Possessed R1200GS sorted
BMW mechanic Ian Joyce had his work cut out checking for dodgy wiring
BMW’s GS is popular for its ability to mile-munch and the owner of this 2009 R1200GS, Sebastien Talar, had put 20,000 miles on his bike in three years.
“I use it 365 days a year and it never missed a beat, but one day it just stopped with an electrical failure,” he said. “When we started to test the electrics, I thought it was possessed and I’d have to bring a vicar in for an exorcism”
Ian Joyce, owner of Bike Motor Works near Grendon, Northants, was called in to help. The ex-BMW workshop manager told us: “It would power up the dash, go blank, try to start, then show flat battery signs. It was crazy.”
With CANbus systems, it’s tricky to work out whether it’s a programming issue or a wiring fault, but Ian had a spare central control module and when that didn’t sort out the misbehaving machine, he went down the wiring route.
“Every wire was checked. Sometimes I’d get the reading I’d expect, then 30 seconds later it would go wrong. In the end I locked onto a main live feed up towards the ignition that kept appearing and disappearing.”
To get at that suspect wire he started at the front where all the main electrics are and cut back the loom cloth tape until he got to a point under the rider’s seat where a bunch of wires were really tightly cable-tied to a frame post. As he bent each wire back, their insulation cracked and green oxide seeped out.
“BMW have history when it comes to overtightening cable-ties, I’ve seen a few BMW bulletins about loosening them off,” Ian said.
Once Ian had tracked down the issue, it was pretty straightforward for him construct a new sub loom, cutting the wires back to get a good solder. This job came in at £700 allin, while a new loom alone is £1200.
‘It would try to start then show a flat battery’