Author Topic: k75 valve maintenance  (Read 6960 times)

Offline burntstick

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k75 valve maintenance
« on: December 05, 2017, 05:47:14 PM »
91 k75rt 140000kms alberta,can
Previously loved bike with unknown valve maintenance. Should valve clearance be checked? Are burnt valves common on bike? How many valves per cylinder do i own ?
Thanks heaps!
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Offline Chaos

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Re: k75 valve maintenance
« Reply #1 on: December 05, 2017, 06:06:39 PM »
Valves are very easy to check and you should do it pronto.  Tight valves will burn.  The problem is these bikes will go long periods not needing an adjustment so people forget about checking them.  All K75's are 2 valve. 
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Offline burntstick

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Re: k75 valve maintenance
« Reply #2 on: December 05, 2017, 07:09:49 PM »
Thanks merry Christmas!
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Offline stokester

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Re: k75 valve maintenance
« Reply #3 on: December 05, 2017, 08:11:38 PM »
Valves are very easy to check and you should do it pronto.  Tight valves will burn.  The problem is these bikes will go long periods not needing an adjustment so people forget about checking them.  All K75's are 2 valve.
Yes, do it.   I had checked my right after I got my 40k K75 finding them within specs.  Fast forward 30k and I checked them again to find the exhaust valves on #1 and #2 with almost no clearance to the cam.  Searching on this site I found that cold-bloodedness or slow warm-up is a sign of this as the valves do not spend enough time on the seat to transfer heat.


The tools to change them are available from Ken Lively which is what I use and shims are used on some Japanese bikes as well.



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Offline burntstick

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Re: k75 valve maintenance
« Reply #4 on: December 05, 2017, 08:15:25 PM »
Thanks nick
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Offline The Mighty Gryphon

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Re: k75 valve maintenance
« Reply #5 on: December 05, 2017, 11:37:14 PM »
You don't need any special tools to check the valves, only to change the shims.  Pop the valve cover and check them.  All you need is a set of feeler gauges.  Do it as part of a spark plug change.  The plugs are easier to change with the cover removed, and the engine is easier to turn with the plugs out.

You should be able to check them and change the plugs in under an hour.  Beyond the the plug wrench, allen wrench and a wrench to turn the cam, a pan to catch the oil that comes out when the valve cover is removed.
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Offline burntstick

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Re: k75 valve maintenance
« Reply #6 on: December 06, 2017, 12:30:29 AM »
I appreciate the tips m.g.
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Offline MCRyder

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Re: k75 valve maintenance
« Reply #7 on: December 12, 2017, 09:46:35 PM »
I did a valve check on my RT recently.  It took more time to remove fairing panels then to do the check.  I used this vid as a tutorial, very helpful.  Hope you don't have sensitive ears, Chris's language gets a bit rough  :yes


Mark - East Texas
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'12 Aprilia Shiver
'92 BMW K75RT (#3)

Offline TX brick

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Re: k75 valve maintenance
« Reply #8 on: December 13, 2017, 05:41:05 AM »
Contrary to the remarks on the above video, my K75 valves have needed adjustment. A reduced hot idle speed is an indication of tight exhaust valves.
Ron

91 K75RT

Belton Tx

Offline Scott_

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Re: k75 valve maintenance
« Reply #9 on: December 13, 2017, 06:48:08 AM »
Another suggestion is to check the valves BEFORE you remove the spark plugs.... reason being, the process of removing the spark plug has the potential of breaking loose any carbon deposits near the plug and that then creates the potential situation of the loose carbon getting stuck in an exhaust valve opening and skewing your results.

Chances of this happening are low, but apparently it has happened with some as it is suggested by BMW in the service manuals.
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Offline burntstick

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Re: k75 valve maintenance
« Reply #10 on: December 13, 2017, 12:53:36 PM »
Good one ! Thks
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Offline technostructural

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Re: k75 valve maintenance
« Reply #11 on: December 18, 2017, 04:20:13 PM »
I checked mine in June of this year, and I found them all to be a tad loose. I took Chris Harris' advice and left them the F&*K alone.
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Offline blackie1

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Re: k75 valve maintenance
« Reply #12 on: December 18, 2017, 11:34:20 PM »
in a post above The mighty gryphon says  "Pop the valve cover and check them." 

do you need to replace the valve cover gasket every time you remove the valve cover or only if it is torn or perished etc
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Offline Martin

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Re: k75 valve maintenance
« Reply #13 on: December 18, 2017, 11:54:39 PM »
Replace only if damaged, a light smear of Three Bond 1104 liquid rubber gasket will reseal it. Allow time for it to set.
Regards Martin.
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Offline blackie1

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Re: k75 valve maintenance
« Reply #14 on: December 19, 2017, 02:01:49 AM »
thanks martin
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