Author Topic: Riding fine, then bike died  (Read 5637 times)

Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #25 on: August 12, 2023, 12:14:18 PM »
Hahaha! My bad - frustration must jumble up text.

No power to the tabs in the tank. So the float must be at fault, eh? The pump is fine, tested it on a battery charger and it works.
  • Bordentown NJ
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #26 on: August 12, 2023, 12:23:27 PM »
Un-jumble and answer all of the questions.  :laughing4-giggles:
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Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #27 on: August 12, 2023, 01:36:53 PM »
Under cranking the connector is getting the proper voltage. The connectors in the gas tank aren’t getting any power according to my voltmeter, so I’d assume from that there’s no power making it into the tann
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #28 on: August 12, 2023, 03:42:23 PM »
From your description, the fuel injection relay seems to be working okay.

The wire getting the correct voltage on the down stream side of the connector when cranking should find its mate on the downstream site of the fuel level sender. Maybe you've got your wires crossed at the fuel level sender, 4-pin connectors and/or the pump terminals. Revisit all connections; establish continuity with the wire that allegedly powers up when cranking.

I'm returning to a broken alternator clutch and cleaning up the monkey nut shards and clutch vane fragments left by its failure.

Replacement parts standing by; photos to be posted in a new thread someday.  :laughing4-giggles: 
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Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #29 on: August 12, 2023, 04:36:02 PM »
From your description, the fuel injection relay seems to be working okay.

The wire getting the correct voltage on the down stream side of the connector when cranking should find its mate on the downstream site of the fuel level sender. Maybe you've got your wires crossed at the fuel level sender, 4-pin connectors and/or the pump terminals. Revisit all connections; establish continuity with the wire that allegedly powers up when cranking.

I'm returning to a broken alternator clutch and cleaning up the monkey nut shards and clutch vane fragments left by its failure.

Replacement parts standing by; photos to be posted in a new thread someday.  :laughing4-giggles:

Wires are on the correct terminals and all. No dice :( Double checked my new connections - all are twisted together and soldered nice and tight. No problems there.

Good luck with the new parts, hopefully the day comes where I can help you :laughing4-giggles:
  • Bordentown NJ
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #30 on: August 12, 2023, 07:40:55 PM »
. . . hopefully the day comes where I can help you :laughing4-giggles:
I still have three cords of wood to move and stack, so if you're in the neighborhood, drop in.
If everything you indicate about your connections is accurate, it seems to me that the wire to the pump that passes through the fuel level sender has been broken. It's also possible some of the crew here will come up with more accurate observations than mine that will sort out this problem.
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Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #31 on: August 16, 2023, 09:26:40 AM »
Alright everyone - update. Tested with positaps and bypassed the connector. It's definitely the fuel float. Any ideas on how to inspect it or bypass it without getting a new one? I just bought it from K Bike Parts Holland not 2 months ago, so it's a little frustrating (but what can you do when it comes to used parts).
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #32 on: August 16, 2023, 09:59:28 AM »
Thanks for the update.

For clarity, refer to the source of the problem as the fuel level sender wiring, not the fuel float. Beemuker, a member here, is having a similar challenge; in these aging parts, it is becoming more common especially if corrosion from old fuel has been allowed to occur within the tank. He's attempting to replace a faulty sender with an ebay replacement. He's following successful technique done by this rider. By all appearances, this solution will allow you to remove the OEM sender, analyze how it's wired and maybe even repair it eventually if a working OEM doesn't fall into your lap. In the meantime, you'll be able to ride.  icon_cheers   


When I first got my Brick, I carried a spare gallon of fuel with me, filled the tank then allowed my Brick's engine to start missing from lack of fuel. Using the tripmeter, I derived an average over four trips of mixed terrain riding. 224 miles is the point at which the engine becomes fuel starved on hills, so I always refuel at 210 miles or less. My fuel light registers at 170 but I ignore it unless there's a long stretch ahead without refill. That's one source of excitement in my life.  177381 The odometer/tripmeter method works well; all that is needed is awareness. Awareness is a major component of safe riding anyway.

Fix it the simple way being offered at the link I provided to avoid chronic sender envy. :laughing4-giggles:
  • Along the Ridley in Vermont.
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Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #33 on: August 16, 2023, 10:27:27 AM »
Thanks for the update.

For clarity, refer to the source of the problem as the fuel level sender wiring, not the fuel float. Beemuker, a member here, is having a similar challenge; in these aging parts, it is becoming more common especially if corrosion from old fuel has been allowed to occur within the tank. He's attempting to replace a faulty sender with an ebay replacement. He's following successful technique done by this rider. By all appearances, this solution will allow you to remove the OEM sender, analyze how it's wired and maybe even repair it eventually if a working OEM doesn't fall into your lap. In the meantime, you'll be able to ride.  icon_cheers   


When I first got my Brick, I carried a spare gallon of fuel with me, filled the tank then allowed my Brick's engine to start missing from lack of fuel. Using the tripmeter, I derived an average over four trips of mixed terrain riding. 224 miles is the point at which the engine becomes fuel starved on hills, so I always refuel at 210 miles or less. My fuel light registers at 170 but I ignore it unless there's a long stretch ahead without refill. That's one source of excitement in my life.  177381 The odometer/tripmeter method works well; all that is needed is awareness. Awareness is a major component of safe riding anyway.

