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My K75S needs Valve Surgery

burnszilla

New member
My K75S was serviced at Ted Porter's Beemer Shop yesterday. New front tire, valve adjustment and throttle body sync. 117,000 miles on the odometer. Ted found a problem with my exhaust valves...

Valve specs: Intake: .006 - .008 Exhaust: .010 - .012
My K75S: Intake: .007, .007, .006 Exhaust:.005, .008, .014 (before adjustment)
Exhaust shims on #1 and #2 are thin at 2.2mm and 2.1mm.
The previous valve adjustment 15K miles ago, the exhaust valves were way out too.

Something was wrong, so he did a compression test.
#1: 70, #2: 110, #3: 125 ... not good
Also found an air leak on #2 throttle body.

Next week he's going to do a full leak down test to see where the problem lies.
His guess was that I needed a head job with the valves replaced.
Costing around $1100. Ouch.

A while ago I did something stupid. I rode for about 3 days with my high altitude loop switch on, until I noticed it was on. Arrgh! Could the engine running lean have caused all this damage?

After riding my 87 K75C I notice how much better the engine performance is on the C than on the S. The S has a lumpy idle and is not as peppy.
 
My bike also had a problem with the middle exhaust valve. I don't think its from using the altitude plug for a couple days.

I didn't think the rebuild would be that bad, until I got to item 3:

1) $11 apiece for new guides
2) $14 apiece for new lead-free seats
3) $109 each for exhaust valves!! (this part was $38 four years ago)
4) $44 for a new head gasket
5) $200-ish for a repair shop to R&R the parts in the head
6) 3-4 hours to R&R the head on the bike

That's about $400 in parts and $500 in labor right there. I'd start looking for a used head (or entire engine) instead. Spare motors are cheap, and doing the replacement is quite simple.
 
Where is the high altitude switch at?? Never knew there was an operator manipulated switch for that.
 
Motorman said:
Where is the high altitude switch at?? Never knew there was an operator manipulated switch for that.
I took the wires from the loop and attached them to a switch I installed under the left fairing.
 
jdiaz said:
That's about $400 in parts and $500 in labor right there. I'd start looking for a used head (or entire engine) instead. Spare motors are cheap, and doing the replacement is quite simple.

The labor to install a used engine would be more I was told. Also when you buy a used engine, you don't know what your getting. You could inherit the same problems. :dunno
 
Burnszilla said:
After riding my 87 K75C I notice how much better the engine performance is on the C than on the S. The S has a lumpy idle and is not as peppy.



so does this mean i get the peppy bike this weekend?? :clap


i'm currently facing a possible main rear seal leak and at the end of summer, if i don't stop buring oil, new valve guides and rings, don't ya just wish these things would run forever without breaking..............
 
:cry

It might be easier if you were looking for a reason to rationalize a new(er) bike...
 
knary said:
:cry
It might be easier if you were looking for a reason to rationalize a new(er) bike...

Scott.. I tried.. "Hell hath no furry like my wife when she hears the letters GS."

djw just sent me a PM with an 87 engine in Long Beach, CA with 21,000 original miles on it for $500.. I think this is the way to go. Why replace the valves when you can do a whole heart transplant for the same or lower price.
 
Burnszilla said:
The labor to install a used engine would be more I was told. Also when you buy a used engine, you don't know what your getting. You could inherit the same problems. :dunno

A quick check of the IBMWR Marketplace found this ad:


1987 K75 S engine
K75S engine from wrecked bike with 21,000 orig. miles. No damage to engine, this whole thing has been sitting in my garage and needs a good home.
Price: $500 obo
Location: Lakewood CA.
Contact XXXXXXXXXXXXXXXXXX
Telephone XXXXXXXXXXXX
Posted Wednesday, April 12, 2006 at 23:10:17 (EDT)
 
BubbaZanetti said:
so does this mean i get the peppy bike this weekend?? :clap
I've been contemplating that same question.. I rode the C to work today.. The peppiness is really nice and it's way faster, but there's some kind of K75 class system affecting me. Once you ride an S it's hard to go down a level and ride the C. I don't feel as 'cool' on the C as I do on the S. :dunno Perhaps I have some issues.
 
Burnszilla said:
I've been contemplating that same question.. I rode the C to work today.. The peppiness is really nice and it's way faster, but there's some kind of K75 class system affecting me. Once you ride an S it's hard to go down a level and ride the C. I don't feel as 'cool' on the C as I do on the S. :dunno Perhaps I have some issues.



you don't have issues, i'd feel like a dork on an R11/1150R
 
GSTom said:
A quick check of the IBMWR Marketplace found this ad:
1987 K75 S engine
K75S engine from wrecked bike with 21,000 orig. miles. No damage to engine, this whole thing has been sitting in my garage and needs a good home.
Price: $500 obo
Location: Lakewood CA.
Contact XXXXXXXXXXXXXXXXXX
Telephone XXXXXXXXXXXX
Posted Wednesday, April 12, 2006 at 23:10:17 (EDT)
Thanks Tom.. the ball is rolling.
 
Burnszilla said:
I could fly you from Chicago to San Jose for $350. :)
Sounds like fun. I'm in!

Let's do it at DarrylRi's house. I think he's got a bike lift. :laugh
 
I still have to finalize with the seller, and pickup or ship..
Darryl's is a good idea.

I'll let you know of a good time later this month after I get the engine.
 
Burnszilla said:
Hey Kbasa... didn't something like this happen to your old K75??

Yeah. It was Tina's, actually. It had a cracked valve in it. Dunno how that happened. She rode it like, well, a girl. :ha


I'm so gonna get my ass kicked for that.
 
Good news. I got the engine in Lakewood for $400 and I have to pay for shipping. UPS quoted $76 for 100 lbs. to my door and ForwardAir quoted $82 from LAX to SFO.. SFO is 50 miles away.

So how much does this engine weigh so I can get a more accurate quote?
 
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