Valves n Shims...

[Missile99]

Steve?? Who the heck is "Steve"???

Spreadsheet info is found below.

.

It's this guy around here with no name. I think he's some kind of GS wizard or something.

Missile, I like the way you do your specs.
Neater and with less/no oil stains on the sheet.
I just do before and after specs. for each of my bikes and mic them also.

Eric

Thanks Eric. Somehow I managed to keep oil away. The bucket tool never slipped.


Ghost, I found the valve check/adjust to be simple and even somewhat enjoyable. The worst part was cleaning the friggin' gasket surfaces.

[mvalenti]

As I read thru the pages of information regarding valves and shims. A question keeps popping up. as the valve wears, it seats deeper/tighter. When you reshim you are adding thickness to fix this problem. Doesnt this now not let the valve seat completely? Or if it gets to this point a new valve is required?

[Missile99]

As I read thru the pages of information regarding valves and shims. A question keeps popping up. as the valve wears, it seats deeper/tighter. When you reshim you are adding thickness to fix this problem. Doesnt this now not let the valve seat completely? Or if it gets to this point a new valve is required?

The valves do tighten up, yes. When you adjust your clearances you almost always reduce the shim thickness, allowing the valve to seat completely. If you're at a point where you're putting in a really thin shim, then maybe you would consider doing valves. From what I've read around here, it would take some serious mileage or neglect to get to that point.

[mvalenti]

The valves do tighten up, yes. When you adjust your clearances you almost always reduce the shim thickness, allowing the valve to seat completely. If you're at a point where you're putting in a really thin shim, then maybe you would consider doing valves. From what I've read around here, it would take some serious mileage or neglect to get to that point.

the valve wears, the valve stays "open" with the thick shim, and a thinner shim is needed to "close/seat" it propper... OK I think I have it....

Now, what about decarburizing the pistons/heads? Do any of you treat at this point with sprays or additives?

[Missile99]

the valve wears, the valve stays "open" with the thick shim, and a thinner shim is needed to "close/seat" it propper... OK I think I have it....

Now, what about decarburizing the pistons/heads? Do any of you treat at this point with sprays or additives?

You said it well. The valve wears in and the thick shim hangs it open, reducing compression. Speaking of which, if when you check your compression the numbers are good then I wouldn't worry about cleaners or additives. The way I clean up carbon is to run to 9500 r's at every shift. That should do it. My $.02. Others here may have a different solution.

[mvalenti]

Took a ride, 15 minutes or so to warm up the bike brought it home to run the compression check. Pulled all wires, bumped the starter. #1 @115 #2 and #3 @90,#4 at 105...

[Steve]

If all checks out and compression is fine, would I still want to do the shims? I'm thinking yes....

Good thinking.

By the time the compression goes down, it's too late, the damage is already done. May as well adjust the valves and prevent the damage.

Pulled all wires, bumped the starter. #1 @115 #2 and #3 @90,#4 at 105...

Not all that bad, did you have the throttle held open?

.

[mvalenti]

I didn't do it when it was running, I pulled all the wires and bumped the starter till the guage maxes out. I predict I did it wrong..

[Guest]

It's this guy around here with no name. I think he's some kind of GS wizard or something.




Thanks Eric. Somehow I managed to keep oil away. The bucket tool never slipped.


Ghost, I found the valve check/adjust to be simple and even somewhat enjoyable. The worst part was cleaning the friggin' gasket surfaces.

I agree Eric, I rather enjoy that as well. I've helped several folks do their valves over the years. These days I don't ride enough to need to check mine often, so helping someone else helps me stay up on the process. Ray

[Guest]

I didn't do it when it was running, I pulled all the wires and bumped the starter till the guage maxes out. I predict I did it wrong..

If you don't keep the throttle open when checking compression, you will likely see lower numbers . You may be in good condition ring and piston wise with the numbers you saw, with a closed throttle. Ray

[mvalenti]

Thanks, I will pop the wires back on and repeat, this time running.

[Steve]

NO!! No need to have it running, just hold the throttle open while you are cranking it.

If the throttle is closed, the cylinders can't draw in enough air to compress, giving false low readings.

Just leave the wires off, leave ALL the plugs out, hold the throttle wide open, press the starter button and watch the gauge.

.

[mvalenti]

Whew good catch will do

[Missile99]

Let us know what you find out mvalenti. Sounds like you'll be in good shape if you hold the throttle open while checking. Certainly adjust your valves next. Re-check the compression if you're curious.

I checked my compression the other day. I started at low rpm, low speed in 2nd gear. Then twist the throttle. I determined that this aspect was good because the torque pulled the bike nicely, then at about 5k rpm the engine went bonkers and ripped toward redline. No weak feeling the whole way through the revs. I suppose the sweet, deceiving acceleration from good torque is more pronounced with the larger cc engines. Not fair.
Just kidding, the 550 is a blast.

No seriously, how is the torque pull out of the 850+ cc engines?

[tkent02]

No seriously, how is the torque pull out of the 850+ cc engines?

It's better than the smaller bikes, but wait until they hit 8,000 or so, that's what they were designed for.