Fix it the simple way being offered at the link I provided to avoid chronic sender envy. :laughing4-giggles:

Hey Laitch, will do.

The method you linked was basically what I had to do when I bought my brick. The fuel sender unit was deleted and the bike was a no-starter because of faulty connections. I resoldered right to the plate connections and it fired up, but I wanted to replace with a proper unit. I'm going to try this out yet again (but the right way) and see what happens. I also might just reattach that plate since I saved it, we'll see!

Also, my odometer doesn't work either - I'm really going to have to get good at distance estimation  :laughing4-giggles:
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #34 on: August 16, 2023, 11:03:29 AM »
Also, my odometer doesn't work either - I'm really going to have to get good at distance estimation  :laughing4-giggles:
More often than not that can be fixed by gear replacement. There are several threads here and elsewhere about that task. You can try that during your idle hours whenever they might be. It's in Spanish but if you click on the CC icon, you can set subtitles in American-English and get some training.


If you inspect the gears, it's possible you'll discover broken or missing teeth among them. Gears are available. Some members have found replacements among bulk packs found at hobby stores but specialists in odometer repairs also sell them if you can supply number of teeth, diameter and thickness measurements of the gears. If all gears are okay and firmly attached to their shafts then its an electrical problem. frankenduck has helpful concerning the instrument cluster and odometer at his site.

As usual, patience and photographing components before disassembly can lessen frustration during reassembly.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #35 on: August 16, 2023, 01:40:53 PM »
Thanks for the info on the odo. That's next.

Just soldered wires to the plate w/o the fuel sender unit on it, and it's drawing constant power. Hooked it up to the pump and voila, we have power to the pump. I'm draining the gas tank now and am going to swap out the sender unit mounts and see what happens.

We're getting close y'all!
  • Bordentown NJ
  • 1993 BMW K75S

Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #36 on: August 16, 2023, 02:33:31 PM »
Aaaaaand she's a runner, folks. Thanks everyone for the help - used the solve just sent by Laitch to bypass the fuel sender unit. Luckily, I had a spare plate lying around with the sender broken off, and soldered directly to that.

Appreciate all of the assistance!
  • Bordentown NJ
  • 1993 BMW K75S

Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #37 on: August 16, 2023, 04:07:19 PM »
Aaaaaaaand I spoke too soon. I was going on a test ride around my neighborhood and down the street when I got an insane squeak/squeal and knock out of the engine. I wasn't pushing it mighty hard, staying within reasonable RPMs and speed, but I did go 55mph on a flat out road adjacent to the neighborhood.

Anyway, seems that the bike intermittently cuts in and out: https://youtube.com/shorts/uRgVDm9Q7Ps?feature=share

Any ideas or familiarity?
  • Bordentown NJ
  • 1993 BMW K75S

Offline Laitch

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Re: Riding fine, then bike died
« Reply #38 on: August 16, 2023, 07:31:40 PM »
Just soldered wires to the plate w/o the fuel sender unit on it, and it's drawing constant power. Hooked it up to the pump and voila,
When is it drawing "constant power?" It should have power only when the starter is cranking the engine or the engine is running. It should not have power when the key is turned to On and nothing else is happening.

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Offline The Mighty Gryphon

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Re: Riding fine, then bike died
« Reply #39 on: August 16, 2023, 08:01:00 PM »
THe first thing I would do is get into the engine and check the cam timing. 

Also, are you sure you have the fuel pump wires to the correct wires in the harness?  Laitch is right that it should only run when the engine is cranking or running.
  • In my garage in Marilla, NY
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'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #40 on: August 16, 2023, 08:13:31 PM »
Constant power during riding - not when key is turned and bike isn’t on. Everything is good in the wiring.

I have the clymer, so I’ll have to bust into that to see how to check  the timing. What exactly am I looking for? I found another forum post that it could be a water pump, but I don’t know much about anything when it comes to these things.
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Offline The Mighty Gryphon

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Re: Riding fine, then bike died
« Reply #41 on: August 16, 2023, 08:58:08 PM »
Cam timing is what you are looking for.  There are arrows on the cam sprockets that need to align with each other at top dead center of cylinder #1 or something like that.  The shop manual will tell you what to do. It's probably okay, but you don't want to take a chance that it is off.
  • 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 rocketbrick

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Re: Riding fine, then bike died
« Reply #42 on: August 16, 2023, 09:11:20 PM »
Will do!

