Author Topic: New to get back on the road... K75 RT 1995 UK bike  (Read 5813 times)

Offline lawtome

  • Motobrick Curious
  • Posts: 18
New to get back on the road... K75 RT 1995 UK bike
« on: April 27, 2020, 08:37:55 AM »
Hi all, I'll be looking for a lot of advice on getting my K75 up and running.
Came as a complete 1995 RT model with 67000 miles on it.

I've shed the very heavy fairing as it weighs a ton and was old, worn and damaged in places, and either needs a lot of repair and paint, or just getting rid of.

Keys-
The ignition was cut and hot wired by the seller to check it would work, only 2 wires twisted together, so would that work, would the other wires need connection.??  (he got it running with some spray into the airbox)
The bike has no keys, but I've done the drill mod to the tank cap and have gotten the old fuel out.

The coils are giving 3 fat sparks, as I run it with jump leads from my other bike. But I can't get it to fire up?
Seems like there's no fuel getting to the injectors, which may be clogged, but I can't get them out of the engine and am worried about braking them!
Could also maybe be the fuel pump, or fuel pump or injector relay maybe?

I got the bike to start to fire up but buy misting some fuel from a spray bottle into the air intake, but that gave a HUGE afterfire (backfire) through the air box, that blew the air box connecting ring off, and a whisp of smoke came out!
I'm hoping it'll be ok, and that I haven't bust the engine!!

Anyway wish me luck!

Tom.

  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline beemuker

  • ^ Quintessential Motobricker
  • Posts: 1110
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #1 on: April 27, 2020, 04:51:20 PM »
Good luck Tom; the rest of you , hold the comments until I can pop some corn and  chill a 6 pack.
  • Panama City, FL
  • '00 R1100RT,’92 K75 RT,past tense:'83 R80ST, '93 K1100LT,,94 R1100RS K75s, Honda NC700, Suzuki Bandit 1200, bmw R75/5 Honda 750

Offline volador

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  • Posts: 1165
  • NEEDS MORE CHROME
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #2 on: April 27, 2020, 05:54:02 PM »
Hi all, I'll be looking for a lot of advice on getting my K75 up and running.
Came as a complete 1995 RT model with 67000 miles on it...

I got the bike to start to fire up but buy misting some fuel from a spray bottle into the air intake, but that gave a HUGE afterfire (backfire) through the air box, that blew the air box connecting ring off, and a whisp of smoke came out!
I'm hoping it'll be ok, and that I haven't bust the engine!!
Anyway wish me luck!
Tom.

Welcome Tom

Thank you for Monday ROTFLMAO!

next attempt make a video I'll pay to watch that... keep up the brilliant work...

Some links for your K journey

Check parts compatibility with BMW MAX Microfiche, BOBS BMW, REAL OEM

https://shop.maxbmw.com/fiche/PartsFiche.aspx

https://shop.maxbmw.com/fiche/PartsSearch.aspx

https://parts.maxbmw.com/BMW___BmwMotorradK.html

https://www.bobsbmw.com/store/microfiche/BrowseSeries.aspx

https://www.realoem.com/bmw/select.do?kind=M&arch=1

https://www.ascycles.com/BMW-Motorcycle-Parts-Fiche

Cross reference parts like Bosch pn#'s, etc....  http://partsplusecat.com/
No spaces in the part number

Parts Vendors

https://www.beemerboneyard.com/

https://www.capitalcycle.com/

https://www.euromotoelectrics.com/

https://www.tills.de/

Headlight relay stuff if you chose to add one

https://www.motobrick.com/index.php?topic=268.0

http://www.motobrick.com/index.php/topic,4962.msg30932.html

http://culayer.com/product/matchbox-headlight-relay/

http://easternbeaver.com/Main/Wiring_Kits/H4_Kits/h4_kits.html
 Eastern Beaver site is a great reference for electrical connectors,plugs, etc...

http://www.k100-forum.com/

http://www.kforum-tech.com/Tech-page.html

http://www.kforum-tech.com/electrical/EFI/bike-wont-start-EN.htm

http://www.kforum-tech.com/Downloads/electrical/diagrams/interactive_diagrams.htm

http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/k100tshoot/K100.Troubleshoot.Start.2018.pdf

http://kbikeparts.com/index.htm

http://www.kbikeparts.com/classickbikes.com/ckb.tech/ckb.new2k.htm

http://www.kbikeparts.com/classickbikes.com/ckb.tech/ckb.tech.toc.htm

http://www.eilenberger.net/K75S/IgnitionSwitch/

http://www.verrill.com/moto/moto.shtml

this site has a lot of good info and breakdown pictures in the tech and tech resources sections for K1100 alot of the parts are on K75 & K100

http://www.k11og.org/forum/index.php?sid=2df953dde5715fd9001fbe69edec5ad0

https://ibmwr.org/index.php/k-bike-tech-articles/

This site has all kinds of technical specifications on all the BMW models    http://www.bmbikes.co.uk/mechanicalpages/kseriesmechanical.htm

http://largiader.com

http://bmwk10075abs1fix.web.fc2.com/index.html
  • NYC NY
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY  MAINTAINING THE OBSESSION

