BMW R1200RT/R1250RT Forum

Hi all

I have an intermittent starting issue with a new R1250RT (SEP 19 with 1600 miles on the clock).

When I try to start it sounds like the battery does not have enough power to turn the engine over. It tries but gives up. This can happen first thing before going on a ride, or it may start easily and occur during the ride when I have stopped and go to restart. Usually it does restart after a couple of attempts, but recently it took over 20 mins to get restarted.

It can happen wet or dry, warm or cold.

I have a tracker fitted which give me a read out of the bike battery state, always well above 12v. So it is not lack of voltage. I have also had the battery off and recharged it, still the same intermittent fault. The battery connections are secure, not loose.

My bike is now back with the BMW dealer. They put it on charge over the weekend then spent a few days starting it with no problems so are trying to tell me there is nothing wrong. I do not believe it is the battery, so have left it with them, saying that the battery is not the issue.

Has anyone experienced a similar issue? I am aware of someone with a R1250GS having the same problem. Better still does anyone know what the cause might be/is.

Thanks

Stuart

Found this thread on Adventure Rider, https://advrider.com/f/threads/r1250gs- ... m.1418465/ might be helpful.

Hi David, yes I have seen that and sent it to the BMW dealer; still waiting to hear back from them. But thanks anyway.

I had a problems with a Triumph Sprint GT, turns out there was a problem with the tolerances within the starter motor. Triumph changed it under warranty  had no further problems in 30K+

Had the same problem. Dealer fitted new battery. Sorted.

Battery was replaced about 6 weeks ago, but did not resolve the issue.

I sometimes have the same problem on my R1250, seems the starter turns the engine maybe  a 1/4 turn and it stops, I know there is a centrifugal de-compressor on the exhaust valves to aid starting but this "Stopping" seems very much like compression lock to me, I don't view it as a problem, I just release the starter button and re apply, that second or so allows compression to leak away a bit and the engine then spins over without problems

You can't beat a little video or three.

https://www.youtube.com/watch?v=InRVSLZMU5w

https://www.youtube.com/watch?time_cont ... e=emb_logo

https://www.youtube.com/watch?v=ECnaDXvyegw

The comments are interesting.

Easyrider5258 wrote: I sometimes have the same problem on my R1250, seems the starter turns the engine maybe  a 1/4 turn and it stops, I know there is a centrifugal de-compressor on the exhaust valves to aid starting but this "Stopping" seems very much like compression lock to me, I don't view it as a problem, I just release the starter button and re apply, that second or so allows compression to leak away a bit and the engine then spins over without problems

Yes, mine did that and I thought it was compression lock. Put it in under warranty and they replaced the battery with a larger capacity one. Hasn't done it since.

The 1200 & 1250 Wetheads share the same OEM battery and both have a compression ratio of 12.5:1.

This starting problem only appears to be on the 1250's. Surely, there has got to be more to it than just the battery.

JVB says that both the 1200's & 1250's have the same compression release too.

Wierpig wrote: Yes, mine did that and I thought it was compression lock. Put it in under warranty and they replaced the battery with a larger capacity one. Hasn't done it since.

I don't feel a problem exists "yet" with my bike ... have 2 years warranty remaining  and am keeping an eye on the starting characteristics, if it changes for the worse then it will be back to the dealer,  all my recent bikes have done it to a degree, my R1100RT & my R1200RT all could sometimes do the same, feel it's somewhat characteristic of a big twin

Hi Easy Rider et al,

Sometimes it will start when I release the starter then restart, but not all the time. There are numerous times now where it still does not start after a number of attempts. The last occasion it took 20 mins to start, that was when I returned the bike to the dealer. Interestingly they have said that they will talk to BMW Technical Services re putting a higher amperage battery on the bike, The basis of this is threefold, I have an alarm on the bike, I have a BikeTrac unit on the bike and I have a TOMTOM satnav wired into the original Sat Nav prep power. So, the Sat Nav is not powered if the ignition is off, and I do not connect the TomTom unit until after starting, the alarm and tracker should only be drawing milliamps, so I am not convinced these are the culprits. I had all these on my 1200 RT and never had any problems. We are shortly into week three of the dealer looking into this, all the while missing out on some riding!!

I had a problem with my 2014 bike.  Like you it had a tracker.  Eventually I found that the topbox interior light switch was faulty and it did not always switch off when the lid was closed and drained the battery.  I discovered it by leaving an iphone in the topbax recording. Hope you sort out the problem

My old wethead had that problem if I left it on the side stand for more than a few days, centre stand no issue

Started happening to my 2020 R1250R. Will start fine initially, ride about 30 min to my uncles. Cool 20 min Then when go to start get faulty lamp error or traction error. Use a portable jump start, it starts up no issues multiple times. But then keep happening. Took to dealer they could not replicate issue , checked codes and sent me on my way. It happened again. Dealership seem perplexed but this needs fixed. Plz more guidance?