Engine Cuts Out!

Discussion in 'Airheads' started by GoBrave, Jul 9, 2020.

  1. GoBrave

    GoBrave Been here awhile

    Joined:
    Apr 4, 2017
    Oddometer:
    152
    Location:
    Ontario Canada
    My /7 will misfire or hiccup every once in a while. Very slight and almost unnoticeable. But! In the last few weeks it's gotten worse. I am watching the tach and the bike misses and the tach jumps so I know I'm not imagining it! At first I thought it corresponded to hitting bumps in the road and maybe I was letting up on the throttle or some thing.
    So it runs fine for 15 minutes and then it starts to act up. Getting worse each time. After another 10 minutes it was backfiring and was thinking I wasn't going to make it home.
    It seems like both cylinders are quitting at the same time. I put a Red Center Ignition System on last year. One thing I'm going to check is that the pick up didn't come loose. Already looked at the plugs and they seem fine. Nice dry dark grey.

    So how the heck am I going to trouble shoot this one?

    Thanks
    GoBrave
    #1
  2. oldgsbob

    oldgsbob Adventurer Supporter

    Joined:
    Jul 20, 2011
    Oddometer:
    90
    Location:
    Surrey, England
    it sounds like the hall effect sensor in the bean can, if you have that type. It gets warm then starts playing up before complete failure.
    #2
  3. Warin

    Warin Retired

    Joined:
    Aug 30, 2012
    Oddometer:
    10,825
    Remove the front engine cover and leave it off until you find the problem.

    When it acts up, throw water on to an ignition system component. This cools the component. If the fault goes away then it is probably the component you just cooled. Repeat for each component until you find the suspect.

    Why water? Cheap, you probably already have it and it has a large thermal mass. You can use other things .. $$. Note: electronic components are sealed against water, teh sealing may not work against other things.
    #3
  4. GoBrave

    GoBrave Been here awhile

    Joined:
    Apr 4, 2017
    Oddometer:
    152
    Location:
    Ontario Canada
    I don't have the bean can anymore. I have a Red Center for about a year now I think. The advance system was shot on the bean can so it was time for the upgrade.
    I think this problem has been around for a while but to a much lesser almost unnoticeable extent.

    I will read up on how to test the coils. I don't think its a carb problem just because it is both cylinders. Or at least seems like both.

    Any recommendations for which Dynatek coils I should be looking for? That pair up with the Red Center Ignition.

    GoBrave
    #4
  5. Beemerguru

    Beemerguru Beemerguru...G/S guy

    Joined:
    Nov 7, 2006
    Oddometer:
    1,920
    Location:
    Redwood City, CA
    Call the people at EME..they'll match you up with the right coils and parts.
    #5
  6. kcoralj

    kcoralj Been here awhile

    Joined:
    Jun 5, 2016
    Oddometer:
    330
    Location:
    Wisconsin
    That tach jump, I don't think a coil would produce that. I'd think it would be that hall sensor or the advance unit, I don't know much about the red center though.
    Maybe the hall sensor got contaminated with some metal chips? I know from working on my bean can that they like to pick up any iron in the vicinity, which is a pain as I'm a machinist.
    #6
  7. GoBrave

    GoBrave Been here awhile

    Joined:
    Apr 4, 2017
    Oddometer:
    152
    Location:
    Ontario Canada
    Hi kcoralj. The tach doesn't jump....my bad. It drops. Just a little, maybe 100 rpm and other times 2000 rpm! Engine backfires too. Im pulling the cover off the front to see if anything looks loose in the morning.
    #7
  8. Plaka

    Plaka Brevis illi vita est

    Joined:
    Jun 19, 2010
    Oddometer:
    6,721
    Location:
    .
    My Understanding is that the Red Center ignition is an Australian product. Is it really what you have? The Alpha Ignition has a big red label covering the front of the 'beancan" and people mistakenly call them Red Center ignitions.

    Do you have a stock or replacement ICU? Is it on a heat sink? When was the last time you replaced the thermal paste under it. I would start there.

    Electronic faults are commonly thermal and can be found by cooling. The component fails when it gets too hot. I never use water, it is conductive and corrosive. Don't get anything wet that does not regularly get wet in the course of riding. I look for thermal faults with regular electronic chiller spray made for the purpose. It is unlikely to work for a hall sensor because the thing is buried in its can and you cannot get to it. But the HAll sensor does have a transistor in it so that is a point of failure....but it a long shot. If I were searching for thermal faults I would start with the ICU. Try idling in the driveway with a fuel bottle hooked up and hit the ICU with a hair dryer (or even a heatgun some distance away on low) and see if you can reproduce the problem on the centerstand.

    try heating the coil too.
    #8
  9. kcoralj

    kcoralj Been here awhile

    Joined:
    Jun 5, 2016
    Oddometer:
    330
    Location:
    Wisconsin
    Oh a drop is what I meant, mine dropped to zero (or close) and then snapped back sometimes with a backfire through the exhaust when my stock hall sensor was getting old. Obviously due to the lack of a trigger signal, I took that as a warning to replace the sensor before I got stranded.
    #9
  10. boxerboy81

    boxerboy81 Stay Horizontal

    Joined:
    Jul 22, 2009
    Oddometer:
    3,995
    Location:
    Melbourne, Oz
    Find Prutsers thread and read up... here it is. https://advrider.com/f/threads/new-part-from-bmw.1241937/page-9.