I'm really concerned about that squealing. It sounds expensive and time-consuming, so I'm hoping I don't have to drop the whole engine. I know you can take the timing cover off with the engine still on the bike, I have just never messed with timing in anything before. Wish me luck!
  • Bordentown NJ
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #43 on: August 16, 2023, 10:04:29 PM »
Don't worry. Be happy! One thing at a time. If it ran well once, it can run well again, probably.  :laughing4-giggles:
  • Along the Ridley in Vermont.
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #44 on: August 16, 2023, 11:24:46 PM »
Just soldered wires to the plate w/o the fuel sender unit on it, and it's drawing constant power. Hooked it up to the pump and voila,  we have power to the pump.
Constant power during riding - not when key is turned and bike isn’t on. Everything is good in the wiring.
Here's what's confusing me, rocket. You indicate that you soldered wires to the plate and had constant power. You hadn't connected to the pump yet so you weren't riding and the engine wouldn't have been running. Then, you seemed to hook up the pump and voila it worked. Constant power shouldn't have been at the wire unless the starter or engine were running. All I'm trying to understand is whether you've connected the correct wires to supply the pump with full voltage. I hate to be a Doubting Thomas concerning how you've wired stuff, so I'll be a Doubting Laitch.

I found another forum post that it could be a water pump, but I don’t know much about anything when it comes to these things.
You're gonna learn, rocket.  :laughing1: Start your engine, get a screwdriver, put its handle next to your ear canal opening, place its blade or point against the water pump cover. You'll hear if the sound is coming from there. Put it up against the timing chain cover, and any other place to locate the sound. My recent favorite place to listen was an alternator.  :laughing4-giggles:

 Your video recording technique for capturing symptoms is useful and an example for others here to follow.
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Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #45 on: August 17, 2023, 07:09:41 AM »
Here's what's confusing me, rocket. You indicate that you soldered wires to the plate and had constant power. You hadn't connected to the pump yet so you weren't riding and the engine wouldn't have been running. Then, you seemed to hook up the pump and voila it worked. Constant power shouldn't have been at the wire unless the starter or engine were running. All I'm trying to understand is whether you've connected the correct wires to supply the pump with full voltage. I hate to be a Doubting Thomas concerning how you've wired stuff, so I'll be a Doubting Laitch.
 You're gonna learn, rocket.  :laughing1: Start your engine, get a screwdriver, put its handle next to your ear canal opening, place its blade or point against the water pump cover. You'll hear if the sound is coming from there. Put it up against the timing chain cover, and any other place to locate the sound. My recent favorite place to listen was an alternator.  :laughing4-giggles:

 Your video recording technique for capturing symptoms is useful and an example for others here to follow.

I totally understand you being a doubting Laitch, no argument from me - I just phrased that incorrectly. I’m the pump runs when the bike is running, it’s off when the bike is off (that includes when the key is in the on position and the bike is I started). Pump seems to be getting full power on my test ride and making that classic, sweet whine.

And the old fashioned mechanic stethoscope technique! I completely forgot about that. I’ll definitely be giving that a shot. The timing cover and pump cover are pretty close together, so at least I won’t need to go far  :laughing4-giggles:
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Offline Laitch

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Re: Riding fine, then bike died
« Reply #46 on: August 17, 2023, 07:56:20 AM »
The timing cover and pump cover are pretty close together, so at least I won’t need to go far  :laughing4-giggles:
It's hot out there! I glad you're seeking opportunities to conserve your energy. Be sure to listen to the alternator, too—just for practice.
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Offline rocketbrick

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Re: Riding fine, then bike died
« Reply #47 on: August 17, 2023, 08:30:55 AM »
Haha! Conserving energy is what I'm all about. I will definitely.

Also, an important symptom I just remembered and left out (only because I'd never seen the light before and the icon had worn off). The oil pressure light was turning on while I was riding, which is when I promptly returned home. Any light isn't a pleasant one, right?

I'm not sure if that narrows it down to the oil pump or not, but I'm brainstorming until I can work on it this weekend.
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Offline The Mighty Gryphon

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Re: Riding fine, then bike died
« Reply #48 on: August 17, 2023, 09:32:19 AM »
The light means you are losing/lost oil pressure.

The fact you lost oil pressure could be either the cause of the noise or a result of it.  I would avoid running the engine until I could identify the source of the noise and the oil idiot light. 

First place to look would be the oil pump on the front of the engine.

You also need to check the oil filter.  It may either be loose and leaking or plugged and not flowing oil.  When was the last oil and filter change?
  • 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 frankenduck

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Re: Riding fine, then bike died
« Reply #49 on: August 17, 2023, 09:43:52 AM »
The oil pressure switch grounds to illuminate the light.

Assuming that you have adequate oil in the motor, other possible causes of that light coming on are:

1 - The wire insulation is worn and grounding somewhere.

2 - The oil pressure switch has failed.
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