Author Topic: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)  (Read 89948 times)

Offline volador

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #500 on: May 14, 2020, 06:17:49 PM »
'Pin #85 of FI relay should see -12v: It reads nothing. However when red lead is on battery positive and black to pin #85 it reads 12v when the start button is depressed.'

'correct ground test' is verified- you have established ICU Pin7 is providing ground for Pin85 when starter button is depressed

Pin #30 of FI relay should see +12v at any time even with ignition off: It reads nothing.

you need to check wire to FI relay Pin30 as you said should see +12V  -maybe sparky sparky no likey

you can jumper Starter relay Pin30  to FI relay Pin30 for +12V for test starting
  • NYC NY
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Offline DJEwen

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #501 on: May 31, 2020, 06:17:41 AM »
'Pin #85 of FI relay should see -12v: It reads nothing. However when red lead is on battery positive and black to pin #85 it reads 12v when the start button is depressed.'

'correct ground test' is verified- you have established ICU Pin7 is providing ground for Pin85 when starter button is depressed

Pin #30 of FI relay should see +12v at any time even with ignition off: It reads nothing.

you need to check wire to FI relay Pin30 as you said should see +12V  -maybe sparky sparky no likey

you can jumper Starter relay Pin30  to FI relay Pin30 for +12V for test starting

Ok- I checked the connections in the fuel injection relay socket and all seems well, no issues. The replacement relay arrived and I installed it but I still have no fuel pump. Itís also fantastic weather outside :(
  • Scotland
  • 1985 K100 'Revive', 1987 K100 LT

Offline Laitch

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #502 on: May 31, 2020, 08:09:26 AM »
Have you removed the fuel pump and checked it for operation on the bench. The battery problem and the fuel pump problem could be coincidental.
  • Along the Ridley in Vermont.
  • 1995 K75 80,000 miles
I wept because I had no radials until I met a man who had no splines.
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Offline DJEwen

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #503 on: May 31, 2020, 08:46:58 AM »
Have you removed the fuel pump and checked it for operation on the bench. The battery problem and the fuel pump problem could be coincidental.

I have, Laitch. Itís working fine.

Iíve had some mice recently, caught a load. Iím wondering if maybe something has been chewed.
  • Scotland
  • 1985 K100 'Revive', 1987 K100 LT

Offline Laitch

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #504 on: May 31, 2020, 08:51:55 AM »
Is there continuity at your recently cleaned four-pin plug and at the connection between the fuel gauge and the pump?
  • Along the Ridley in Vermont.
  • 1995 K75 80,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline DJEwen

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #505 on: June 01, 2020, 08:43:00 AM »
Is there continuity at your recently cleaned four-pin plug and at the connection between the fuel gauge and the pump?

There is continuity at the four pin. Are you suggesting testing for continuity inside the tank from the 4 pin to the pump? I hadn't done that.
I remember back at Post #239 on page 10 then RBMs reply at #242 he suggests dodgy internals of the old type senders but he may be referring to the thermistors to the fuel level gauge.
  • Scotland
  • 1985 K100 'Revive', 1987 K100 LT

Offline Laitch

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #506 on: June 01, 2020, 11:32:34 AM »
There is continuity at the four pin. Are you suggesting testing for continuity inside the tank from the 4 pin to the pump?
That's what I'm suggesting.  icon_cheers
  • Along the Ridley in Vermont.
  • 1995 K75 80,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline DJEwen

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #507 on: July 25, 2020, 02:26:08 PM »
Iíve still not got the K started, neither have I got the garage built. To satisfy my throttle therapy in the meantime, I picked up a used 2018 R NineT Pure Sport with 1300miles on the clock. Itís an effortless machine to ride.

  • Scotland
  • 1985 K100 'Revive', 1987 K100 LT

Offline Laitch

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #508 on: July 25, 2020, 09:46:09 PM »
I picked up a used 2018 R NineT Pure Sport with 1300miles on the clock. Itís an effortless machine to ride.
That looks fun! Does Pure Sport translate from German as Send your luggage ahead:laughing4-giggles:
  • Along the Ridley in Vermont.
  • 1995 K75 80,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline Martin

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #509 on: July 26, 2020, 12:59:23 AM »
No Laitch it translates to I wish I had a padded seat or a more ample bum. One of the OZ Kluster Krew has one.
Regards Martin.
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Offline DJEwen

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #510 on: July 26, 2020, 05:16:21 AM »
That looks fun! Does Pure Sport translate from German as Send your luggage ahead:laughing4-giggles:

Meh, I managed with the K!

No Laitch it translates to I wish I had a padded seat or a more ample bum. One of the OZ Kluster Krew has one.
Regards Martin.


