Misfire - fuelling issue 2008 F650GS 800

[CV35Ian]

Hi
Fixed ignition module problem in December,, not used bike since as road round here have been either icy or mud slicks.

Anyway went for a spin yesterday, all fine so decided to use bike for work today - 26 miles on A and B roads. After about 10 miles bike hesitated on acceleration then was OK, another 5 miles later it hesitated again going round roundabout - last few miles it was alternately OK and then hesitated when opening throttle, fuel starvation?

Did stop to top tank up with new fuel after 20 miles in case gauge wrong (only got 4,.5 litres in) so wasn't low - didn't really help. Did notice that the range to empty started at 106m then was at 118m after 20 miles when I pulled into petrol station.

So thoughts, could it just be needing fuel filter? Is that an easy job? Or could it be electrical - is there a diagnostic port on these, if so where? All help appreciated.

Will be extra careful on way home tonight.

Thanks

 

[OldCroc]

Firstly if the bike has been stood for a while it could be some condensation in the fuel. I would keep riding as it may clear itself. (Just be ready to grab the clutch in the event of a stall on a roundabout ! ).
There is a round diagnostics plug under the seat. You need a suitable cable with the round on one end and the standard OBD on the other and suitable software such as Motoscan to read any faults.

 

[CV35Ian]

Thanks, did wonder if it could be that, or even faulty/damp coil packs - need to check my Haynes manual to see where they are!!!
Annoying, it’s the second issue I’ve had on the bike.

 

[squibb34]

I'm thinking fuel tank breather, or maybe the fuel pump &/or controller - have a browse through the common issues in the 'Bikes' section.

 

[CV35Ian]

Thanks all, i'm thinking if coil packs faulty it would throw up an EML warning - just like my wife's hyundai did, 4 could packs later (only £80 aftermarket) and all sorted.

Will google fuel pump controller as well, need to find that and breather pipe to check.

Used to Boxer twins so all a bit new to me, presume false tank cover off to get to coil packs, plugs and pump/filter.

 

[CV35Ian]

Ok so trip home was exciting, fine for 10 miles then slight hesitation, then red ABS light came on then orange triangle warning then felt really down on power and lights a bit dim, was looking for somewhere to stop and dash went dark and I pulled over - enough power to run hazards but nowt else.
Called RAC, oops when I transferred insurance from Transalp I forgot to transfer recovery - frantic calls ensued and I found a fab chap in Leamington who was there in 20 mins , loaded bike up and dropped me and bike home just over an hour after I first called £100 I didnt begrudge.
I’m thinking ignition module problem may have killed the new battery? Will try that first and make sure it’s charging ok.

 

[CV35Ian]

Ok battery at 12v ignition on, drops to 10 when starting but then stays around 12.5v when running.
Could that still be battery or charging circuit
Thanks

 

[SteveT]

When running, the bikes electrical system should be kicking out 14.5V, so I'd say that you need to check both the regulator/rectifier and the out put from the stator.
Fried stators on the 1st version of this bike are a known weak point, sorted on the 2nd version with a revised stator that is able to be used on the first models.

SteveT

 

[CV35Ian]

When running, the bikes electrical system should be kicking out 14.5V, so I'd say that you need to check both the regulator/rectifier and the out put from the stator.
Fried stators on the 1st version of this bike are a known weak point, sorted on the 2nd version with a revised stator that is able to be used on the first models.

SteveT

Thanks, Haynes Manual was bed time reading last night. Replacement of parts easy but not sure how to test each bit separately like I did on car (ie test output volts) on alternator - is using multimeter with prong type leads on alternator plug ok to do - presumably id need stator cover off? Or is it simpler for £100 to replace both stator and regulator?

 

[seahorse]

Revised stator is vented and I think was from 2013 so yours probably the old type. I had the same on a 2012 bike and had to replace that and the reg/rec.

 

[CV35Ian]

Revised stator is vented and I think was from 2013 so yours probably the old type. I had the same on a 2012 bike and had to replace that and the reg/rec.

Thanks, will do

 

[SteveT]

No need to remove the stator cover. To test the stators output, find the 3 yellow leads coming out of the cover on the right hand side. Open up the plug connector that those 3 wires lead to and with the engine running, check for the output voltages against values stated in the Haynes manual.

As mentioned, the later stators fit the older bikes.

I'm running a 2012 bike with the 1st version engine and a 2014 with the revised stator set up. 2014 bike has been mine for nearly 6 years and 26k miles without bother. The 2012 bike has been mine for just 8 months but had a neglectful keeper before me, but its fine.

Hope you get your sorted and can ride some stress free miles on it soon

SteveT

 

[OnHellas]

Revised stator is vented and I think was from 2013 so yours probably the old type. I had the same on a 2012 bike and had to replace that and the reg/rec.

I think that it was the flywheel from the later bikes that was vented.
The updated parts being from the 2013 year model onwards.

My ‘09 bike was updated at around 68,000 miles after trying two stator rewinds.
It stayed 100% reliable up until 126,000 miles when I sold the bike.

 

[seahorse]

I think that it was the flywheel from the later bikes that was vented.
The updated parts being from the 2013 year model onwards.

My ‘09 bike was updated at around 68,000 miles after trying two stator rewinds.
It stayed 100% reliable up until 126,000 miles when I sold the bike.

You're right yes wasn't thinking

 

[OnHellas]

You're right yes wasn't thinking

It’s the thinking that normally gets me in trouble!

 

[RadioFlyer]

When the stator fails it will almost always be a case of a coil shorting to ground which is easily checked. There should be no continuity to ground on any of the three yellow wires coming from the stator. In lieu of the grossly overpriced new vented flywheel replace the shunt type R/R with a series type which will result in the stator running cooler.

Does you bike have the silver coloured fuel pump controller? They are prone to failure. Get a newer black one.

Run some fuel system cleaner through.

 

[CV35Ian]

Thanks all
Replaced stator - £65 aftermarket and now charging nicely. Might replace voltage regulator as well just in case when the UK supplied part arrives from not UK apparently

 

[frosti]

Thanks all
Replaced stator - £65 aftermarket and now charging nicely. Might replace voltage regulator as well just in case when the UK supplied part arrives from not UK apparently

Use a good gasket, mine leaked a lot after fitting the new stator and I ended up buying a BMW supplied gasket to fix it

 

[CV35Ian]

Thanks
I did clean both crankcase and stator cover surfaces before replacing gasket. I used an Athena one - £26.

 

[CV35Ian]

OK so I did replace the stator and voltage regulator, battery at 12.8v standing and about 14.5v charging
HOWEVER
Took bike out this morning and all great until about 10 miles again, misfire/coughing. Turned round and got back home OK.
So whats next - I'd really like to diagnose this properly before forking out on replacements parts - bike, apart from this is a keeper, really like it.
If I get a Unicar Scan plus Motoscan - c £80 will that be able to see any faults on either the coils or fuel pump and controller. I'm thinking if Coils, EML light will come on so do we think Fuel pump, Filter and controller are best replaced first and dont bother with Scanner etc?
My commute is 26 miles each way so really need to trust bike to get there and back.
Thanks