    Is your tacho acting the same now? When it happens, how long does it take to recover?
    I'm thinking that if it was electrical then the tach would go back to zero? I'm wondering if a small drop relates more to transiently less fuel?
    Next time it happens I'd be inclined to turn the taps off immediately and inspect the bowls for volume. Also, check your floats turn the flow off at the appropriate level.

    I'm thinking along the lines of fuel tap blockages or fuel filter blockages? Anyhow, it's easy to assess. Have you checked the fuel flow rate? It should flow easily.The taps have inline filters that might clog up, causing reduced flow.

    The other easy things to eliminate before getting concerned about expensive stuff includes the battery cable. Is it tight? Can you see green under it? Might it be broken?
    Are the earth connections intact, eg at the trans and at the L coil mount? The coil mount isn't particularly strong and it can crack. That can create a problem for earth.
    Are the coil connections clean? They can go green where the HT leads connects to the coil.
    Check the ICU paste. When was that last changed?

    The red centre can is likely from the same factory in Taiwan that the Alpha can is from...Emerald Isle. I can't be certain, but I seem to recall the very early ones had an issue. I've had two Red Centre ones and they've been excellent.
    #10
  11. Beemeup

    Beemeup 1978 R100/7

    Joined:
    Sep 1, 2014
    Oddometer:
    1,364
    Location:
    Washington State
    Don't overlook the simple. Mine did that on the freeway, I stopped and swapped the electronic ignition for the old points. Turns out in doing so that I had a loose connection on a coil.
    #11
  12. GoBrave

    GoBrave Been here awhile

    Joined:
    Apr 4, 2017
    Oddometer:
    152
    Location:
    Ontario Canada
    Yes it is a Red Centre. I put it in last year. The module is mounted on an aluminum bracket with grease.

    I will look for a loose wire. All along I was thinking that’s the problem. Also the way the battery is mounted isn’t just right. The hold down is stupid close to the top mount terminals. It’s over 4 years old. “Seems” to work ok. Could the battery be shorting out?
    #12
  13. Beemeup

    Beemeup 1978 R100/7

    Joined:
    Sep 1, 2014
    Oddometer:
    1,364
    Location:
    Washington State
    Sounds like the battery isn't right for the bike and needs to be really secure. Shorting to the frame would create big sparkles!
    #13
  14. GoBrave

    GoBrave Been here awhile

    Joined:
    Apr 4, 2017
    Oddometer:
    152
    Location:
    Ontario Canada
    A battery can short internally also.
    #14
  15. Box'a'bits

    Box'a'bits In need of repair Supporter

    Joined:
    Sep 26, 2008
    Oddometer:
    4,437
    Location:
    Wellington, New Zealand
    One other thing to check is dirty internals on your kill switch. I have just cleaned mine to resolve a similar issue.
    #15
  16. Beemerguru

    Beemerguru Beemerguru...G/S guy

    Joined:
    Nov 7, 2006
    Oddometer:
    1,920
    Location:
    Redwood City, CA
    Get a timing light and connect it to each cylinder for a couple minutes while you start the engine and run it up and down a couple times..hopefully you'll see a constant flicker on each side. If not, check the spark pug wires and coil connections. You should also take the coil off - 2 allens accessed from the left side if still stock - and see if there's a crack anywhere on the coil surface. A crack is really evident in the rain because the moisture will short out the coil...stop the bike..and when it dries out, the bike runs again.

    Bean can, ICU, spark plugs, and wiring..which part has a headache?. Sometimes include the kill switch and ignition key if the wiring is really old or been hacked to death.
    #16
  17. GoBrave

    GoBrave Been here awhile

    Joined:
    Apr 4, 2017
    Oddometer:
    152
    Location:
    Ontario Canada
    image.jpg Well here is problem #1

    I wonder if the bracket needs to be grounded? One side broke right off!
    #17
  18. Beemerguru

    Beemerguru Beemerguru...G/S guy

    Joined:
    Nov 7, 2006
    Oddometer:
    1,920
    Location:
    Redwood City, CA
    Back up a little so we have a better perspective.

    The bracket for the ICU isn't a ground connection....but that doesn't look like the stock bracket from that picture
    #18
  19. GoBrave

    GoBrave Been here awhile

    Joined:
    Apr 4, 2017
    Oddometer:
    152
    Location:
    Ontario Canada
    bike2.png No it's not the stock bracket that came with the Red Center. To be honest I don't remember why I couldn't use it. The wire harness is bulky and would not fit between the coils. So the bracket I made moves it back enough to fit. But now it interferes with the tool box! I need to make a new one. I see I can make it a little tighter and wider for the extra strength needed.



    This is the only other pic I have so far!
    #19
  20. Beemerguru

    Beemerguru Beemerguru...G/S guy

    Joined:
    Nov 7, 2006
    Oddometer:
    1,920
    Location:
    Redwood City, CA
    So what's mounted in front of the coils? Where the ICU is usually located?
    #20