Luckily, it has the upgraded seat, and twin gauges from the racer so I have GPI, rev counter fuel gauge :D
  • Scotland
  • 1985 K100 'Revive', 1987 K100 LT

Offline Laitch

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #511 on: July 26, 2020, 09:25:06 AM »
It's an attractive design. I found a tutor if you want to test its limits. I'd give it a try if one came my way.  112350
  • Along the Ridley in Vermont.
  • 1995 K75 80,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline emdy

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #512 on: August 24, 2020, 10:08:24 AM »
Curious if the fuel pump issue was resolved. I'm in a similar situation. I started a scrambler conversion of an 85RS last winter (not as nice as yours). Installed a BEP, did the mod on the flasher for LEDs. Then I got sidetracked by life and pandemics and whatnot.

Now I'm back and trying to get started and everything is cranking over, but no fuel delivery, no power to fuel pump, no power to gas tank connector, no power to fuse 6,  no 12v to pin 85 on fuel pump relay when the starter is pressed.

I tried hotwiring the fuel pump from the fuse box and it whirs right up, so I don't think there is a problem with the pump, or connection from the relay. But I'm sort of stuck on what to check next. I'm sure I messed something up when I was in there last winter.
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Offline DJEwen

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #513 on: August 24, 2020, 11:06:50 AM »
Curious if the fuel pump issue was resolved. I'm in a similar situation. I started a scrambler conversion of an 85RS last winter (not as nice as yours). Installed a BEP, did the mod on the flasher for LEDs. Then I got sidetracked by life and pandemics and whatnot.

Now I'm back and trying to get started and everything is cranking over, but no fuel delivery, no power to fuel pump, no power to gas tank connector, no power to fuse 6,  no 12v to pin 85 on fuel pump relay when the starter is pressed.

I tried hotwiring the fuel pump from the fuse box and it whirs right up, so I don't think there is a problem with the pump, or connection from the relay. But I'm sort of stuck on what to check next. I'm sure I messed something up when I was in there last winter.

Hi Emdy, Iíve not actually gotten any further with the fault finding. Iím not fully set up at my new place yet and home renovations are at the front of the list so canít help you out. Could be a good year or so before I get to it, I just bought another bike to get me through in the mean time.

Good luck.
  • Scotland
  • 1985 K100 'Revive', 1987 K100 LT

Offline DJEwen

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #514 on: February 11, 2021, 06:40:28 PM »
A while since Iíve been in here. Hope everyone is doing the best they can in these horrid times.

I still havenít got a garage at my new house but the K will be moving inside shortly. Iím looking at potentially adding a Motogadget m-unit to move away from problematic/aged relays etc in the hope to fault find the no start issue and also massively reduce the possible no start scenarios.

  • Scotland
  • 1985 K100 'Revive', 1987 K100 LT

Offline Laitch

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #515 on: February 11, 2021, 11:28:52 PM »
Thanks for the update! Glad you still have that critter.  112350
  • Along the Ridley in Vermont.
  • 1995 K75 80,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline daveson

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #516 on: February 12, 2021, 02:53:30 PM »
Hi DJ,

I've read the last two pages to try and get a grasp of the no start problem.

I think you say there is no power to pin 30 of the fuel injection relay, but I don't think it's been addressed. I'd run a temporary wire to it.

Next, as others mentioned, I'd test the hall sensors. I'd use a 12Volt, LED test light. You can probably get one cheap at your local hardware (been wondering a bit about brexit affect on imports) It's a simple easy check. I'll attach photos and a bit, later.

Next I'd check the ICU, using Bert's guide. If all the inputs to the ICU are good, but not the outputs, you probably need to replace it.
  • Victoria, Australia
  • Current;'85 K100RT~100,000km; four other bricks. Past; 1500 Vulcan, V Star 650, KLX 250(dirt bike) TT250(dirt bike)

Offline daveson

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #517 on: February 12, 2021, 08:42:58 PM »
Hall sensor test:

With the negative battery lead to top left pin, positive to top right, test light clamp on battery positive and probe to lower left pin, the test light should go on. (photo 1)


With probe to lower right pin, the light should go on. (photo 2)


Repeating these tests with the sensors blocked, the light should remain off. (photo 3)


With a bit of effort, these tests could be done without removing the hall sensors.


  • Victoria, Australia
  • Current;'85 K100RT~100,000km; four other bricks. Past; 1500 Vulcan, V Star 650, KLX 250(dirt bike) TT250(dirt bike)

Offline daveson

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Re: "Revive" (1985 K100 Street Scrambler Build, not a Cafe Racer)
« Reply #518 on: February 19, 2021, 08:07:11 PM »
Question;

Do you have three red wires to battery positive or two? You should have three.

Since you installed the new battery, the bike has not started, and nor have you had power to pin 30 of the fuel relay.

There should be three red wires to battery positive, one to the alternator, one to the fuel relay and one to the starter relay. Some bricks have both relay wires connected with one connector, on some bricks they're separate, so then it would be three wires with three connections. Sometimes they're not bound together, in which case it would be easy to overlook the wire to the fuel relay, it might have fallen in an inconspicuous place.

Hopefully it's that simple.
  • Victoria, Australia
  • Current;'85 K100RT~100,000km; four other bricks. Past; 1500 Vulcan, V Star 650, KLX 250(dirt bike) TT250(dirt bike)