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96 R1100 RT - things that go bump in the morning

paed

New member
Experienced this on my last 2 rides. Bike starts, sounds and drives normal at start of trip. Within 1-3 miles of house, bike coming up to operating temp (4 bars on RID), accelerating slowly in 2nd or 3rd gear, feel and hear a distinct bump in the drive train AND the bike surges forward briefly. Bike then runs perfectly for 200 mile back road trip. In fact, it's a joy to ride. Clock is at 60K with last major service (clutch, brake lines, both shocks etc.) done by Tom Cutter @ 45K. The bump/clunk "feels and sounds" like it's originating somewhere in the rear drive. Like I said, I get the ONE bump and the bike runs perfectly normal after this occurs.

Anyone familiar with this scenario? Possibilities I'm mulling: A wonky universal joint settling into a happy place? Less possible, a sticky brake piston freeing up? Still got a solid month of good riding weather to enjoy, so hopefully the solution can be a winter project. :scratch
 
I haven't worked on that model in years but I'd look hard at the clutch control and clutch, maybe just a service /cleaning. Something might be just slightly hanging up and then engaging clutch. just a thought.
 
I haven't worked on that model in years but I'd look hard at the clutch control and clutch, maybe just a service /cleaning. Something might be just slightly hanging up and then engaging clutch. just a thought.

Could very well be the clutch as you describe. Been meaning to replace the Clutch cable as PM. I will order one.
 
If it was clutch-related, I think it would happen sooner - like as you first pull out of the driveway - and more often. Can you roll the bike down a long hill with the engine off, to maybe hear more from the rear? Maybe even shift it a few times, with the clutch lever pulled in, and then maybe with a little bit of slipping friction (to get the "wheel" movement up into the trans).

Can't say if this is the "why", but a while back, Roger04RT posted a graph of the fuel mapping of an early oilhead from startup to the first three or four minutes. It showed that, at about the two-minute mark, the computer made a significant change to the mix, "possibly" as the temperature or O2 sensor came up to operating temp.

ALSO - Note that some early oilheads had transmission issues - including mine, a '97 - that showed up as the trans either finding a false neutral between 2nd and 3rd, or just rejecting that shift completely.

SEE: http://largiader.com/tech/oiltrans/
 
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If it was clutch-related, I think it would happen sooner - like as you first pull out of the driveway - and more often. Can you roll the bike down a long hill with the engine off, to maybe hear more from the rear? Maybe even shift it a few times, with the clutch lever pulled in, and then maybe with a little bit of slipping friction (to get the "wheel" movement up into the trans).

Can't say if this is the "why", but a while back, Roger04RT posted a graph of the fuel mapping of an early oilhead from startup to the first three or four minutes. It showed that, at about the two-minute mark, the computer made a significant change to the mix, "possibly" as the temperature or O2 sensor came up to operating temp.

ALSO - Note that some early oilheads had transmission issues - including mine, a '97 - that showed up as the trans either finding a false neutral between 2nd and 3rd, or just rejecting that shift completely.

I will try the downhill roll with engine off to see if I can hear anything from the drive train.
 
me too

so I have a 96 r1100rt and have been experiencing a similar hesitation/ kick from my bike. It seems as if it dropped gear for a split second and then kicks forward. I seem to only get it in second and more apt to experience it if its lower on rpm ( what i would consider luggin on this bike like 2-3k) but not only at lower rpm and it does not happen more than once when in that gear. its almost as it you tried to start it in gear with out holding the clutch in of course since its moving its no where near as strong. I suspected it was something to do with the clutch hanging up, but it doesn't seem to matter how much power I'm putting down or even if i slam it into gear with power ( Was thinking maybe it was at the end of its life). does this happen to you while shifting or when you are in gear already (mine is while already in gear) but like your bike ever thing else seems to be functioning great
 
so I have a 96 r1100rt and have been experiencing a similar hesitation/ kick from my bike. It seems as if it dropped gear for a split second and then kicks forward. I seem to only get it in second and more apt to experience it if its lower on rpm ( what i would consider luggin on this bike like 2-3k) but not only at lower rpm and it does not happen more than once when in that gear. its almost as it you tried to start it in gear with out holding the clutch in of course since its moving its no where near as strong. I suspected it was something to do with the clutch hanging up, but it doesn't seem to matter how much power I'm putting down or even if i slam it into gear with power ( Was thinking maybe it was at the end of its life). does this happen to you while shifting or when you are in gear already (mine is while already in gear) but like your bike ever thing else seems to be functioning great

My 94 does the same thing when going from first to second. Mostly though when down shifting to second from third under strain. I've found if I hold the clutch lever with just a little pressure on it while the engine engages completely eliminates the surging. Very seldom get the surging going up in years but almost always when down shifting into second so have had to retrain my mental clutch lever movement to slow release.
 
revisited

If it was clutch-related, I think it would happen sooner - like as you first pull out of the driveway - and more often. Can you roll the bike down a long hill with the engine off, to maybe hear more from the rear? Maybe even shift it a few times, with the clutch lever pulled in, and then maybe with a little bit of slipping friction (to get the "wheel" movement up into the trans).

Can't say if this is the "why", but a while back, Roger04RT posted a graph of the fuel mapping of an early oilhead from startup to the first three or four minutes. It showed that, at about the two-minute mark, the computer made a significant change to the mix, "possibly" as the temperature or O2 sensor came up to operating temp.

ALSO - Note that some early oilheads had transmission issues - including mine, a '97 - that showed up as the trans either finding a false neutral between 2nd and 3rd, or just rejecting that shift completely.

SEE: http://largiader.com/tech/oiltrans/

For my machine, I've convinced myself that the issue is indeed the fuel mapping as described above. In my case, the bump/surge ALWAYS has occured within a few minutes of leaving the driveway, then the bike runs flawlessly. I can only speculate on why I did not take notice of this anomaly in the past. State of tune? On my most recent ride, I noted a milder bump/surge then previous. In any event, I've brought myself peace-of-mind and can continue to ride it like I stole it!!!
 
For my machine, I've convinced myself that the issue is indeed the fuel mapping as described above. In my case, the bump/surge ALWAYS has occured within a few minutes of leaving the driveway, then the bike runs flawlessly. I can only speculate on why I did not take notice of this anomaly in the past. State of tune? On my most recent ride, I noted a milder bump/surge then previous. In any event, I've brought myself peace-of-mind and can continue to ride it like I stole it!!!

my issue may be a totally different one but with similar symptoms as mine will continue the issue. I plan on checking valves and doing throttle bodies soon ( they are now due )we will see if i find anything or it has any effect. I believe the throttle bodies are a bit off.
 
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