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #3 on: April 27, 2020, 05:55:29 PM »
Thanks for the support so far guys!
😜
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline volador

  • ^ Quintessential Motobricker
  • Posts: 1165
  • NEEDS MORE CHROME
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #4 on: April 27, 2020, 06:27:08 PM »
begin with http://www.motobrick.com/index.php/topic,11033.0.html

Spray or apply some penetrating oil, mineral spirits or kerosene to fuel injector ports to loosen them up, let sit overnight

Your afterfire (backfire) may have inadvertently damaged the Mass Airflow Sensor unit 'barn door' which located below the air filter in exploding air box

  • NYC NY
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY  MAINTAINING THE OBSESSION

Offline milq

  • ^ Proficient Motobricker
  • Posts: 225
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #5 on: April 27, 2020, 07:34:45 PM »
Don't let the magic smoke out of any electronic bits while you're in there!
  • Southern IL
  • 1988 K75S
Agree Agree x 1 View List

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #6 on: April 28, 2020, 02:44:22 AM »
Yeah, i know it was a dumbass move.
I’ve since found the incredibly informative pdf guide and will be going through that whilst trying to sort out what I’ve ruined through my dumbassedry.

I’m off to do some reading....
Cheers! 
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline Skunky

  • ^ SuperNatural Motobricker
  • Posts: 524
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #7 on: April 28, 2020, 03:25:56 AM »
Hi Tom,

Welcome to the Site.

You probably haven't broken the engine (that's almost impossible), but you may have damaged the MAF (but again probably not) These bikes are temperamental but Fn tough .

With regard to not starting there's lots of possible causes to look at first. Number one being the four way connector to the fuel tank. They are notoriously unreliable and can stop the fuel pump from running. The way to check is to press the starter and release straight away and you should hear the fuel pump turning over. If you don't just disconnect, clean the contacts with a good electrical spray and put back together. You may have to do it three or four times. There are a whole host of non starting threads on this forum where owners have replaced just about everything and found it was this connector after all. This is a great site full of useful information and will help you no end in your build. Use the search button on whole forum and you will find everything you need.

Good Luck

  • Derby GB
  • BMW K100lt
Rebuild it and they will come..
90 K100lt
Triumph Thruxton 900
Honda CB400F

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #8 on: April 28, 2020, 09:30:31 AM »
Might be reassuring to hear that it may not be totalled by my heavy hand!
I thought I might have bust a valve or something?

I've not had chance to go back to check on the bike as I am still working despite all the craziness going on in the world.
When I do though I will start a process of elimination on electrical connections and components to work out why I am getting no fuel.
I've been reading through the non starting threads and the pdf that someone has very usefully made.

I'll have to work out how to test the MAF I think.

Thanks everyone.
I'll update the post when I've info.
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline volador

  • ^ Quintessential Motobricker
  • Posts: 1165
  • NEEDS MORE CHROME
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #9 on: April 28, 2020, 11:42:00 AM »
Details steps for testing MAF  http://www.kforum-tech.com/electrical/EFI/bike-wont-start-EN.htm

this PDF is the above site page in 1 file  http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/k100tshoot/K100.Troubleshoot.Start.2018.pdf

If the moto has been sitting for some time you need to remove the petrol tank cap and have a look inside petrol tank

1-The petrol pump rubber vibration damper is known item to disintegrate with age and use making a bloody mess inside tank

2- tank needs to be cleaned of old petrol

3- If unknown when last change, the petrol tank fuel filter should be replaced.
Inspect the inner tank hoses probably old and brittle if never replaced. Inner tank hoses should be of the fuel submersible type hose designation

4- pull out the fuel injectors and have professionally cleaned or soak in lacquer thinner replace o-rings with Viton o-rings from Tills.de

5- charge battery should have a resting 12.6V or above

6- inspect-replace outer fuel hoses

7- inspect outer rubber bits and hoses especially the crankcase breather hose- 'Z' shaped hose' found towards the end of throttle bodies and exploding air box
and throttle body small rubber caps on tubing ports

8- check hoses to the Fuel Pressure Regulator found mounted behind the throttle bodies
    1-vacuum hose from throttle bodies to the bottom FPR
    2-middle hose from petrol fuel injection fuel rail
    3-top hose to petrol tank return line

9- add a pint or litre of kerosene to first few petrol tank fill-ups to clean system

more K-bike info Just bought a 2V
  • NYC NY
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY  MAINTAINING THE OBSESSION

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #10 on: May 01, 2020, 11:08:45 AM »
Thanks everyone.

