How to Turn a GS1200 or GS1250 Into a Real Adventure Bike – Part 1

GS riders cop a lot of flack from the rest of us, but it’s only fair.

If I showed up to a cross-country horse event on an elephant and rode it to the nearest café while shouting “I’m a horse rider too”, you’d look at me like I was a cyclist in lycra, holding up traffic and pretending I’m a legitimate road user. The only confusion between those two examples is to wonder which one is the biggest wanker.

But fret not, hope is not lost. While you can’t turn an elephant into a horse, it turns out you can turn it into a smaller, lighter and much better handling elephant that can ride with the horses in most terrain.

We recently bought a 2009 GS1200 and have been making it our mission to ride it as hard as we can. I have just gotten back from a week long ride through the Outback/desert in Western Australia with a bunch of my enduro mates who were all on their enduro bikes, with the threat of violence and owing beer if I held them up. There’s a long way to go from stock to turn it into a bike worth thrashing, but what I did see was a lot of potential. We’re documenting the changes we make as we go, to create this series on “adventurising” a GS1200.

Before we worry about changing handling, ergonomics and capability, we need to first work on reliability which is what we cover in this Part 1. As it turns out, the people running the elephant shop, know that most people buying them are only using them for road touring and occasional gravel road use and they’re built accordingly but marketed as a serious off-road machine. The engine on a GS is a beautiful thing in terms of its reliability and service intervals. Aside from the sheer weight and size, I can’t fault the engine. The feel and handling of the engine is also beautiful. Mainly, it’s all the accessories that are the problem. With so many additional components compared to other adventure bikes, it’s not surprising that there’s a few things that tend to go wrong. Here’s how to pre-empt or fix some of the issues a GS1200 or GS1250 has when used as a real adventure bike.

Immobiliser and Key Issues

Order a Spare Key and Leave it With a Friend

A GS1200 is the worst bike in the world to own, if you lose the key. Even if you bypass the steering lock and hot-wire the bike, all you’ll get is the dreaded EWS notification on the dash, meaning it hasn’t been immobilised and will not start. GS1200s have an antenna ring around the ignition that reads an immobiliser chip inside the key. Later model GS1250s have the same sort of thing, but it’s a wireless fob.

Either way, on both bikes the immobiliser is coded into the ECU. Only a key that’s programmed to match the VIN will match that ECU and let the bike run.

If you lose your key, or just want an extra, they can only be coded at the BMW factory in Munich, so you’ll be waiting for a shipment from Germany just to start your bike if you lose the key. This isn’t good if you’re in the middle of the Australian Outback or on the side of the Pan Americana in Peru.

If you’re going on a long trip, take your spare key with you. If you bought the bike new, there should also be a plastic key for emergencies which isn’t an actual key, but does have the EWS chip so you can start the bike.
It might be worth leaving that key, or ordering a spare from BMW, and leaving it with a friend who can send it to you in case something happens to both your keys while you’re on the road. At least that weay you’re only waiting a few days on express post rather than for weeks for a key from Germany. The other problem with waiting for a spare is that you have to show proof of ownership at a dealer to order the new key, which might be impossible from the ass-end of nowhere.

Antenna Ring Replacement

The antenna ring which reads the EWS chip in the key, was subject to a recall for certain manufacturing years. I believe those years were 2007 to 2009, but I would quote your VIN to a dealer and double check.

The newer “247” rings, based on the 247 suffix of the serial number of the post-recall replacements, are said to be quite reliable. However, as there’s no way to bypass the EWS on these bike, it does create a potential for a complete show stopper. For a genuine BMW part, the antenna rings are surprisingly cheap at about $50USD (I paid $75AUD), so you may as well get a spare and take it with you.

For the low price, the small size and the ability for your bike to become a brick if you break this part, I strongly recommend taking a spare on any long, remote ride.

Fuel Systems

Replace the Fuel Pump Flange

A belt driven alternator does give one the suspicion that the GS series was built by someone from BMW’s car department. Large, bulky fuel pumps and sender units add to that impression.

I come from a world of motorbikes that have gravity-fed fuel where a small leak is just a small leak. Add a fuel pump the size of what my daily-drive car has, and a small fuel leak becomes a pool of petrol that overflows from the top of the tank and drips straight on to the red-hot header pipe.

GS1200s have had three notable issues causing fuel leaks and several recalls, but not addressing every problem. The first recall was for bikes from 2005 to 2011 for the plate that screws into the top of the tank and holds the fuel pump. Due to manufacturing issues or the material used, it led to cracking around the flange where the quick connect fitting screws into the plate for fuel to be pumped to the injectors. The second recall, for bikes from 2011 – 2014, was for the same issue but was caused by over-tightening of the fitting with pneumatic tools, rather than a defect in the plate itself. I believe there has also been a recent recall for similar issues, but I’m not sure which manufacturing years that covers.

So, you can either look up the recalls and see if you’re bike was or should be covered by the recall or call your local BMW dealer. My bike was included in the recall, but never had the work done to it. As I was in a rush to go on a ride, I just repaired it with petrol resistant epoxy.

Replace the Quick Connect Fuel Fittings

The third issue seems quite widespread but has never been addressed by a recall. I’ve had this problem and there’s countless posts on forums of people with the same issues. The quick connect fittings that go into the aforementioned flange, allow for the fuel hose to be easily connected and disconnected from the tank.

After repairing the flange, it was still leaking so I changed the O-ring on the quick connect which did nothing. Having a closer look, I could see that there was a lot of hairline cracks in the perished and now brittle plastic that the fitting is made from. After meticulous work with CA glue (super glue) and an activator spray I have for woodworking, I was able to fix every crack. I then put it back in the tank and while tightening it to a suitable torque, the top half of the fitting snapped off from the bottom, threaded half. It seems that the plastic either doesn’t age well or is not petrol resistant.

I bought a set of stainless steel quick connect replacement fittings. It comes as a whole set from Munich Motorcycles including spare o-rings and a petrol resistant thread sealer. The Gasoila thread sealer takes thirty minutes to become tacky before you can insert then fitting and then needs to be left overnight. I needed to ride the bike the next morning so I needed to know quickly if it was fixed which meant not waiting overnight before starting the bike. I bought an aviation gasket compound from Loctite because it’s petrol resistant and works in pressurised environments. It worked perfectly.

See you in part 2 of How to Turn a GS Into a Real Adventure Bike.