R1250GS 2019 Wouldnt Start

Mine already had the 16ah Yuasa battery, with 240cca
Oh boy now you are going to give me anxiety!!

I must admit this is the first post I have seen mentioning they have the same issue with this battery so interesting to know.
 
Mine already had the 16ah Yuasa battery, with 240cca
Likewise mine has the bigger Motobatt unit, still didn't stop mine from having the issues.

Mine was exactly the same symptoms: Start bike, ride four miles to mates house at start of a Euro trip, bike wouldn't restart.

Panic dash home to get OE battery and fit it. Euro trip was fine but we had no stop/start episodes, we stopped for long lunches or fuel.
 
Does anybody know how the decompressor works ?

I wonder if it is a hydraulic piston using engine oil pressure to hold the decompressor off with the engine running, making decompression its default status ready for a cold start........

Ergo if it doesn't bleed down on stopping for five minutes, the engine could be trying to crank under full compression?

Give it five minutes to do its thing and decompress the cylinders and the engine starts?

Just a thought.
 
Does anybody know how the decompressor works ?

I wonder if it is a hydraulic piston using engine oil pressure to hold the decompressor off with the engine running, making decompression its default status ready for a cold start........

Ergo if it doesn't bleed down on stopping for five minutes, the engine could be trying to crank under full compression?

Give it five minutes to do its thing and decompress the cylinders and the engine starts?

Just a thought.
The first time it happened to me I was a 5 minute walk from my house. I had nipped into the local Tesco.

I walked home, got changed and walked back with my old booster. So 20 minutes at best. Before I stuck the booster on I thought I would try and it fired up straight away. I have also read other people leaving it 30 mins and it then fires up no issues.

SO I reckon it does
 
"Both of these camshafts are driven, as before, via the chain running in the shaft behind the cylinders (on the right engine side via the balancer shaft and on the left via the crankshaft). The timing chain drives an intermediate shaft located between intake and exhaust camshaft, from which power is transmitted to the camshafts via pairs of spur gears. A decompression device controlled by centrifugal force is located at each of the exhaust camshafts. This makes starting easier. As a result the weights of the starter and the battery could be reduced."


I'm assuming the system is the similar on both 1200 & 1250 - the same symptom is heard on both.
 
Bugger, I was wondering if it could be centrifugal. That ruins that theory.

I know my old hexhead would struggle a bit to crank when hot, which I put down to piston clearances tightening up and raising compression, but it never failed to cough into life (unlike this 1250 piece of crap).
 
It would seem that the decompressor is the villain and the battery gets the blame, for having to do more than it is capable of. The battery on my Guzzi is about twice the capacity of the BMW - but it's huge and heavy and takes all the space where the BMW fancy rear suspension is, so I guess it's not an option unless I fit a sidecar...

I'll see how I get on with the new battery which I probably didn't need. Might invest in a booster before his year's trip. Bah!
 
Still haven't replaced my battery and it's never done this since.
 
Next time (if and when) mine fails to restart, I might try putting it in a tall gear and rocking it, then immediately attempt a restart.
 
Was at the dealer yesterday, to fix the SOS not working (common problem from the end of 2023).
My battery was an EXIDE, at the end of its life, new one is an original BMW East Penn. Replaced, covered by warranty. Internal resistance of the old one was 24mohm compared to the 6,5 of the new one, starting current was 110, the new one is 345. All measured with a battery tester. Strongly advice to get the tester and keep battery under control, from the first day if possible, to have a reference.
 

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I've been having simialr issues, replaced the battery with the Yuasa linked earlier in this thread in the hopes of resolving but its still occuring

Bought my 1250 GSA recently and on occasssion in stop start traffic I have stalled it, I go to restart and it attempts to turn over, fails, and brings up a Traction Control error on the dash, I go to start again and it tries momentarily again but wont start. It seems if I swith the iginition off, wait 10 ish seconds, back on again and start again its fine. But deadly embarrassing.

Differnet circumstances but the same issue, got the bike out and started it on the drive, realised I've forgotten something so tunred it off, come back ~30 seconds later and it wont start. TC error and all. Wait a while longer and its fine.

Its due in for a service in May so i will raise it with the dealer then.
 
First thing to do is a battery test. Unfortunately Voltmeter in dash is not enough to check battery health, and as you read this is a problem with no solution at the moment. A battery in GOOD condition may help. Maybe battery you bought was in bad conditions, and the seller can replace it. Better to get the heavy duty Yuasa, if you didn't.
Another trick, in short stops, leave it in Neutral gear, this could ease release cylinder pressure.
 
I've been having simialr issues, replaced the battery with the Yuasa linked earlier in this thread in the hopes of resolving but its still occuring

Bought my 1250 GSA recently and on occasssion in stop start traffic I have stalled it, I go to restart and it attempts to turn over, fails, and brings up a Traction Control error on the dash, I go to start again and it tries momentarily again but wont start. It seems if I swith the iginition off, wait 10 ish seconds, back on again and start again its fine. But deadly embarrassing.

Differnet circumstances but the same issue, got the bike out and started it on the drive, realised I've forgotten something so tunred it off, come back ~30 seconds later and it wont start. TC error and all. Wait a while longer and its fine.

Its due in for a service in May so i will raise it with the dealer then.
Get it on an Optimate!
 
