"Slow" starting issue

[bosnjo]

This issue has been largely discussed on this and on US forum.
It's all about the battery problems from the factory or the replacements that are not strong enough.
The problem occurs when cams stop on the highest compression position when you turn the engine off. In that case, the starting procedure needs a lot of CCA power from the battery. That is the reason it sometimes happens, sometimes it doesn't. It all depends on the cams position.

So, after a lot of posts, the conclusion is, the best battery cost wise:
Yuasa YTX14H-BS - 240 CCA
Dimensions: 150mm x 87mm x 145mm
1.2A, CCA 240A, 12Ah

 

[peej1977]

Thanks all, I am aware of the "bad batch" issue which my 2019 suffered from but I'd been assured this wasn't present on the latest bikes. It defo feels like the battery isn't strong enough, but it pains me to replace it myself especially when BMW won't acknowledge there is an issue.

 

[siddo]

Anyone tried upgrading their power cables?

Starting upgrade kit

Starting upgrade kit available from Motorworks, the UKs number 1 for BMW motorcycle parts

www.motorworks.co.uk

 

[Bigcats]

Oddly this has just happened on mine for the second time in a year.

2019 still on original battery....regularly put it on a CTEK maintainer (not always though). Went for a run Sunday and zero issues.
Went to work on it this morning and it did that funny slow start and popped up a warning message (should have known then) but started.

14 miles motorway blast to work....

Started fine when I left work....13 miles home, stopped at Tesco and wouldn't start, threw up loads of errors. Left it for 30 mins and started.
Now ordered a Yuasa YTX-14H-BS 240cc but not getting here till Tuesday.
Very annoying.

 

[Engineer]

Mine started to do this about 6 months after buying the bike - if the battery is slightly low it is almost guaranteed to do it - my tracker tends to deplete the battery enough after 3 days without use and then it is pot luck as to whether or not it will start. My dealer says the battery is OK. I now keep the bike on the BMW charger when not in use, although sometimes I cannot avoid leaving it for a few days.

When I first turn on the bike, I monitor the battery voltage on the display and wait for it to climb as far as it is going to before starting the bike - if I try to start the bike when it is around 11.6 volts the problem happens - if the voltage is too low the engine will hesitate 'kick back' with a splutter and an engine fault will be reported. BMW know what the issue is but have yet failed to acknowledge it.

P.S. my bike is a 2021 R1250 GS