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Hello....I have enjoyed my 97 R1100RT for the few weeks I have owned it.
It runs quite well, does not seem to have any trace of the "surge" at low speeds, and so on....My question centers on an aspect of the engine running at a steady 70 mph or even more in top gear. Though the engine feels very smooth in such a situation there is a very slight "hesitancy" that is noticeable to me. Best way I can describe it is that it continuously "stutters" EXTREMELY slightly...It's way less than a "missfire" but I notice it...I am thinking it may be characteristic of the boxer engine...

I do not notice it at lower speeds, although I have not paid attention to that matter..

I am thinking that:
1. It may be normal.
2. Might be fuel injection out of sync if there is such a thing.
3. Spark plugs?
4. Valves need adjusting?

anyway, wish I could be more definitive...

Any ideas?

Thank you.

Bob
 

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Well, thanks to all 190 folks who have visited this thread so far, and I am hoping someone will reply, if only to tell me I am asking dumb questions, or that my question is not understandable, whatever.....Please give me a clue.
Sincerely,
Bob
 

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Bob, Since the stumble only occurs at higher RPMs, check the fuel filter. It may be clogged slightly and starving the injectors at higher RPMs.
 

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As Oz said check the fuel filter and in tank lines ( they tend to crack ). Also valve adjust, new plugs and a throttle body sync is always a good start!
 

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if you going to replace the in take fuel hose. DO NOT use regular gates fuel hose or similar from the auto store the inside of the hose may be rated for fuel but the exterior fuel hose is not. be careful about going to the bmw dealer for the hose they will want about $30 a meter.
 

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Always do the simple stuff first. I would buy a can of Chevron TECHRON fuel injection/ carb cleaner and overdose the tank with it and take it for a high speed run. This has always worked for me and has actually cleaned some very clogged up carbs (4) on a past Suzuki Bandit 1200S and saved me the trouble of taking all four carbs off and apart.

A regular shot of SEAFOAM, LUCAS or other FI/ carb cleaner.

Next would be plugs. Then air filters and then adjust the valves and replace any fuel filters.

Ethanol fuel plays heck with fuel systems.

I had a 1999 BMW R1100GS and it enjoyed the occasional sip of fuel cleaner/ conditioner.

Sam:)
 

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Porky does have a point. but on the injection cleaner i would only stick to techron thats all bmw recommends. I would also recomends to watch out for ethanol in the gas. BMW before 2000 hate ethanol
 

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I have this very same problem that Bob describes. At first I thought it was due to wind impacts (an artifact of having a full fairing--I usually ride a naked bike.) Except that it happens at low speeds too. It is like the engine drops one firing out of every 400 revolutions. Or as if there was a sudden burst of air into the intake that leaned out the engine momentarily. A very curious characteristic and I'm glad to see someone else can describe it so I can know I'm not nuts.

Did this ever get resolved?
 

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"Drive by" posters are a pain as they seem to never follow up after they ask their questions.:sad:

BMW air/ oil heads are Sooooooo simple to maintain, work on and fix, his problem was probably an easy repair.

I've had four "R" series and one "K" series BMW's.

Sam:grin:
 

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I own the same year bike. nice bike when runs in most cases always an issue somewhere
Now in your case i beleive strongly that you need to adjsut your valves also check your carbs sync. Check Chris Harris on youtube in his one his latest vidoe he addresses that also my bike has R256 electornic injection module to address your surging issue, i should consider that/
good luck
Thomas
 

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Hi Bokobob

I also have an oil head BMW. The R1100 engine is known to have surge issues, hence BMW added two more spark plugs for the R1150 to solve this. However the most common reason for surging or ruff running on these bike is the break down of ignition coils.

The ignition coils are place inside the cylinder head, hence they get heat cycled every time you run the bike. This is not good for electronic components and they break down over time due to this.
Pull the ignition coils out on both sides, if they look rusty or swollen changes are that you are beginning to see signs of pending failure.

Before buying new ignition coils check the valve clearances and that the throttle bodies are correctly synchronized.
Hope this helps.
 

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On the older RT I will always start fresh and recap those valves also look for techlusion r259 that will straighten your problem.
Good Luck
 
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