Valve Adjustment Problem | Page 4 | GTAMotorcycle.com

Valve Adjustment Problem

gmang35 said:
I have the factory service manual. Has nothing in there about valve installed height.
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The service manual doesn't explain every possible way in which parts can fail.

Measure the depth of the top of the valve tip below the top rim of the retainer (around where the shim sits). Easy to do with even the cheapest digital vernier. Measure this dimension for several of the valves. If the valve in question gives a measurement substantially different from the rest of them ... there is a problem. Whether it's because the keepers are beating up the groove in the valve stem, or the keepers are beating up the conical recess in the retainer, requires disassembly and inspection.

Be glad you caught this before it went catastrophic.
 
The measurements I got for the other three valves were 1.8mm 1.8mm and 1.94mm. For the valve in question I got 2.34mm
 
That is too much difference. It means the retainer/keepers are pushing their way off the end of the valve. Needs to come apart to figure out why.
 
Hopefully the head isn't damaged in any way. I'm not really sure what you mean but I'm sure my friend will know lol.
 
Retainers can break but I've yet to hear of one stretching. Because your valve seats and faces look okay form the pictures, I'd go with Brian's assessment. The keepers are wearing down the groove that they sit in and as a result pushing the retainer up. If that is indeed the case, your cylinder head is most likely undamaged.
 
Probably just need a new set of keepers. They are softer than any of the other parts, and once it's apart I think you'll see that the valves and retainers will be fine. But I'd still check the springs very carefully. The factory service manual should have installed heights in the torque values and tolerances section. At least they used to.
 
If it is the retainers/keeprs, replace them all. Aftermarket ones are highly reccomended from almost if not all capable builders that deal with Gsxr motors.
 
If your lucky yoshimura was having a close out sale on them and they're still available. I ended up buying mine from APE.
 
Its not the retainers, its the valves. You should change the retainers anyway, but its the valves and they need to be changed. Consider yourself lucky that you didn't drop one into the cylinder. Unfortunately, they're not exactly cheap.
 
phil_si said:
Its not the retainers, its the valves. You should change the retainers anyway, but its the valves and they need to be changed. Consider yourself lucky that you didn't drop one into the cylinder. Unfortunately, they're not exactly cheap.
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How do you know this?
 
Considering it's my bike and I had it checked with my mechanic and he deems it to be the retainers after checking them at his machine shop. I'd have to say it's the retainers and not the valves. But what would I know, I only own the bike.
 
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