Author Topic: K75s CR by arthur229  (Read 1882 times)

Offline Arthur_229

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K75s CR by arthur229
« on: January 13, 2019, 01:39:41 PM »
hello,
as said in my introduction that i would start a topic on my k75.

got this 88 k75s off a friend for a bottle of wine. the engine fires up and runs but cant put any gears luckely stuck in neutral. worst case cenario some ebay shopping for a gearbox.

here is a foto with no work started



I have been striping her down




a little problem with the exhaust

a bit rusty

Its going to be a long journey before its back on the road.
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline Laitch

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Re: K75s CR by arthur229
« Reply #1 on: January 13, 2019, 02:20:18 PM »
got this 88 k75s off a friend for a bottle of wine. the engine fires up and runs but cant put any gears luckely stuck in neutral. worst case
Do you know if shifting failed while the original owner was riding it? Maybe the clutch isn't disengaging. Check that. Maybe you should warm up the transmission case, open the filler and drain ports, empty whatever is left in the case then refill it with 0.8L of warmed 80w90 trans fluid. Maybe you could gently work at rotating the rear wheel after you do all that, then try shifting. There are a few options left before getting into somewhere you don't need to go, yet.

You probably ought to check the valve clearances, assess the engine's compression and see if you can get the drive train working before you do further stripping of this relic.
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #2 on: January 13, 2019, 02:29:46 PM »
Do you know if shifting failed while the original owner was riding it? Maybe the clutch isn't disengaging. Check that. Maybe you should warm up the transmission case, open the filler and drain ports, empty whatever is left in the case then refill it with 0.8L of warmed 80w90 trans fluid. Maybe you could gently work at rotating the rear wheel after you do all that, then try shifting. There are a few options left before getting into somewhere you don't need to go, yet.

You probably ought to check the valve clearances, assess the engine's compression and see if you can get the drive train working before you do further stripping of this relic.

What I know is that the previous owner let the gearbox loose all the oil and that the clutch died.
He drove the bike from work to home without oil about 10 miles.

  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline Laitch

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Re: K75s CR by arthur229
« Reply #3 on: January 13, 2019, 02:50:08 PM »
What I know is that the previous owner let the gearbox loose all the oil and that the clutch died.
He drove the bike from work to home without oil about 10 miles.
:laughing-on-ground:
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline alexg

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Re: K75s CR by arthur229
« Reply #4 on: January 13, 2019, 02:59:58 PM »
Probably that did it, but before buying a new gear box, try to put it in gear w/o the engine running. If the thing shifts, there is a chance that the box is ok, and the clutch is stuck due to high humidity; humidity plus clutch pressure might have bonded the friction disk to flywheel with rust. Happens to me every winter, and Michigan in winter is much dryer than the UK.
  • Michigan
  • '93 K75S, 1975 BMW R75/6 & 1984 Yamaha RZ350
Alex G.

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #5 on: January 13, 2019, 03:23:53 PM »
greetings...

somebody may have removed the driveshaft to sell on ebay... that and fliuds may be all you need...

j o
Probably that did it, but before buying a new gear box, try to put it in gear w/o the engine running. If the thing shifts, there is a chance that the box is ok, and the clutch is stuck due to high humidity; humidity plus clutch pressure might have bonded the friction disk to flywheel with rust. Happens to me every winter, and Michigan in winter is much dryer than the UK.

Just opened the filler of the gear box and there was alot of creamy gunk
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline Laitch

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Re: K75s CR by arthur229
« Reply #6 on: January 13, 2019, 03:37:18 PM »
Just opened the filler of the gear box and there was alot of creamy gunk
Don't eat it, no matter how appealing it is. Clean it out and follow previous instructions.
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #7 on: January 13, 2019, 04:16:44 PM »
greetings...

spread that on crumpets and report back here...

im thinking the twerk converter needs charged...

j o
Will do, I'll tell you all if it needs a bit of sugar or salt

Next time I get free time ill continue the job
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline The Mighty Gryphon

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Re: K75s CR by arthur229
« Reply #8 on: January 14, 2019, 09:46:10 AM »
It sounds like the input and output shafts are ok. 

Is the shift lever moving, or is it stuck?   If it moves but doesn't change gears it's possible that the grub screw has loosened to where the shifter no longer moves the shift drum.  If that is the problem you should be able to fix it in a long day of work. 

I had a very loose grub screw on my first brick, and besides taking about 7 hours to fix it, it wasn't a bad job.  That included lubing the drive shaft, final drive and clutch splines along with the swing arm bearings and putting proper torque on all the fasteners back there. 

It would also be a good time to change the clutch o-ring and possibly the rear main seal on the engine.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue, '89 K100RS Special edition White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too
'89 K100RS SE

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #9 on: January 18, 2019, 05:36:16 AM »
A small update on the gearbox, I drained the gear box of what was left of the oil and on the plug there was bits of metal. So there must be something broken inside. More updates to come as soon as I get more free time. And when trying to move the lever can hear somthing like metel grinding.
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline The Mighty Gryphon

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Re: K75s CR by arthur229
« Reply #10 on: January 18, 2019, 08:36:03 AM »
Is the lever stuck or does it move?   How far does it move?   Proper travel is about 2" or less. 
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue, '89 K100RS Special edition White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too
'89 K100RS SE

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #11 on: January 18, 2019, 08:53:01 AM »
Is the lever stuck or does it move?   How far does it move?   Proper travel is about 2" or less.
It doesn't move
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline The Mighty Gryphon

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Re: K75s CR by arthur229
« Reply #12 on: January 18, 2019, 09:16:01 AM »
Okay, it's probably NOT a grub screw problem. 

That may be good news, as that damn screw is a pain in the ass to get installed.   
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue, '89 K100RS Special edition White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too
'89 K100RS SE

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #13 on: March 14, 2019, 07:37:53 AM »
A small update, after thinking and plenty research I decided that will be maunting the k1100 gearbox and all of the material required for that mod.

  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #14 on: April 13, 2019, 07:50:17 AM »
Did the valves, they were massavly out f spec now tip-top condition. Soda blasted the engine and sprayed black with red details



* 20190413_085554.jpg (140.88 kB . 768x432 - viewed 149 times)
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline natalena

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Re: K75s CR by arthur229
« Reply #15 on: April 13, 2019, 09:45:14 AM »
Looks nice. Did you figure out the transmission issues? With luck, you'll have 2 or 3 sunny days of UK Spring to work on the bike. ;)
  • East of Joshua Tree
  • 1987 K75s #0919
On Holy Quest seeking Techron equivalent for splines.

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #16 on: April 13, 2019, 09:48:59 AM »
Looks nice. Did you figure out the transmission issues? With luck, you'll have 2 or 3 sunny days of UK Spring to work on the bike. ;)
Didn't bother opening it and just got another gearbox from a k1100
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988
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Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #17 on: April 23, 2019, 04:09:10 PM »
Another little update
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

Offline szabgab

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Re: K75s CR by arthur229
« Reply #18 on: May 09, 2019, 05:47:28 PM »
OK, looks nice. If you plan to turn the bike into a cappuccino, there are people out there hunting for spare parts, gauge clusters, indicators, mirrors, various bits and bobs :)
  • Budapest, Hungary
  • K75S 1985 model

Offline Arthur_229

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Re: K75s CR by arthur229
« Reply #19 on: May 18, 2019, 09:07:51 AM »
Got a great deal done lately, made my own exhaust manifold, fitted the k1100 gearbox, swing arm and final drive.
And almost forgot the rearsets.
  • London
  • Suzuki sv1000 and BMW K75s
London
K75s 1988

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