What am I feeling?

[skeenut]

First of all I'd like to thank all on the board who helped me decide between two bikes. I went with the Cross Country BMW in Metucheon used 2004 R1100S with about 14K.

I picked it up about two weeks ago, rode if for a week and then had to garage it to have some minor abdominal surgery and recover for a week.

Which brings us to today. Went out for a quick 40 mile recuperative ride and darn if I didn't feel it...I though I felt it when I first rode the scoot but didn't believe myself.

With a "soft" hand on the throttle at between 3K and 4K in any gear up to third I get pronounced short duration, like one second, dare I say it....SURGES???? I've noticed it on the flats, on hills, entering corners (kind of scary once) even while engine braking.

I thought the twin plug bikes were free of surging.

By way of background, I've always ridden BMW's; an R65LS, an R100RS, a K75S, a K75RT, R1100GS and several Honda GB500's and a Suzuki SV650. There's a Buell Blast in there somewhere too. I've never felt this before.

What is it, and more importantly, how do I make it go away?

TIA,
Jeff

[signit98]

...Throttle Body Sunch will take most - if not all - of it out... seems to be the general cure for this kind of thing... worked on mine twice now (even though it suck that is has to happen that often) and is easy to do... do asearch on the topic.

[Steve Carlton]

I'd ask the dealer to do it. It's no big deal, and you shouldn't have to deal with it right off the lot.

[VetteRacer]

Sync TBs and check/replace spark plugs. Maybe check filter out while at it..
Or try to have the dealer do it as said above.
Goodluck, hope it helps!

[Bob Hancock]

valves first....then TB sync, then it get's more vigorous if still there. Talk to the dealer first.

[on2wheels52]

Valve adjust and TB sync got rid of my right hand getting numb after an hour of riding also. No surging on the S, my little GS has some minor, almost surging, issues when not fully warmed up but am too far from a dealer to warrant a trip.
Jim

[tomn]

what happened to good home remedy of surging by using 4 anode tipped Bosch Platinum plugs, a little more than 2 anode tip plugs. this was a rage on all R bikes with single spark, I wasn't around this site back then so I don't know how S would behave with this substitution.

[skeenut]

OK, I'm gonna try the easiest thing first since I've never done a valve adjustment and don't own a TwinMax unit: I'm gonna change the plugs.

This is aquote from Rob Lenitini's IBMWR article Zero = Zero, Note: "Oilhead" BMW spark plugs are Bosch FR6DDC of dual "side electrode" configuration. The author has found that standard "over the center electrode" plugs, specifically Autolite 3923, contribute to smoother running and less surge. Simply replacing the OEM Bosch plugs with the Autolite 3923 gapped to .028" could solve some surging and obviate the need for TPS adjustment.

We'll see.

Thanks again all,

Jeff

[gigantic]

don't ride between 3-4k rpm= no surging!

[skeenut]

Before anyone gets overly concerned about me replacing plugs without verifying part numbers re: the Lentini article I quoted above, well I HAVE researched the correct part numbers for the plugs. They are 2 Bosch FR6KDEO 14mm plugs and 2 Bosch YR6LDE 12mm plugs.

Best,
Jeff

[VetteRacer]

Jeff, I think IBMWR has a decent write-up on valve adjustments. It is VERY easy to do. As long as you have feeler guages ($4.99 at parts store) your capable of doing the job.
And you have to remove the plugs to do it anyways, so its a 2 for 1...
Best of luck.
Matt

[Steve Carlton]

Do you know the service history on yours, Jeff? Valves/synch are due every 6,000 miles.

[skeenut]

Steve,

I am going to get a detailed history from CCBMW. Perhaps it is due.....