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r1100S Terrible running and I'm stumped

Discussion in 'Road Warriors' started by benjbeiler, Mar 25, 2020.

  1. benjbeiler

    benjbeiler Been here awhile

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    Hello all, I am not sure quite where I should put this, but it seems most oilhead wisdom resides here. My question is regarding a 1999 R1100s with about 38,000 miles. My apologies in advance if this is the wrong place, and many thanks for any help y'all can give! I'm also posting this in the R1100s specific forum over in Road Warriors.

    Here is the deal:
    I bought the bike wrecked (front end collision) and after about a year of sitting around, finally got it fixed and started riding it. My first Beemer cause I've always been scared of them because of my dad's RT always needing work done. :) I'm not a pro mechanic by any means, but I'm not scared of taking my bikes apart either. That said, this bike is a hoot to ride, and his bike has well over 100k.

    Several weeks ago I was out on a ride, and thought I felt a little surging. Nothing crazy, but seemed a bit off. The next few times I was out it got progressively worse, till it basically wouldn't run. When I would roll on the throttle it would almost die, then kind of catch and go again. It also started idling terribly. It really felt like it wasn't getting fuel. So... I pulled it apart to check some things. In pursuit of this I thought a little maintenance would be in order, so I started replacing some things as well. So far I have:

    -Installed new spark plugs (basic autolite ones)
    -Installed new spark plug wires (sorry if I use the wrong names for things)
    -Checked compression (about 155 on the left, 157 on the right, WOT)
    -Checked spark (removed boot, installed old spark plug, and held it to cylinder head) Both sides spark away, brightly, but I'm not an expert at diagnosing exactly what they should look like. Looks to me like it's sparking like crazy!
    -Replaced my HES (BOSCH aftermarket from BeemerBoneyard). Used instructions on this site. Old one was a bit flaky on the wiring, but didn't seem horrible, and TBH I thought that this was going to be the problem, but no difference afterwards
    -New fuel pump
    -New fuel hoses in tank
    -Fuel filter was changed less than 1k ago
    -Pulled injectors and cranked bike. Again, I'm not a pro, so not entirely sure what perfect injectors would look like, but they definitely spray fuel.
    -Throttle bodies were balanced in the last 1k

    Basically, it starts really hard, and you have to play with the throttle to keep it going. I feel like I may smell more gas than usual? If you try to ride it, and roll on the throttle, it basically won't rev and won't pull. If you lay of the throttle the idle goes lower for a sec and the bike stops. I'm pretty sure this part is key, I noticed the last time or two, and now more frequently, a popping sound that I would say is likely from the left cylinder. Almost like an air whoosh, but not really. I wouldn't say it's a knock. Maybe it was just in my head, but the last time I started it to listen to it, I almost think I felt air blow down by the left cylinder.

    So... any thots? Ask any questions and I'll try to answer them, clarify, etc... I'm stumped. I have spark, fuel, and compression... But something is way wrong! Seems electrical or maybe some kind of a vacuum leak? I definitely don't know, and I'm aching to fix this bugger! :) Could I have messed the timing up when I replaced the HES? But the problem existed before that...

    Thanks!
    Benji
    #1
  2. Seapbmw

    Seapbmw Adventurer

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    I had an eerily similar problem with an older airhead, I started down the same path of “troubleshooting by replacing parts and adjusting things” to no avail. After another frustrating ride I noticed my right boot smelled like gas, I had checked and replaced the intake tubes bit didn’t check the metal sleeve the tube attached to. Turns out it was loose in the head. Tightened this sleeve, problem solved. Not sure if the oilheads have this sleeve but its worth checking, your symptoms sound like an air intake leak.

    good luck and keep us posted!
    #2
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  3. JimVonBaden

    JimVonBaden "Cool" Aid! Supporter

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    [​IMG]
    #3
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  4. PaulBarton

    PaulBarton Long timer Supporter

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    Ok - I’m gonna shoot for the easy one first...

    made your throttle cables seated properly? This is a very common issue and can lead to lots of unnecessary troubleshooting.

    If your HES had flaky wiring it was bound to fail eventually. You can have @GS Addict rewire that one for a spare.

    I recently had an issue with my 1150GS where I replaced plugs and plug wires. I was about to replace the coil but it tested in the right range so I kept trouble shooting before dropping $100. I have a spare tank so I swapped tanks and problem went away. I opened up the tank and discovered that my brand new internal hoses had developed a crack due to my handy work. I replaced the faulty hose and corrected the causative issue and now all is good. I share that because just because the internal hoses/filter/pump are new doesn’t exclude them from consideration.

    Edit: in my long winded response, JVB beat me to it and with pics.
    #4
  5. ExodusRider

    ExodusRider ExodusRider

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    You've done quite abit of troubleshooting looks like.

    Good battery, spark, fuel delivery and compression. I'm leaning toward possible vaccum leak?

