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TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: Nick Kennedy on April 27, 2019, 08:45:53 PM
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Hi Gents
So my super reliable K75RT has a intermittent electrical problem. Bear with me this might be a long post.
A few days back I head out on a ride and the battery light comes on but only half lit. This happens 4 or 5 times in the first 40 miles and then the bike shuts off for a couple of seconds but comes back on. I turn around, stop at a friends house for 45 minutes and ride home no problem.
The next day I put a voltmeter across my battery and go for a 6 mile ride. At first the voltage holds steady at 13.8v but then it starts jumping around, always lower as low as 11.9v I shut the bike off for 20 minutes, start it up and it holds voltage steady at 13.9v
Yesterday I pull the battery which is New, and pull the alternator brushes out, they look good and pull the ground wire and check it and it seems fine. While pulling the ECU plug I notice it was not snapped in tight. I put a voltmeter on the battery and ride 6 miles and It does not flinch, steady at 13.9v. I think it was the ECU plug and I fixed it yahoo.
I change my oils. I start the bike to fill the oil filter in my shop and after 15 seconds it shuts off and the Battery light is half lit. Dammit. After a few seconds like 3-5 the light comes on bright and it starts. Over the next 20 minutes I start the bike several times. Several times when I turn on the key the battery light is only half lit and the motor will not crank, then I wait a few seconds and the battery light comes on bright and it starts right up.
To all you electrical genius's out there please, what is causing this?
I got to get this fixed as the short season is on here
Thanks in advance!
Nick
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Hi Gents
So my super reliable K75RT has a intermittent electrical problem. Bear with me this might be a long post.
A few days back I head out on a ride and the battery light comes on but only half lit. This happens 4 or 5 times in the first 40 miles and then the bike shuts off for a couple of seconds but comes back on. I turn around, stop at a friends house for 45 minutes and ride home no problem.
The next day I put a voltmeter across my battery and go for a 6 mile ride. At first the voltage holds steady at 13.8v but then it starts jumping around, always lower as low as 11.9v I shut the bike off for 20 minutes, start it up and it holds voltage steady at 13.9v
Yesterday I pull the battery which is New, and pull the alternator brushes out, they look good and pull the ground wire and check it and it seems fine. While pulling the ECU plug I notice it was not snapped in tight. I put a voltmeter on the battery and ride 6 miles and It does not flinch, steady at 13.9v. I think it was the ECU plug and I fixed it yahoo.
I change my oils. I start the bike to fill the oil filter in my shop and after 15 seconds it shuts off and the Battery light is half lit. Dammit. After a few seconds like 3-5 the light comes on bright and it starts. Over the next 20 minutes I start the bike several times. Several times when I turn on the key the battery light is only half lit and the motor will not crank, then I wait a few seconds and the battery light comes on bright and it starts right up.
To all you electrical genius's out there please, what is causing this?
I got to get this fixed as the short season is on here
Thanks in advance!
Nick
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Welcome to the site. A lot of good MOE's here!
What's your history with the bike?
Next place to look would be the starter motor brushes.
Try doing a backspin on the starter. With the engine off and in 3th or 4th gear roll the bike backwards down a hill and pop the clutch a few times allowing the starter to spin backwards. This procedure normally dislodges the built up carbon from the brushes allowing the bike to start. The more permanent fix is to remove the starter, pull it apart, check the brushes/commutator and clean.
Starter Motor Backspin (http://"http://www.motobrick.com/index.php?topic=5678.0")
There is also a ground wire underneath the tank.
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+1 on the starter motor. Starter motor cleaning / rebuild tutorial (http://www.k100-forum.com/t2342-starter-motor-cleaning-tutorial)
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If the starter motor brushes don't fix the problem, the next place to service is the ignition switch. The contacts in it get burnt and dirty, and can cause intermittent whack.
http://www.eilenberger.net/K75S/IgnitionSwitch/
Another source of alternator light whack is the heated grip wiring on the throttle grip. The wires can rub through the insulation on the bar end. This problem is unlikely unless you are blowing fuse #1 when things go whack.
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Hey Gents
Update
So I took out my starter motor and cleaned it up. Easy procedure 1 Hr total time.
I think this fixed my problem!! Yahoo
Took it for a ride and voltage held steady at 13.9v, no lights, runs great.
