BMW K75c, will start and run for few minutes than dies and won't start at all

[Krompus]

Hello Gentlemen,

I am so thankful that I got to make an account on this extraordinary community.
I just bought few days ago a K75c-1992, the other owner told me that she has some electrical problems but I didn't considered. I just want it! Anyhow, the problem with the bike is that after it sits like a day, i pull the choke and it'll start without problem, but after few minutes will die and when i want to start it again, it has no juice in the battery. As well I noticed that after she dies if i open the fuel tank cap it will make a sound like opening a bottle of soda-is that normal?
If some of you guys had the same problem and you have a simple and cheap solving for this problem please advise.
Thank you folks!

Best regards,

[johnny]

greetings krompus...

how do you getts it to turnover with no juice in the battery...

jumper cables battery tender battery charger other...

j o

[Krompus]

Initially when I start it seems that it has power, after few minutes dies, and I can hear the starting relay clicking and the engine is not spinning (like there is no electricity in the battery). When I said Juice in the previous post I was making reference at electric power in the battery. The battery is one of those you can't add up acid or distilled water. Any suggestions?

[The Dude]

Hello Krompus,welcome.
My K75 has not had these problems.Regularly ridden with 250,000km.You will need to provide a lot more info for a quick diagnosis.
There is a massive archive of info here which will help.
Because you describe no juice in the battery,best buy a new one or at least make sure that the original one is not working properly.The battery should give hundreds of starts before no juice left.
The soda pop on opening the fuel tank cap is not usual.
You should try some basic eliminations,for instance:
Good batery.
Charge light extinguishes?
Open tank cap,and repeat start test.Listen for fuel pump noise,watch for any odd flow, bubble etc in the tank.
Understand any current leakage with an amp meter.
Try squirting engine easy start around the throttle air tubes.these can leak when old.
The point is these things are logical,just need good info from you for best results.Take the time to read the site info and understand how these motors work will be a good investment.once you have sorted this problem out and given the machine a good overhaul,you will have trouble free motoring for many years.
Cheers,

[John Lang]

Might the tank vent be blocked so that air cannot replace consumed fuel?

[johnny]

greetings krompus...

why did you dance around my question without answering it...

if you want my help you will have to answer my questions...

so... answer my question in my above post and include voltage before turning key on... voltage key on start button pushed... voltage engine running... and voltage  when it dies...

and post a photo of your fuel filler hole with the cap open showing the entire filler hole with open cap looking into the tank...

j o

[Laitch]

Hello Gentlemen,
I am so thankful that I got to make an account on this extraordinary community.

Answering johnny's query is the first thing for you to do on your list.

Secondly, MOTOBRICK.COM's membership is comprised of all five recognized genders. In fact, it's likely some of its members change genders according to tide tables, certain days of the week or the color layout in their sock drawers, so greeting us with "Gentlemen" might be considered insensitive. Use, Comrades, Buds, Your Holinesses or something else gender neutral.

Thirdly, your thankfulness may start waning because you've picked an inauspicious time to ignore the wealth of No Start information supplied on the very page that you've posted. In the spirit of brother/sister/otherhood, I'll suggest that after you've answered johnny's reasonable request by attaching a voltimeter or multimeter to the battery at the intervals suggested to determine its output, respond with the results here. If the battery actually is good, return to the No Start main page and carefully perform No Start maintenance procedures 1, 2 and 3 highlighted at the top of the page and get back to us with the results. It won't cost you a penny.

The soda pop sound isn't worth thinking about right now.

[Krompus]

greetings krompus...

why did you dance around my question without answering it...

if you want my help you will have to answer my questions...

so... answer my question in my above post and include voltage before turning key on... voltage key on start button pushed... voltage engine running... and voltage  when it dies...

and post a photo of your fuel filler hole with the cap open showing the entire filler hole with open cap looking into the tank...

j o

J O, I will do what you have said tomorrow, and I will take pictures and post them in here. Thanks for your help!

[Krompus]

Hello Krompus,welcome.
My K75 has not had these problems.Regularly ridden with 250,000km.You will need to provide a lot more info for a quick diagnosis.
There is a massive archive of info here which will help.
Because you describe no juice in the battery,best buy a new one or at least make sure that the original one is not working properly.The battery should give hundreds of starts before no juice left.
The soda pop on opening the fuel tank cap is not usual.
You should try some basic eliminations,for instance:
Good batery.
Charge light extinguishes?
Open tank cap,and repeat start test.Listen for fuel pump noise,watch for any odd flow, bubble etc in the tank.
Understand any current leakage with an amp meter.
Try squirting engine easy start around the throttle air tubes.these can leak when old.
The point is these things are logical,just need good info from you for best results.Take the time to read the site info and understand how these motors work will be a good investment.once you have sorted this problem out and given the machine a good overhaul,you will have trouble free motoring for many years.
Queers,

Dude,

Thanks a lot for the hints, I will start reading the literature and as well do what johnny said, and i will come with updates. I appreciate you involvement.

[TrueAce]

Welcome , Krompus. Take one problem at a time. My guess is your battery need replacing, check with a voltmeter for 12.8v. If it will not handle more than a single crank, and all connections are secure, then your battery may be failing.

[Martin]

Bricks are very battery sensitive a bad or low battery could result in the starter relay welding it's points closed. And you don't want that to happen, check your battery. Welcome to the world of the Brick from the land of OZ.