Author Topic: Advice please just purchased a 1986 k75s that was px in at the local showroom  (Read 2788 times)

Offline 1986 k75s

  • Curious
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In the local Honda Showroom today regretting the recent purchase of a suzuki gsf 650 bandit and the revvy nature it had when i noticed a k75s . My thoughts went back to my last BWW a K100 and of how relaxed that had felt on the motorway . The 75 was a C reg 1986 in brown which almost looked like black at first glance the S version with half fairing and showing 32,000 miles with all old Mot s . 5 minutes later and 800 handed over the keys were mine and she was jerkily ticking over on a small amount of choke outside the showroom . Crossing my fingers (sold with no warranty ) i selected first then second and so on and was pleasantly surprised at he relaxed nature of the bike and the fact it felt so much more agile than the bandit and lighter . Onto the motorway at Letchworth A1 and i took her up to 80 then 90 eased off and happily cruised at 70 down to Welwyn  then Hatfield i then took the Lower Luton road to Batford Harpenden when suddenly the bike lost all power . I hadnt checked the fuel before leaving and opened the cap up to see rather worringly fuel ?? The tank was low though and i tried to remember if these bikes had a reserve tap or switch over . I tried starting her again and she came to life so once again i started off as i came into Batford she lost power again i stopped then restarted and off i went again . At the fuel station i filled her right up and have had no repeated events for now .

So was wondering if this is a problem or just low fuel i couldnt find a tap so i presume the change over to reserve is automatic ? The tank isnt original being black so was also wondering if this maybe a contributing factor .

My second question it being a 86 is fuel and wether unleaded is ok for it ?

Any other advice on maintenance etc tips etc welcomed . I have fallen in love with the old girl lol.

Offline frankenduck

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There's no fuel petcock or reserve.  The low fuel light  in the lower left of the instrument cluster should come on when you have about 4L left.

It is designed to run unleaded fuel.

Read this thread if you're new to BMW K bikes
Once I had a Collie pup
Dug a hole and covered him up
Now I sit there by the hour
Waiting for a Collie-flower

Offline mystic red

  • Retired Professsional Driver
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When you say "lost power" do you mean all electrical power or the engine dies? More specific symptoms will give someone a chance to diagnose the problem. :yes

Welcome to the site. We'll get her going for you eventually. Most of the really helpful people here are too full of crab right now to think straight.

Offline Chaos

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  • Posts: 2558
  • Mars needs women!
A clogged fuel filter can cause loss of power from fuel starvation, easy to change, it is in the gas tank. Or it could be an electrical issue such as the hall effect sensor, which tends to cut out when hot.
  • sw ohio
1987 K75S    VIN 0231
Original owner, Original litter
200,000 miles (plus or minus) and 5 paint jobs
2012 Ural 2WD sidecar (BMW's bastard step child)