    Check vaccum port on right cylinder ?
    At least I know my watercooled has one where the vacuum port connected to the charcoal canister.

    When I removed the canister, i plugged the port.. few months later..it was idling pretty bad.. kept dying unless i held throttle open... ie. Too much air..needed more fuel..

    Took forever for me to trace back that the hose plug I installed had popped off.

    In any case.. good possiblity somewhere an in-take blockage or vacuum line there might be a leak?

    Last thing to check.. cam chain position sensor perhaps? If its defective.. might not allow to rev up a certain RPM..

    just a few thoughts. Good luck and keep at it.. you'll straighten her out... let us know what u find..
    #5
  6. benjbeiler

    benjbeiler Been here awhile

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    Man, you guys are quick! This is awesome! Thanks!

    @Seapbmw, I don't know anything about this. Maybe someone can give me some more info if this is something on the Oilheads?

    @JimVonBaden Thanks! Those are good now, but when I first had the bike it ran roughly, and I came on here and found a pic you had posted on a thread, and sure enough, that was the problem. So thanks! I also found some of your advice different places on the HES removal and replacement very helpful. Cheers!

    @PaulBarton I think I'm good on those items, but as you said, ya never know. So what is the difference in the coil and the spark plug wires on an oilhead? I had kind of concluded on my bike what I call spark plug wires is referred to as the coil?

    @ExodusRider This may be something. More and more I'm leaning in this direction. I found out in all this that my charcoal canister is removed. Anyone got any pics of any ports that should be plugged if that is done on an oilhead? Might be something like that. I'll look for instructions/ pics on these items, but anything any of you have about vacuum leaks, etc. may be helpful.

    Thanks all!
    Benji
    #6
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  7. benjbeiler

    benjbeiler Been here awhile

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    Also, is what exodusrider and seapbmw saying perhaps related?

    Sorry, I'm clueless on some of these things... Got loads to learn!
    #7
  8. Crazybrian

    Crazybrian Resident Moose

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    Still have the stock exhaust? Pull the cat off, sounds like its clogged.
    #8
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  9. ExodusRider

    ExodusRider ExodusRider

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    This is what / where the port is on the right cylinder of a LC; gonna assume if there is one for your model.. would be close by?..

    If it's unplugged.. would look like a nipple/ port that a vacuum or fuel line might attach to..

    If you see line / hose there, just make sure they are tight.. worth a check.

    I have a 2 inch hose terminated at the end hidden away.

    20200325_215817.jpg 20200325_215757.jpg
    #9
  10. benjbeiler

    benjbeiler Been here awhile

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    Would that require a new y pipe? Got any more links or info on clogged cats?

    Thanks!
    #10
  11. Crazybrian

    Crazybrian Resident Moose

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    Do you have a y pipe or cat? Ive had 4 different vehicle have the same symptoms from a clogged catalytic converter.
    #11
  12. PaulBarton

    PaulBarton Long timer Supporter

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    Benji - As you seem comfortable jumping into the mechanical side of motorcycle maintenance yet are unfamiliar with the BMW oilhead and some of the terminology you would do well to purchase the JVB (Jim Von Baden) maintenance/repair dvd for your bike. I believe he has a vendor thread. He also has a website to purchase them.

    the plug wires are the plug wires or HT lines. They connect the spark plug to the coil. The coil is located at the other end (away from the spark plug) of the plug wire. With 100K on the bike it's conceivable that you are experiencing issues with yours. You can remove it and test the resistance of the primary and secondary coils. That won't be a definitive test though as the coil can test properly at rest but under load could prove faulty. The only real test is to replace it and see if the issue goes away. That's why I chose to continue with troubleshooting before dropping $100 on a "maybe."

    For the vacuum ports, they are located on the bottom of the throttle bodies and should have a little rubber cap on them. These are the ports for syncing the TB's. If you have a port uncapped during operation it will create a vacuum leak and poor running. You should be able to see them on the bottom of each throttle body. It is a "brass" stem and should have a black rubber cap on it. The carbon canister on the oilhead was connected through the in-tank fuel overflow and vent lines.

    You say you were "smelling gas" are there any signs of external leaks? Your external lines could be faulty. Do you have quick disconnects on the lines? At the tank plate (inside right tank lobe), there should be 2 large diameter fuel lines -- one is the fuel delivery line and the other is the fuel return line. The fuel delivery line goes to the fuel rail which feeds the throttle bodies. The Fuel Return line returns the unused fuel back to the tank. A crack anywhere along these lines would cause a drop in pressure and affect the performance. However, you would also see evidence of a leak (and smell). You should inspect these lines to confirm they are not compromised. You indicated the fuel injectors were spraying fuel. There is a test to determine that they are passing the correct amount of fuel. I'm not recalling the correct volume right now but a search on this site will turn it up pretty quickly. Depending on the results of that test or maybe "just because" you could clean the injectors.

