"Hard" Starting

Got a bit of an odd issue with the new to me 04' GSA. The thing can range from fine to total PITA to start, it doesn't seem to follow any pattern. It can start great cold and take 15 cranks when it's warmed up. Yesterday morning, following a night out in the downpour up in the Catskills, it took a long time, almost killing the battery. Got it home, let it sit for about 30 min, then went to bring it to the garage, same deal. It's been this way since I got it, but has been worse lately. Although I've not done any investigations towards this issue, I've independently seen 1. nice brown plugs that don't indicate any spark weirdness 2. a clean air filter with no obstructions and 3. a fuel system that is delivering gas just fine cause one of my quick disconnects broke on the way home from Bloomsburg, soaking me and the transmission in gas for a good 100 miles before I noticed it.

While at Bloomsburg, another strange incident occurred. I had been putzing around the grounds and stopped to check in on the GS Giant thing. Stayed about 40 min then went to start the bike. Granted it was about 230 degrees F outside, but after about 10-15 jabs at the starter BANG, the left fuel injector was blown off and the spark plug wire disconnected and sent the plastic cover on the valve cover flying. Pulled out the tool box, reattached the tb, plugged the spark plug wire back into the end that was still attached to the plug, turned it over and it purred just fine, like nothing had happened. The loud noise sure did attract a bunch of shade tree mechanics though.

What did they think ?

Not a whole lot, was one of them you?

I'd consider getting the injectors serviced. Maybe something is clogging them? Back pressure would be the result and might explain the sudden exit you witnessed.

Ethanol Problems?

Ever since the US switched over to mostly E10 I've noticed issues on many cars and motorcycles. Asking family and friends, they too noticed that their vehicles hard start more often or take longer to turn over. Smaller displacement engines seem to have more trouble than larger in my experience.

I had a problem on my F800ST for a while, but after several bottles of Techron and watching the stations I go to, it hasn't happened since. I noticed it mostly when I ran the bike for a while so it was hot, let it sit 5min to an hour, and then try starting it again. Evaporating ethanol leaves a varnish that can clog injectors, which seems to align with my observations.

I've seen reports of people testing gas from various stations (I haven't tried this so take it with a gain of salt) and while the average is suppose to be 10% (E10), any particular fill up at a station can be much higher. Apparently 15-25% isn't unheard of.

Get some Techron, pick a single, high quality fuel station (I prefer Shell and Chevron, YMMV) and see if that changes anything. It did for me and I suspect that I had gotten a couple of >E10 ethanol fill ups (given how random/intermittent it was).

Just a thought.

I seriously doubt ethanol is your problem. The bikes an '04 so it was built to run on some mixture of ethanol.
First thing I would check is the fuel line connectors. If one popped off, it or anohter could be loose letting the system loose pressure. Also check the HES wires, then check the O2 sensor and see if it's working correctly.

hard starting and one substantial backfire

I'd tend to start with compression and valve lash and then consider the HES after that.

Which flavor of "nice brown plugs" do you have. Take a look at the linked chart.
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp

rxcrider said:

hard starting and one substantial backfire

I'd tend to start with compression and valve lash and then consider the HES after that.

Which flavor of "nice brown plugs" do you have. Take a look at the linked chart.
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp

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I was leaning towards a compression issue of some sort, although that seems out of place on a bike with low miles and gentle use. Did I have this issue before the last time I did a valve adjustment..........I don't think so, but I only owned it for about 300 miles before the valve adjustment. The left head (the one the tb popped off of) is awfully "tappy", so I possibly set something loose, but I cant imagine it'd be that loose.

more investigation is needed.

jduke said:

I seriously doubt ethanol is your problem. The bikes an '04 so it was built to run on some mixture of ethanol.
First thing I would check is the fuel line connectors. If one popped off, it or anohter could be loose letting the system loose pressure. Also check the HES wires, then check the O2 sensor and see if it's working correctly.

Click to expand...

Have to agree on the ethanol. At some point the motor manufacturers out there must have noticed the ethanol destroys certain materials in the fuel system and fixed it.

But how exactly does one check the O2 sensor? I've heard this suggestion before but never how to do it so I am curious.

gunderwood said:

Get some Techron, pick a single, high quality fuel station (I prefer Shell and Chevron, YMMV) and see if that changes anything. It did for me and I suspect that I had gotten a couple of >E10 ethanol fill ups (given how random/intermittent it was).

Just a thought.

Click to expand...

Once varnish has formed inside the injectors, I do not believe any amount of Techron will remove it. I ran three bottles of that stuff through a bike that mostly sat on a 4000 mile ride and when I got home I had the injectors professionally cleaned.
That is what fixed them. The 2 bottles of Techron were a waste of money.

I think the stuff is great for maintenance but not for repair.

156327 said:

Have to agree on the ethanol. At some point the motor manufacturers out there must have noticed the ethanol destroys certain materials in the fuel system and fixed it.

But how exactly does one check the O2 sensor? I've heard this suggestion before but never how to do it so I am curious.

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Not necessary. The Germans are famous for engineering things which only work well in Germany. Case in point, German A/C's. They don't use them much and thus optimize for lightweight and small...which causes all kinds of problems in the hotter parts of the US.


