiOpHlpc5 sXxKzSz9wJobUJFWyYZ5L9oD9WoU/ >

[Andrus Chesley]

--- In DSN_KLR650@yahoogroups.com, "vtville" wrote:

> > I made a mistake in my previous message. I am wondering if a 92 > KLR650 fuel tank will fit on the 88 KLR 650. > > Any idea? > > Kawasaki is giving me no help on this one. >

I'm pretty sure that all fuel tanks from 88 when they came out with the KLR 650 to 2007 are the same cept for color. I have a friend whom put an 89 tank on an 00 for he like the color better. Andy in Louisiana KLR650 Bandit1250S