Electrical drain?

[Comfy Old Boots]

BMW r850r 1999 abs

The problem (not a new problem) I have is the bike seems to hunt at idle. It's perfectly balanced and otherwise running great. Every time I start the bike is as follows.

I turn on the ignition and start the bike. Battery warning light on (newish battery with full power readings) and the bike will idle sweetly for as long as I want without skipping a beat.

As soon as I blip the throttle, the battery warning light goes out but the noise from the fuel pump changes and becomes laboured. It starts to vary slightly I pitch and runs a bit rough... skipping a beat every 5-10 seconds and generally being abut fluffy.

Does anyone have any ideas what could be causing this?

I thought it might be the pump itself but the pumps fine until I rev it. Clean filter, tank and clean fuel. It's frustrating because I know it shouldn't be doing this and getting a mechanic to fix this could take days of labour costs whist he's sourcing the problem.

I'm hoping someone has experienced something like this before. Any suggestions welcome. Thanks.

 

[Smug]

When the battery warning light goes out, the alternator is then charging. This then puts a load on the engine, making it tick over slower.

Could it be that the idle when charging is too slow and therefore does not sound as nice as the idle before it starts charging, which is slightly faster. If this is the case, all you have to do is turn the idle up slightly.

 

[Comfy Old Boots]

It might be. That's a good starting point smug.

It's strange though because as soon as I blip the throttle and the alternator starts to charge the battery, it really does take on a completely different character. I'll give my mechanic a call tomorrow.

Just to say though, the problem is do bad she cuts out at traffic lights on roll on...

I really hope it's something this simple. For a60,000 mile bike she's running fantastic. I'm notorious for finding faults where there are none.

Can it really be this simple?

 

[Comfy Old Boots]

No is the answer. Maybe I'm asking too much from a 14 year old bike. Character they call it?!

Might replace the fuel pump for the Audi one. Just eliminate it from the equation. Cheap at £30ish.

It's a awful nuisance at idle... Find myself riding in the 4-6000 rpm range round town for smoothness. Fuel consumption is pants as a result. Have I just been riding it wrong and need to get a brand spanking new bike to sort out fueling and fuel consumption?

 

[luke scott]

You should buy my 1150 Se then I could buy a HP2 enduro

 

[Comfy Old Boots]

You should buy my 1150 Se then I could buy a HP2 enduro

If money was like it used to be! Besides which, I'd destroy the poor girl!

 

[DrFarkoff]

Stick a Remus and a K & N on it it transforms them

Did your " mechanic" check the tps or the co values?

 

[Kritou]

No air restrictions upstream of the air filter?

 

[Comfy Old Boots]

Stick a Remus and a K & N on it it transforms them

Did your " mechanic" check the tps or the co values?

Yes by two different ones. Sold the Remus it had for it - too loud for me and it just seems to run better without it. Very happy with the work done by the way when recently serviced. Goes like the clappers! Just fluffy when idling. No panic on it it just a niggle and will get it checked more.