Surging,

[MrFeldman]

A buddy of mine just bought a '96 R1100rs w/ 84k meticulously maintained mi. on the odometer. It's a high miler, but the seller was a maintenance freak! The bike is in incredible shape. My buddy has just begin to notice a slight surging at steady speed,...particularly low speed, but any time he's holding steady he gets a bit of throttle hesitation or surging, is this common for 80,000 plus miles ? And is there an easy fix?, I know it's an 1100rs, but the engine config is almost identical to the 1100s.

[jduke]

Very common in the early R1100's, mostly around 4200 rpm in 5th gear.
First is a very careful valve adjustment and a precise throttle body synch.
If this doesn't do it, a zero=zero is the next step.
There's a lot on this over at IBMWR.org
I don't think there was ever an official explanation of what caused this, but I heard it was a combination lean condition, single o2 sensor, and a slow to respond ECU.
If the valve adj. and synch doesn't do it, and the zero=zero doesnt fixt it, then some kind of chip would be the next step.

[Meeni]

Later engines had a second plug added to fix this and other glitches.

[wiggledbits]

Maybe a lame question but could someone define levels or surging? Mine bike (2004 11S) surges in at least 2nd and 3rd gears at ~3200-~3800 rpm. I wouldn't call it dangerous more annoying with a give and go alternating about 1 or 2 seconds apart. Is there surging where there are noticeable changes in speed. Over the past couple of weeks (since having a shop go over the bike after purchase for the 12k service :-( ) I haven't noticed it getting worse but will it if I don't take care of it? Like I wrote above it is at this point a bit annoying but doesn't affect the ability to control the bike or speed.

[bill pierce]

Originally Posted by MrFeldman

My buddy has just begin to notice a slight surging at steady speed,...particularly low speed, but any time he's holding steady he gets a bit of throttle hesitation or surging, is this common for 80,000 plus miles ? And is there an easy fix?, I know it's an 1100rs, but the engine config is almost identical to the 1100s.

Rich,

My s surged pretty bad when i bought it. A careful tune should fix it. If your buddy is local give me a call and we'll get together and do a throttle body sync and valve adjust on me.

[MrFeldman]

Originally Posted by bill pierce

Rich,

My s surged pretty bad when i bought it. A careful tune should fix it. If your buddy is local give me a call and we'll get together and do a throttle body sync and valve adjust on me.

Thanks Bill, he is a local Spokane rider, I'll give you call this Sat/Sun.

[Rapid Dog]

...Feld, after you do all the suggested stuff, get a Techlusion box (fuel nanny) and just set it to add fuel at the low range. Pretty sure you'll get some positive results.

[phoenixtexoma]

A no-adjustment, plug-and-play FRK is also worth taking a look at. FWIW, I used Techlusions on my 2 other oilheads with great results. My S just seems to be partial to the FRK.

[Rapid Dog]

...not sure FRK makes a plug for that old a bike though...

[bill pierce]

So we worked on this bike a few hours on Sunday afternoon. It's better but there is still a little stumble right off idle.

I was thinking vacuum leak, but the rubber manifolds between the throttle bodies and heads look good. So I suggested having the injectors cleaned.

Any other thoughts on this?

Thanks

[Guest24]

I'd spray a little starting ether around that potential vacuum leak area just to make sure before I pulled the injectors. See if you get a rise in RPM.

[jduke]

Did you replace the plugs with Autolite 3923's?

[bikerfish1100]

not positive if it existed on the RS models, but pulling the pink cat code plug on early RTs was a generally recognized fix (when the valve adjust, Autolite plugs & TBS failed to fully deliver).
R11S was generally impervious to surging (given good tuneup) due to differences in exhaust system and ECU.

[JimMoore]

Yeah, pull the ccp and throw it in the garbage.