    Did you do the work inside the tank? If not, why are you confident in it? I'm not saying it's bad but it could be.

    I think you had asked a question about timing. The oilhead timing has a fairly limited range of adjustment for the timing so unlikely you messed it up enough to cause the problems you describe.

    When you "felt air blow down by the left cylinder" where was it coming out of? Are the throttle body tubes air tight at both the cylinder and the airbox? When was the air filter changed last?
    #12
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  13. benjbeiler

    benjbeiler Been here awhile

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    I just went and looked at it again. It's got a cat.

    So... Can I drop the cat and see if it runs? Or will that mess with other items?

    In other words, can I just disconnect it to check if that s the problem, before dropping the coin on a new y pipe?
    #13
  14. PaulBarton

    PaulBarton Long timer Supporter

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    If you remove it you can inspect it to see if it's clogged. Typically a baffle has broken loose and it will rattlle. I understood that part of your symptoms was the bike would "stop" (which I interpret to mean stalls/dies). Typically a clogged cat would "restrain" the engine/throttle response meaning that as you open the throttle the clogged cat creates exhaust pressure which restricts the engine power. When you release the throttle the pressure ebbs. This usually allows the engine to idle properly but you have restricted power or a hesitation under load.

    Running it with just open headers will destroy any relationship you have with your neighbors ;-). It will be quite loud especially if you test it under throttle.
    #14
  15. benjbeiler

    benjbeiler Been here awhile

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    @PaulBarton
    The service manuals from JVB are a great suggestion. I'll check it out. That would be worth it...

    Duh on the coils. I should have realized that. I'll definitely check them. And maybe just buy new... I am throwing money at it anyway... Thanks for a great easy explanation on that one.

    Ok, vacuum ports are good. I didn't know what they are called. I've doble checked them.

    Fuel lines: mine are new, inside and out. I just replaced them. I was convinced it was a gas issue until recently. I don't have quick disconnects, I used the Beemer boneyard kit. On my fuel tank both vent lines simply go to vent, canister is removed. I did the work inside the tank, have been in there quite a bit recently, I could have screwed it up, but I'm betting I didn't. It's all triple checked, all new... I likely will clean my injectors tomorrow... Good advice.

    Thanks for the answer on timing, that's what I thot...

    On the air, I'm not sure. Could have been in my head. Yes, stuff is tight on both ends...

    Just cleaned the air filter (blew it out) looks to be stock.

    Thanks for all the great responses! I'm starting to think I'll get it licked yet!
    #15
  16. benjbeiler

    benjbeiler Been here awhile

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    Gotcha. It won't even idle right, and starts hard. Would those be symptoms? Maybe severely clogged?

    I'll be dropping it to check it, and my neighbors are great, they will likely forgive me :)
    #16
  17. benjbeiler

    benjbeiler Been here awhile

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    Oh, another question. I definitely have spark on both sides. If I have spark can it be a bad coil? I was thinking a bad coil would give me no spark?

    Thanks
    #17
  18. PaulBarton

    PaulBarton Long timer Supporter

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    Unless it's intermittent, it's likely not your coil.

    I think I misread something in your initial post...your bike only has 38K (it's your dad's bike that has over 100K?). So, yours is a relatively low-mile restored wreck...how long did you have it running before the symptoms developed? Did it run "great" for a while and then the surging started or ???

    You do realize the oilheads are renowned for surging at roughly 3500 rpms, right? That doesn't explain the later symptoms but...

    The electrical connector from the tank to the bike are snugged up tight?

    How was the wiring inside the tank at the pump plate?

    What specifically was the damage to the bike and what was repaired/replaced?
    #18
  19. benjbeiler

    benjbeiler Been here awhile

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    Corre
    Yes, mine is low mileage.

    Yes, I'm aware of surging issues on these bikes. This thing ran awesome for about 3000 miles than this started.

    Yup, tank electrical is good, connection inside and out solid.

    It was a front end collision. The engine still ran when I bought it. New forks, headlights, faring support, oil cooler, telelever, etc...
    #19
  20. benjbeiler

    benjbeiler Been here awhile

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    Oh, another detail that may be important. I forgot to say this earlier. I replaced the fuel pump on the recommendation of a friend several days ago, (after the problem started), but before doing the HES.

    When I had it apart, I blew through the fuel filter to see how that felt. I'd say it was pretty easy to blow through, just a good puff. The fuel filter has about 1000 miles on it.

    I started it up after that work, and thought it was fixed. Ran normally I thought. Ran it about a mile to the station for gas, filled it, and on the way home it started jerking/ popping again. Almost thot it wouldn't make it home. So maybe intermittent? But only that once has it worked correctly.

    After that I decided it was the Hall Effect Sensor, and replaced that to no avail.

    Another note, the wiring loom on this bike has the deteriorating cover typical of these years (at least from looking online seems to be common). Maybe a dumb wire somewhere? I'm in the process of tracing wires...
    #20