Nothing like the little brick at full throttle pulling past 6 grand. Love it
Thanks for all the advice and postings.
Lets be safe out there this season!
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Gents Same problem continues, Oil pressure and Alt lights come on half lit and bike shuts off. After a few seconds lights come full bright, bike starts and runs great. This is so weird. So I'm going to take the tank off and clean all the grounds and install a new battery to frame ground cable.
Battery is one year old has been on a tender and seems strong.
Any others ideas?
I am very leery of taking the ignition switch and shut off switch apart, I'm afraid to break them but maybe that's in my future?
What do you guys think?
Are those switch rebuilds / cleaning suitable for ham fisted wanna be's??
If I f*%k up those switches then I'm really dead in the water ya know.
The bike has been stored inside its whole life BTW never parked out except on trips.
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This is so weird. So I'm going to take the tank off and clean all the grounds and install a new battery to frame
I am very leery of taking the ignition switch and shut off switch apart, I'm afraid to break them but maybe that's in my future?
Are those switch rebuilds / cleaning suitable for ham fisted wanna be's??
If I f*%k up those switches then I'm really dead in the water ya know.
I think if you keep considering yourself incompetent and ham-fisted, it will be more difficult for you to become competent and adroit. The symptoms aren't weird; they've been described in countless discussions of these motos here regardless of where they have been stored.
Much initiative to do anything is lost in worrying. Do the next task—cleaning the frame grounds and switch connections. The ignition switch has a connector beneath the tank; clean it then spray it with a contact cleaner like DeoxIT to protect it. Spray that on the ground connections, too, after they've been cleaned. Check the battery ground connection on the transmission and the battery connection for tightness. If all that doesn't help, move on to the next task.
Being dead in the water is the risk all of us take by choosing to ride old motos and doing our own work. It's likely most of us have been there at least once, yet here we are. Many of us would rather put ourselves in that state of deadness than pay somebody else to put us there. :giggles
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A side issue. You say you start the bike to fill the oil filter. It's a good idea to fill the oil filter before you install it so the oil pressure builds up much quicker.
(and a light smear of oil on the O ring)
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It's a good idea to fill the oil filter before you install it so the oil pressure builds up much quicker.
I've never done that because I've no desire to make a simple procedure more complicated in any degree. How much quicker is much quicker? :giggles If an engine is warm when the oil is changed, there will be enough residual oil on parts to provide sufficient lubrication until full circulation occurs when enough oil has been put in the crankcase.
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True, I should have just said quicker. I spose it would be a tiny amount of time.
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Laitch,
If I could say it better I would!
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The difference in getting full oil pressure is about 50-70 revolutions of the crankshaft, tops. No big deal for the residual oil in the bearings.
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I thought I had a electrical problem
are you guys mixing up your meds?
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I thought I had a electrical problem
are you guys mixing up your meds?
Have you mastered your anxiety and cleaned the grounds as was suggested? We've been in an intervention with somebody else. :giggles
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FWIW it was a personal intervention :eek2:
Seriously though, the man who could/would know/help has passed and the other is most likely busy or on another forum. You are left with a healthy dose of realism, abstract musing, and hard knocks. My experience tells me to follow Laitch's advice and methodically clean electrical connections. First and foremost being system grounds (including the starter) and primary voltage supply--which it sounds like you have started doing...continue.
When you say the some lights are dim, did you also check the horn and headlights? I personally have upgraded my primary supply and ground cables from EME. Not sure it helped the bike, but I do feel better. While very rare, alternators can fail intermittently. I would consider this as a last resort. It was mentioned in different posts that there can be a wire failure near the head-stock due to wire age and motion/friction.
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Well, back to the problem with the half-lit charging light. Since you checked the alternator and starter motor brushes, there could be issues with the load shed relay. Have you tried swapping that relay with the horn relay to see if there is any improvement?
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Nick,
Try swapping relays as Rob suggest. But my money is on the starter, maybe someone local has a spare?
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Nick,
I am on my way to Colorado and planning on riding 550. If you want you could try my starter, shoot me a PM.
Also there is a good guy/shop not far from you Basin motorcycle works in Mancos Co. I hope Harry is still at it, look him up.
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Nick,
I forgot to say I'm I Price Ut for the night heading for Co National Monument tomorrow.