I've been having simialr issues, replaced the battery with the Yuasa linked earlier in this thread in the hopes of resolving but its still occuring

Bought my 1250 GSA recently and on occasssion in stop start traffic I have stalled it, I go to restart and it attempts to turn over, fails, and brings up a Traction Control error on the dash, I go to start again and it tries momentarily again but wont start. It seems if I swith the iginition off, wait 10 ish seconds, back on again and start again its fine. But deadly embarrassing.

Differnet circumstances but the same issue, got the bike out and started it on the drive, realised I've forgotten something so tunred it off, come back ~30 seconds later and it wont start. TC error and all. Wait a while longer and its fine.

Its due in for a service in May so i will raise it with the dealer then.
Did you get the higher capacity battery as there are two versions??

It has the high cranking amps
 
Yeah I got the higher capacity Yuasa. Its on an Oxford trickle charger in the garage when not in use so voltage isnt the issue. It's the same problem on two batteries so I feel its unlikely to be the culprit.
 
Yeah I got the higher capacity Yuasa. Its on an Oxford trickle charger in the garage when not in use so voltage isnt the issue. It's the same problem on two batteries so I feel its unlikely to be the culprit.
Yeah defo sounds like you have other issues going off here

I have to admit once I replaced my battery its been, touch wood, fine

SO I hope you do get it sorted
 
Mine already had the 16ah Yuasa battery, with 240cca
Gave up this week with the higher amp Yuasa I fitted - followed (I think) Bigcat and fitted a hybrid Motobatt version. The Yuasa was beginning to struggle turning over the engine - even when straight off charge. The Yuasa never showed more than 12.7v off charge.

Now, off charge, it shows 13.4v, even after a short run.

It could be that the Yuasa had sulphated as I do many short journeys - I now keep an eye on the voltage on a regular basis.

If anyone wants an FOC battery that may be recoverable (collect only), pls drop me a pm.
 
over year later still using the optimate on the battery. Shes never done this again. I think it comes down to battery health entirely. As long as you use a good charger and are religious about the bike being plugged in then the battery will remain in good condition (within reasonable lifetime deterriation)
 
The main issue is that this engine requires a big amount of Amps in some conditions, due to its compression, mostly when restarted after a short stop.

Apart from the battery itself, this problem can be exhacerbated by some technical problems in some parts like:
- valve clearances
- starting motor in bad conditions
- cables between battery and starting motor with bad contacts
- a problem in starting relay

All these factors work together, and some people report that also a new battery does not completely solve the problem, others have more luck.

In this game, only a battery in PERFECT conditions can help, and once it gets a little old and loses some of its power, we have our BIG problem.

The culprit? Probably BMW could have planned a bigger battery, with that we would have had more reserve.
I also see from forum posts that many batteries are prone to die in short terms like one or two years, but seen that this sh*t happens with all batteries, OEM or not, difficult to say if there is a general path of lower battery standards.

At the moment the only real solutions seems a frequent battery check (and change when needed) and to have a car jump starter in the toolbox. To have all the other things in perfect condition can help, but often it's not easy to check them. A battery tender can help, but sometimes if it does not work well can also kill the battery and, again, it's not easy to know if the battery optimizer is a masked killer ;-)

Seen that BMW has no intersest to solve the problem, our only way is to get the better battery we can, but it's not easy. Lithium could be a solution, but we should get a battery that uses ALL the space to have a battery well overdimensioned, like the Antigravity 12-24 that in the specs could seem like a good option. But then the question is if the battery will last enough to compensate the higher costs.
 
The main issue is that this engine requires a big amount of Amps in some conditions, due to its compression, mostly when restarted after a short stop.

Apart from the battery itself, this problem can be exhacerbated by some technical problems in some parts like:
- valve clearances
- starting motor in bad conditions
- cables between battery and starting motor with bad contacts
- a problem in starting relay

All these factors work together, and some people report that also a new battery does not completely solve the problem, others have more luck.

In this game, only a battery in PERFECT conditions can help, and once it gets a little old and loses some of its power, we have our BIG problem.

The culprit? Probably BMW could have planned a bigger battery, with that we would have had more reserve.
I also see from forum posts that many batteries are prone to die in short terms like one or two years, but seen that this sh*t happens with all batteries, OEM or not, difficult to say if there is a general path of lower battery standards.

At the moment the only real solutions seems a frequent battery check (and change when needed) and to have a car jump starter in the toolbox. To have all the other things in perfect condition can help, but often it's not easy to check them. A battery tender can help, but sometimes if it does not work well can also kill the battery and, again, it's not easy to know if the battery optimizer is a masked killer ;-)

Seen that BMW has no intersest to solve the problem, our only way is to get the better battery we can, but it's not easy. Lithium could be a solution, but we should get a battery that uses ALL the space to have a battery well overdimensioned, like the Antigravity 12-24 that in the specs could seem like a good option. But then the question is if the battery will last enough to compensate the higher costs.
I don't see how an optimiser that mimics normal charging from running the bike regularly is a silent killer. That makes no sense.

From all the bikes I've marshalled from any brand over the years it's the commuters that lasted the longest without issues. Regular use being key. A good battery charger mimics the charge state of regular riding. If you dont have one. Get one.
 


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