Author Topic: K75 Valve Adjustment Part #2  (Read 2853 times)

Offline MCRyder

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K75 Valve Adjustment Part #2
« on: June 15, 2019, 01:51:45 PM »
Got in the shims from Cycle-Re-Cycle.  My math got me ordering two 2.45 shims.  The #2 needed backing off, the new shim got it to the 25mm blade slipping in (could only get in a 23 before the adjust).  The #3 check was good at 25mm, but I felt is was good to back it off some.  The new shim made no difference in clearance, all I can still get in is the 25mm blade.  So both are on the tight end  So question - is it worth the time/trouble to get 2.40 shims to loosen them up further?

I'm riding up to the Missouri State Rally next weekend.  I figure with the clearances I'm getting now won't hurt to ride it up in current state.  Then get anal  :eek: and adjust the shims with 2.40 shims when I get back.

Thanks for any input.
Mark - East Texas
'14 Suzuki V-Strom 1000
'12 Aprilia Shiver
'92 BMW K75RT (#3)

Offline Laitch

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Re: K75 Valve Adjustment Part #2
« Reply #1 on: June 15, 2019, 02:56:47 PM »
The #3 check was good at 25mm, but I felt is was good to back it off some.  The new shim made no difference in clearance, all I can still get in is the 25mm blade.  So both are on the tight end  So question - is it worth the time/trouble to get 2.40 shims to loosen them up further?
You should be using go and no-go feeler gauge blades. I can't determine for certain your measuring technique from what you've written. For exhaust valve clearances, a 0.25mm blade is the go and a 0.30mm blade is the no-go, although clearances a few hundredths greater are acceptable for many riders. I don't know about anal riders because I avoid them. :giggles  Both those valves are not on the "tight end"; they are within spec. Valves clearances are either tight, loose or within spec. The replacement shim should have made a difference—at least 0.01 millimeter's difference. If it didn't, you likely measured incorrectly, but in my book, if the 0.25 blade passes through smoothly under an exhaust valve's cam, it isn't too tight.

If your valve clearances are currently what you represent them to be, enjoy the ride and don't be concerned with them.

When members are discussing clearance procedure, they should indicate the go/no-go measurements before shim replacement, the size of the shim being replaced in the assembly, the size of the shim replacing it and the tools they are using for measurement.
  • Along the Ridley in Vermont.
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Offline The Mighty Gryphon

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Re: K75 Valve Adjustment Part #2
« Reply #2 on: June 15, 2019, 05:26:59 PM »
If the valve clearance is tight, and you can read the number on the shim, just go one size thinner and you will be back in spec.  I could explain why this is true, but numbers make my head hurt which makes me cranky.  If you don't believe me, spend a few minutes thinking about what you're doing.  If not, that's okay too.
  • In my garage in Marilla, NY
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Offline Laitch

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Re: K75 Valve Adjustment Part #2
« Reply #3 on: June 15, 2019, 07:34:26 PM »
If you don't believe me, spend a few minutes thinking about what you're doing.  If not, that's okay too.
It's nice when you're not cranky.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles
I wept because I had no radials until I met a man who had no splines.
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Offline MCRyder

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Re: K75 Valve Adjustment Part #2
« Reply #4 on: June 15, 2019, 08:21:49 PM »
That's for the great tech info Laitch, it clears up a lot. 

The OEM shims didn't have the number, used a micrometer for measurement.  The shims I got had the numbers.

I don't do this job often, K75 tend to stay in spec and mine's got less than 40K on it.  So I tend to overthink it (does it show?  :giggles)
Mark - East Texas
'14 Suzuki V-Strom 1000
'12 Aprilia Shiver
'92 BMW K75RT (#3)

Offline Laitch

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Re: K75 Valve Adjustment Part #2
« Reply #5 on: June 16, 2019, 02:17:04 AM »
I don't do this job often, K75 tend to stay in spec and mine's got less than 40K on it.  So I tend to overthink it (does it show?  :giggles )
When you do this job, you should follow it with a throttle body balance.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

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