Motor shuts down in hot temps

G/day all

Have a 2010 F800GS. bought 2 years ago new. with 63,000kms

Its summer time here in Oz, was returning from a m/c get together in Bright, (North Eastern Vic).

It was hot, 37C,(100,F) and I decided to enjoy the road before F**kW**s shut it down to 80kph (50mph) next month.

Was going fairly hard, pulled over for a roadside relief stop and a photo. Shortly after the bike suddenly died. Backed off, pulled the clutch, and the motor restarted. This got worse, (more frequent loss of power, then sudden power, not fun on a chain driven bike. )
I'm talking of at least 20kms)
Coasted downhill into Bruthern in neutral with the motor running, took on 11 lts of fuel, and Bingo, no further stop/starts back home.

My guess is that the gas/petrol was vaporising because of the extreme heat and fast riding, with a tail wind.

Anyone else experince a similar thing?

I am just guessing here, as it is hard to diagnose this, not touching the bike, but clogged pump/fuel filter, as it is harder for the pump to suck up the fuel at low levels. Add on the fact that when the fuel is low, the pump has less cooling. There have been several of your situations/symptoms..... And a a few inmates have dissected their pump, to find the filter pretty nasty.

Mine did the same thing last summer. 100*+,80 - 90 mph. Ran fine but would die and be hard to start (learned I had to cycle the key). I'm leaning towards the fuel vaporizing theory because I didn't do anything with the filter and it was fine when I wasn't running hard in hot weather. I'll be watching this thread to see what I can learn.

I have read about a similar problem in a different thread. It turned out to be the fuel pump overheating. When the bike runs low on fuel, the fuel pump is no longer fully submerged and in very hot conditions it can overheat and malfunction. When you add fuel, the pump is once again submerged and operates properly. I can't say for sure that this is what happened to you but it sounds similar.

I rode my 2012 F700GS in 47.5c ambient temp recently and it went ok so doubt it's a vaporising issue.

Cheers
Mark

My symptoms before replacing my pump & filter... Went 2 Phillip island in January in 39 degree days and 0 issues...
Bike had 65k's on....

I recon check the pump & filter

I live and ride in Mexico and my F650GS is my main transportation and daily rider. We get high humidity and high temps like you do in Australia. Since new, I have always tried to keep the tank at least half full when riding. First reason was the fuel pump cooling issue, second reason was the sound the float makes when you are moving the bike around in the garage, that knocking sound was a real WTF? moment at first, then I realized what it was. Still don't like the sound of it, though.
I have had an experience at very high elevation (4,200 meters) in sand and gravel where the yellow light came on indicating something, seemed like it was an overheat. Fan was on, temp was up a bit, and it stopped flashing when I coasted down to a lower elevation and never happened again.

Might want to look at this thread regarding my similar experience with the fuel pump.

http://www.advrider.com/forums/showthread.php?t=836460

I had similar symptoms on 5 separate occasions. 2 BMW mechanics found nothing.

After a lot of forum searching i have concluded it is the fuel pump OR fuel pump controller. BMW only sell the fuel pump assembly so I have purchased a new fuel pump from highflow fuel and fitted it. It works fine but I have not tested it on a long ride in the heat (which is when the symtoms occur).

http://www.highflowfuel.com/i-8927843-new-intank-efi-fuel-pump-bmw-f800gs-2006-2010.html

The above link i the provider- they also sell through ebay.

If this does not solve it I will try the controller

that's toasty.

After seeing a couple of fuel filters I am leaning towards they being the culprit in a lot of these fuel pump failures.

The fuel flow is dictated by the ECU in 2 ways. It controls how long the injector is held open and what pressure the pump puts out. The fuel controller does its job by increasing amperage to the pump which dictates how fast it works, ie pressure.

Put a dirty fuel filter in the mix and that has to have a bad effect somewhere trying to over come it.

How is that for non technical theory?

I don't know...Got me stumped for the moment....

Gary:

The filter being partly clogged would sure screw things up ... it would be interesting to see the specifications on the filter ... maybe our filter is crap?

If you think about the number of gallons of fuel run thru the bike's filter vs. the gallons put through an average FI automobile I sure wouldn't expect filter loading to be a problem for the average twin owner ... If I did the math, I'm sure my car's filter has run 20X more gallons through it and has no issues....

I'm not saying you're wrong ....
I'm just saying ...
well I'm just saying ...
ummmmmmmmm something seems screwy..................

Give me my

I am just going by a couple of pictures posted on this site. The filters looked pretty filthy to me and enough so to be an obstacle to push gas through. I assume that controller is going raise amperage until it gets the pressure requested, as measured at the fuel rail.

The pre filter is supposed to be 10 microns. I would expect the the post pump filter to be similar.

You don't change gas filters in your car with each oil change? My Jiffy lube guy tells me I need one.

My guy is a prince ... he lets me go with every OTHER oil change,
and since he only charge $180 + installation I'm a sport ....
Ok ... naw ... I'm not a freaking sport....

Seriously, yeah I'm with you they do look filthy ...
That's why I have the :huh on my face ... my car burns gas from the same stations and has burned lots more of it and has no issues ....
A couple years back I did change the filter on my 1986 Toyota and for grins cut the old one open ... It looked new inside........

I hate to even say it, but could the insides of our gas tanks be shedding?

I thought all of that had been covered. Fuel pumps dissolve at the sight of Ethanol and all the aluminum oxide plugs the filters.

We need the economy size filters.

Pretty good I Recon.
Chris, I had the same problems as you on my aborted trip to the OCR in August.
It got worse, to the point where the bike was basically unridable.
After faffing around for ages, I found the filter was full of shit and not replaceable.
Have a squiz at this, I think it may contain the answer to your problem
http://www.advrider.com/forums/showthread.php?t=834239

Yeah... you're right we did ...
I'm following too many threads....
It may be time to toss the Mahle and put in a Holly ... the small replaceable filter element fits better in my toolkit anyway

G/day all

I have some interesting info re my motor shutting down.
Finally got to go to my BMW shop, BM Motorcycles in Ringwood, Melbourne.
They are not a dealership, but a private BMW repair shop, IMHO one of the best in Oz.

I have just returned from NZ and this was the first time to be able to ride to Melbourne from where I live, (240kms).

Their opinion is that it is not a fuel vapourisation (sp?) in the fuel tank, but rather fuel boiling in the fuel line from the pump to the injectors creating a fuel blockage (ie air bubbles) especially after a hi speed run in very hot weather, turning the motor off, then restarting, which is exactly what happened to my bike. Solution is to run the motor flat out, to get rid of the blockages, or let it cool down.

Their reasoning/logic is
As there is no return fuel line back to the fuel tank, A, the tank can't overheat and B, the only way to flush the air pockets out is through the injectors. Hence the stop starting, farting etc, as the injectors get deprived of fuel.

Interesting.