1150gs Surging
 

I ride an 1150gs adventure 2004. When in low gears 1st & 2nd at low speed I get engine surging very annoying when riding slow standing up off road, I understand that this is a common problem with the 1150. Can any one suggest a cure. I have heard of people that have fitted power commander or other after market stuff.

Peter

On the R1100 this is a common problem. The solution is provided by the BMW riders club of the USA (sorry, don't remember the correct name). There are documents on their website. Search for words like "zero-zero" "BMW" and "motronic". Fixed our R1100RS quite nicely. Basically, the FI is running too lean and you reset the thing correctly, which makes it run richer. You kill your warranty, though, if BMW find out.

Ours was so bad it was like trying to ride a bucking horse when going around roundabouts.

surging issue
 

Hi Peter
I own a '03 1150gs and, almost, solved the problem by learning to do the valve timing/spacing and the throttle body sync. When I got good at TBS (both stationary and on the "move") and I was anal 'bout how perfect it should be the surging issue became almost non-existant.

Cheers
Tango six-zero :tank:

Thanks for replys guys ill keep searching the web.

Peter

Peter
Thsi is one of the most discussed issues with the BMW oil cooled boxers. Once you start surging you will find tons of discussions some highly technical and other ' snake oil smoke and mirror' suggestions. The problem with surging originates from the engine running a bit lean to meet stringent emmission controls. I've tried all sorts of things to cure this but there are 3 main areas to focus on.
1) good valve adjustment
2) Good throttle body balancing
3) Getting rid of the cat code plug

Number 3 was the most dramatic imrpovement I experienced as it is this that makes the electronic injection run lean to meet the emission controls. I took mine out and it made a huge difference. The downside is slightly poorer fuel ecomony (only very marginal difference) but you are polluting more than with the car code pug in.
There is a modification made so simple by 'Steptoe' from the UKGSER.com website. Steptoe is the resident GS forum mechanic and his modification to the cat code plug is beatiful in it's simplicity. Here's a picture to show you what he has done to cure the surging problem.
Ride safe
Gecko

Hi Gecko
Many thanks I might try this as its the simplist I have seen so far. I take it this does no damage to the electircs or any thing else.

Peter

Hi Gecko
Just had a look under the seat and I do NOT have a coding pulg fitted. wounder why? May be BMW didnt fit them for 2004.

Peter

Hi Peter
Maybe the previous owner took it out and that may be part of your problem. Different countries had different spec bikes - some with catalytic convertors others without so without knowing the origins of your bike it's hard to say what it should have. I've been running without a CAT code plug on my 1100 for a long while now and no ill effects except the plugs are a bit blacker than is ideal. Some people riding behind me say my exhaust smells of petrol - I just tell them not to ride so close :D
It may be worth your while going onto UKGSER and asking Steptoe b ut definitely the valve adjustment and throttle bodies should be done properly as this will already bring you a good way to solving the dreaded surging.
Cheers
Gecko

Gecko

Thanks, the Bike originally came from Germany (04 spec)to the UK and I brought it when it was about 8 months old from SPC near Alton. It has alway had the surging. It is going into BMW next week for a service so ill see what its like after that. I would like to get rid of the CAT and fit a y piece and can also.
May be I could also try putting a coding plug in it. Is that what it should have in it for running on low grade fuel.

Peter

Here is the link to the articles: http://www.ibmwr.org/r-tech/oilheads/index.shtml

Many thanks Peter
I shall enjoy looking through them. You have some good pictures on your web page looks like a good trip.

Peter.

You're welcome, I hope it helps. The zero adjustment almost cured my girlfriend's 1100RS, but do follow the instructions carefully. Also, I don't know whether anything has changed on the 1150 and 1200 models.

If you break it you own all the parts. ;)

Yes, I'm enjoying my trip again, now that it's warm and balmy on the Aegean coast. I'm not looking forward to Ankara and Eastern Anatolia, cause it'll be cold...

My 2p worth:

Bought a 2001 1150GS in June '04 with 24,000 miles on it, plus Y-piece & Remus. Now on 56,000 miles, it's never surged & only pops & bangs on the overrun if I shut the throttle quickly from higher rpm.

All plugs etc still in place. I check (& adjust if needed) the valave clearances every 6,000 miles before balancing the TB's with a Morgan Carbtune. Never messed about with TPS settings/voltages either.

I recently read a thread that said that Rocker Arm adjustment has an impact on surging? I did as the thread suggested & adjusted mine to a slightly tighter tolerance (0.15mm to 0.08mm) with no difference but didn't really expect anything.

My girlfriend rides an identical bike that surges just a little bit but not enough to be an issue. In fact, I have trouble noticing it unless I actually think about it.

Thanks Steve

i think I need a workshop manual before I start adjusting things I have always done my own mantaince just would like all the right settings etc.

Peter