Turns out that my K75 has a busted fuel pump.
I pulled the old pump out and have bench tested it and it's completely kaput.

I've ordered a replacement, along with a replacement fuel filter.
The inside of the tank is lovely and clean, although the fuel level sender rubber gasket is falling to pieces, so I've also ordered a replacement gasket too.

Whilst I'm waiting for the parts to arrive, I'm attempting to remove the injectors and am aiming at attempting to clean them, but have already located some replacement injectors if these are unsalvageable!
They are very stubbornly stuck in the engine at the moment. They were completely stuck fast, but lots of WD40 now has them all turning and rotating a little and will wiggle slightly from side to side.
I'm being gentle now to try to pop them out without them breaking.

Thanks.
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline Laitch

  • Faster than a speeding pullet
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Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #11 on: May 01, 2020, 11:58:22 AM »
I'm attempting to remove the injectors and am aiming at attempting to clean them,
I can't determine from what you've written whether you following this method, but if you aren't you probably should.
  • 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

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #12 on: May 01, 2020, 04:29:58 PM »
Yep.
That’s the method i have used.

Got them all out just now, and as advised there are clean cloth rags blocking the open injection ports on the engine now.
Thanks.
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline natalena

  • ^ SuperNatural Motobricker
  • Posts: 604
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #13 on: May 01, 2020, 04:48:32 PM »
Great to hear you're making progress. I'm still curious if your eyebrows are intact after the airbox incident. WD-40 is ok, but a few quid spent on Boeing T-9 and a penetrating oil of your fancy would go a long ways. Post pics when you can, and good luck with the injector's, don't bully them out. :)

oh, and Motobins Rocks!
  • MST
  • 1987 K75s #0919, '05 Sportster 1200C
We don't need no stinkin' moly.

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #14 on: May 19, 2020, 06:30:34 AM »
Hi all, I'm making a little progress on the bike....
I will sort some pictures at some point.

I've given the whole bike a proper clean up, & managed to pull the injectors out of the bike.
Wowzers! they were really stuck in!  :johnny

They were incredibly rusty old things.
I've carefully sanded down the rusty outsides of the injectors, and painted them so they shouldn't re-rust. Also cleaned the plastic parts carefully, along with the electrical connectors with contact cleaner.
I've cleaned out the injectors using a small 9v battery and then squirting high pressure injector cleaner through to unblock them. (all 3 were blocked)
I did that about 6-8 times on each injector, until they squirted consistently the same level.

As I said earlier i'd pulled out the fuel pump and bench tested it. It was busted!
I've since then replaced the Fuel pump, internal fuel lines and fuel filter. Along with the rubber gasket around the fuel level sender.
Then added fresh fuel to the tank. re-assembled as much of the bike as I could, then I wired up the bike to a battery and turned it over. It ran for 30 seconds or so.

Since then I've not gotten it to start up though, which is odd as the pump is running, electrics are good, spark was present last time I checked and fuel pressure is good to the injectors, with the injectors having been cleaned...

I'm going to try pulling the spark plugs to check them again, they were sparking fine, but I just want to be sure. And I'll also pull the injectors again to make sure they're not clogged back up again... I may need to buy new ones if they are?
Would you recommend original spec injectors or an alternative like the 4 hole jobbies?
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline The Mighty Gryphon

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Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #15 on: May 19, 2020, 08:08:10 AM »
Did you clean the rail? 

If not, chances are that it had old fuel and rust in it that has washed down to the injectors.

You might want to remove the rail and injectors.  Soak the rail for a couple days in vinegar followed by a good rinse and blow out with compressed air. 

The injectors are possibly plugged again.  I would do a reverse flush on them after removing the inlet filter screen.  You can get new screens for the injectors at an auto parts shop.

As far as four hole injectors, just realize that the orifices in those nozzles are 1/2 as large as the ones you just plugged.  Does that sound like a good idea?
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #16 on: May 19, 2020, 08:29:56 AM »
Sounds like a plan, a reclean of injectors and a deep clean on the rail is happening this weekend then.
And, yeah I think sticking with the standard injectors is the way to go. I've done a bit of research and the same conclusion has been suggested by other folks in regard to the 4 hole versions blocking up earlier.