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. . . I'm I Price Ut for the night . . .
CODE-TALKER ALERT. :tinhat2
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If the starter brushes are too short the problem could continue. Did you measure the length of the brushes when you cleaned them?
Regards Martin.
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This is only a suggestion. If your lucky, wiggling (or replacing) the battery negative will affect the light, pointing to an easy fix.
Or wiggle the positive or the EFI connector (or clean) Or check connections for voltage drop. They are only suggestions, no big deal.
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So the saga continues
I start the bike it runs for maybe 30 secs- minute, shuts off with ign oil pressure lights half lit. Turn off key turn on key starts up- runs all day.
I know if got to take apart and clean the ign switch, hasn't stranded me yet. If I break the plastic tabs on that switch I'm screwed.
Another problem is my starter for some reason has stuck on 3x recently. yesterday I could not find a allen wrench and it turned for over a minute. Starter got warm not hot. Battery is new and strong.
So I want to replace my starter relay, euromotoelectric wants $50 for one
Question; can I pry to top off my relay and clean the contacts myself?
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I start the bike it runs for maybe 30 secs- minute, shuts off with ign oil pressure lights half lit. Turn off key turn on key starts up- runs all day.
So I want to replace my starter relay, euromotoelectric wants $50 for one . . . Question; can I pry to top off my relay and clean the contacts myself?
About the stalling: remove the fuel cap assembly and determine if your fuel pump is loose in its holder. If it bottoms out on the floor of the tank, intermittent stalling as you have described will follow. Have you checked that the battery connections are tight and the batter ground strap on the transmission is tight?
Did you swap relays as was suggested in Reply #16?
If you believe the starter relay is faulty and needs to be replaced but you don't have the funds to replace it what do you lose by trying to clean its contacts yourself? When a relay is thought to be faulty, the first line of diagnosis is use of a multimeter to check the relay and connections; the second line of diagnosis is to knock it a few times with a screwdriver handle then see if it comes to life. :giggles The next is to swap in a working relay of the same type from a different system on the moto—that has already been suggested here. After that, there's disassembly as you're contemplating. Finally, there's replacement. If you have determined that a relay is faulty, find the model number of the relay and go Web-shopping for a cheaper price.
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Shot in the dark - could it be the the pump isnt' building enough pressure so it is burning what is in the line but it isn't enough to really run. When it shuts down, there is some pump run-on and now the pressure is there. Could it be the fuel pressure regulator?
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If the idle speed is low it can effect the lights. If you start it on a cold morning with no choke the idle speed might be that low that a stall results with the lights glowing. The second attempt would be better especially if helped with a twist on the throttle. You might have a semi cruise control type bolt under the twist grip adjusted so that it doesn't fully retract straight away resulting in a higher idle speed on the second attempt. Hopefully that might be the case, then there is nothing wrong with your bike, apart from the relay, but I'm guessing it's got high mileage and the bearings have done a lot of work.
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Gents
So I bucked up and cleaned my Ign switch last night. Was fairly difficult [ for me anyway ] to reassemble it. But I figured it out and it worked.
Anyway this may have fixed my problem. I hope so. I started it up and it did not shut off for the first time in 3 months.
Thanks to all who have responded, this forum is a great resource!
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So I bucked up and cleaned my Ign switch last night.
:clap:
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So the saga continues
I start the bike it runs for maybe 30 secs- minute, shuts off with ign oil pressure lights half lit. Turn off key turn on key starts up- runs all day.
Another problem is my starter for some reason has stuck on 3x recently. yesterday I could not find a allen wrench and it turned for over a minute. Starter got warm not hot. Battery is new and strong.
Before I spent any money on a starter relay I would spend an afternoon cleaning the contacts and the connector under the tank for the starter/kill switch on the right handlebar. Both of the problems you mention could be attributed to or aggravated that switch.
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Gents
So I bucked up and cleaned my Ign switch last night. Was fairly difficult [ for me anyway ] to reassemble it. But I figured it out and it worked.
Anyway this may have fixed my problem. I hope so. I started it up and it did not shut off for the first time in 3 months.
Thanks to all who have responded, this forum is a great resource!
That switch is a common source for whack on these old girls. It's good you finally got into it.
I would still take the time to shoot some Deoxit into the Start/Kill switch which may be the source of your starter run-on problem.