Also, the Auto Alliance filed a lawsuit against the EPA because of E15 and BMW publicly said E15 was a problem for them today and they wanted at least 5 years of study. The astute will note that only E10 is used here, but as I said, that's just an average and there are well known properties of ethanol which lead to increased water absorption and separation (i.e. ethanol is more soluble in water than hydrocarbons) so that any particular fill up can be well in excess of 10%. Again, 15-25% ethanol levels in actual fuel tanks on vehicles with failed injectors/fuel pumps/etc. is not uncommon (BMW claimed their dealers were seeing something like 18%).


It doesn't take much googling to notice that there have been a rash of fuel system failures (above and beyond "normal"), particularly on high performance vehicles.

That's not to say the OP should check everything else to make sure it's not another problem. However, don't be surprised if you can't find anything wrong and the problem goes away on it's own after watching where you fill up/Techron/replace X part in the fuel system (commonly the injectors).

156327 said:

Once varnish has formed inside the injectors, I do not believe any amount of Techron will remove it. I ran three bottles of that stuff through a bike that mostly sat on a 4000 mile ride and when I got home I had the injectors professionally cleaned.
That is what fixed them. The 2 bottles of Techron were a waste of money.

I think the stuff is great for maintenance but not for repair.

Click to expand...

Obviously YMMV. In my experience and research, Techron works for smalls amounts of varnish (kind of like seafoam with regular gasoline varnish...for small amounts it works, but at some point you have to dissemble/clean/replace), but won't fix your injectors if you got a tank with an ethanol content >>10% as it likely dissolved some of the fuel system.

If you got a cylinder of unburnt/incompletely burnt fuel, the ethanol varnish loves to mess with the O2 sensor. That seems to be a likely cause of vehicles which are running fine, get shut off and then won't start <1hr later. It's infuriating to stop by home to grab lunch or something to drink and then the bike won't start again unless you crank on it again and again. Once it starts, it runs fine...check everything and nothing appears to be wrong.

The shop that cleaned my injectors found reduced flow rate in both most likely due to varnish deposits. And I say most likely because they also told me these particular injectors cannot be disassembled. The only replaceable parts are the inlet filter baskets and the outer O Ring.

They put them on a fancy hi pressure rig that measures flow rate while shooting the cleaner fluid through them. What it is I don't know but it ain't Techron, that's for sure. My guess is some heavy duty solvent that dissolves any deposits and the pressure does the rest.

There was another thread here recently where a fellow posted a nice charted result of his injectors before and after state when they were professionally cleaned. Quite remarkable.

Source

gunderwood said:

Not necessary. The Germans are famous for engineering things which only work well in Germany. Case in point, German A/C's. They don't use them much and thus optimize for lightweight and small...which causes all kinds of problems in the hotter parts of the US.


Also, the Auto Alliance filed a lawsuit against the EPA because of E15 and BMW publicly said E15 was a problem for them today and they wanted at least 5 years of study. The astute will note that only E10 is used here, but as I said, that's just an average and there are well known properties of ethanol which lead to increased water absorption and separation (i.e. ethanol is more soluble in water than hydrocarbons) so that any particular fill up can be well in excess of 10%. Again, 15-25% ethanol levels in actual fuel tanks on vehicles with failed injectors/fuel pumps/etc. is not uncommon (BMW claimed their dealers were seeing something like 18%).


It doesn't take much googling to notice that there have been a rash of fuel system failures (above and beyond "normal"), particularly on high performance vehicles.

That's not to say the OP should check everything else to make sure it's not another problem. However, don't be surprised if you can't find anything wrong and the problem goes away on it's own after watching where you fill up/Techron/replace X part in the fuel system (commonly the injectors).

Click to expand...

Here's the source:

Bimmer Magazine said:

The lawsuit filed by the Alliance of Automobile Manufacturers against the EPA's decision to allow E15 was just seconded by another lawsuit against the plan, this one from the National Petrochemical and Refiners Association.

Ethanol causes premature fuel pump failers, premature fuel filter clogging and carburator problems with small engines. It is also causing fuel injector problems on some BMW engines like the M20 that never had fuel injector issues prior to the introduction of ethanol in fuel.

BMW North America spokesperson Matthew Russell said "E15 is a problem for us, and further testing needs to be done. We advise our customers to check their owners manual. Instead of incremental steps to increase the content of ethanol in gasoline beyond E15, the BMW Group supports an approach with sufficient lead time (minimum five years) in moving forward." As an aside, BMW dealers routinely test "E10" to find ethanol concentrations up to 18%.

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gunderwood said:

Obviously YMMV. In my experience and research, Techron works for smalls amounts of varnish (kind of like seafoam with regular gasoline varnish...for small amounts it works, but at some point you have to dissemble/clean/replace), but won't fix your injectors if you got a tank with an ethanol content >>10% as it likely dissolved some of the fuel system.

If you got a cylinder of unburnt/incompletely burnt fuel, the ethanol varnish loves to mess with the O2 sensor. That seems to be a likely cause of vehicles which are running fine, get shut off and then won't start <1hr later. It's infuriating to stop by home to grab lunch or something to drink and then the bike won't start again unless you crank on it again and again. Once it starts, it runs fine...check everything and nothing appears to be wrong.

Click to expand...

Boy, does THAT sound familiar! I've been having starting problems with my 1150RT since spring, and the dealer can't find anything wrong. That same thing happened to me again last week on a bike trip up north. I was off the bike about an hour, and it took me 5 minutes to get it started again. Earlier in the trip I had stopped for coffee, was off the bike about 20 minutes, and it started just fine. Makes no sense. Of course, no error codes found and the bike ran like a top.

While it may not be the problem, I'm having my injectors checked right now to see if they need cleaning up, along with checking for a bad wire.