Thanks for the quick reply.  112350
Cheers.
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #17 on: May 28, 2020, 05:01:25 PM »
Well, good news!
I got the old girl up and running.
15 years of sitting idle and she's finally back alive.

The engine seemed to run pretty well, there's a bit of a chattering sound coming from the clutch, I assume it's the clutch as it is coming from the rear of the engine, and it disappears instantly when the clutch is pulled in. It ran pretty well for 5 mins or so, but then cut out and seemed to require some revs to continue running. I ran it for about 20 mins in total but it required restarting a lot. And when it was running it would splutter and die unless the throttle was open a little. 
I'll have to look into that, but hey, success, it lives! 

  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline Laitch

  • Faster than a speeding pullet
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Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #18 on: May 28, 2020, 09:30:59 PM »
I assume it's the clutch.
I ran it for about 20 mins in total but it required restarting a lot. And when it was running it would splutter and die unless the throttle was open a little.
I'll have to look into that . . .
Assuming is a distraction. There are other several reasons for clatter. Post a video of the sound on YouTube and send us the link. Don't wobble the camera. Some of us are susceptible to vertigo.  :laughing4-giggles:

If you need throttle to keep it lit, that could be caused by vacuum leaks. Inspect the crankcase z-hose that attaches to the airbox; it might be cracked. Inspect the throttle body vacuum caps and the vacuum hose to the fuel pressure regulator for deterioration. If the engine runs and can be kept revving using the fast idle lever or the throttle screw—if there is one, some members have carefully sprayed carb cleaner or propane onto each throttle body rubber manifold. If the revs changed, it was a sign that the parts were leaking and needed replacement.
  • 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

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #19 on: June 10, 2020, 03:15:27 PM »
Thanks.
So I've bought replacement crankcase z hose and will be fitting that at the weekend.
Also bought a new battery.

Just had the bike running again whilst trying to investigate where any other air leaks might possibly be coming from.
Same as last time, the bike runs well enough but after about 5 minutes it splutters out.

One additional thing i noticed is that it appears to be raining inside my fuel tank..?!
Is it normal for fuel to be dripping down from around the fuel filler area inside the tank?
It looks to be coming from a small aluminium pillow shaped thing at the top just in front (toward the handlebars) of the fuel filler.
Sorry, it's quite hard to describe exactly where I mean.

If anyone can advise I'd be grateful. I have tried searching but can't find anything similar to this.
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline Laitch

  • Faster than a speeding pullet
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Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #20 on: June 10, 2020, 03:54:03 PM »
It looks to be coming from a small aluminium pillow shaped thing at the top just in front (toward the handlebars) of the fuel filler.
That's a vapor chamber. The return fuel line is above it so fuel simply spills into the tank. Later model Bricks have this vent and line arrangement.
  • 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

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #21 on: June 10, 2020, 03:59:37 PM »
Thanks Laitch.
Nothing to worry about then, it's just returning fuel from the fuel lines coming back to it's home in the tank.
phew!
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #22 on: June 26, 2020, 08:48:59 AM »
Managed to get the bike running very well.
Being a newbie to BMW k bikes, I was unaware how sensitive that these bikes are to low fuel levels.
Turns out that part of my problem in keeping the bike running was low fuel level. That and a badly split crankcase z hose.

All running fine now.
Just need to check everything else out on the bike and then get the remaining parts on the bike and then it's ready to roll.
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Offline Laitch

  • Faster than a speeding pullet
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Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #23 on: June 26, 2020, 09:38:58 AM »
Turns out that part of my problem in keeping the bike running was low fuel level.
Put your moto's year of manufacture in your profile, too. If yours is a moto with the fuel return outlet attached to the tank's ceiling, there's a modification you can make to keep the level in the tank higher for longer period of time.
  • 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

Offline lawtome

  • Motobrick Curious
  • Posts: 18
Re: New to get back on the road... K75 RT 1995 UK bike
« Reply #24 on: July 07, 2020, 10:30:59 AM »
Thanks Laitch, I've added it now.
I'm struggling to get my head around the VIN for this bike.
In the UK I have to add the VIN to a form to send it to the DVLA and get a registration form from them. (the V5 registration form was lost)

My problem is that my bike appears to have a 12 digit VIN, where a 17 digit code is asked for on the forms.

Any UK riders that have registered their bikes managed to solve this?
  • stockport- England
  • 1994 BMW K75 RT & Yamaha XJR 1300 SP

Tags: ignition switch key