BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

I spoke this past Sunday about how well my bike was running after a throttle body synch and valve job, and a seafoam treatment. For a day or so at least my '02 R1150R was a champ.

Last night I went for a ride and it seemed - and I may have imagined it - that it was running a little rough at idle. Well, no, I wasn't making it up, it was, just a little.

Tonight, as I can never stop tinkering, I took the bike apart to install a new power supply for my Garmin GPS. The last power supply was quite a bodge job, and I got a keen barewire one to put in. Basically, to do so, I removed the tank. That means fuel lines, fuel tank vent lines, and fuel pump power. I installed the barewire GPS power using the heated grips circuit, and used a ground from the white what looks like a relay-mounting-position-without-a-relay in the fusebox. That all seems to have gone fine.

When I put it all together, I found that the bike was running on the left cylinder only. Does not seem to matter what RPM, there's just nothing going on at all on the right side. The bike will not stay running, and when you rev it, it backfires loudly ( which I kinda like, but that's beside the point).

Any hints as to where to start to diagnose the problem, other than taking it to the dealer?

Thanks in advance for you help. I am supposed to go for a 4 day ride this Canadian Long weekend!

Ritchard

I have always heard to check the right side throttle cable whenever you remove the tank. Make sure it is seated into the housing where you do the adjustment for TB sync.

I did check the right throttle, I even operated it manually and nothing at all happened. That right hand cylinder is totally dead. I also removed the sparkplug just 'cuz, and found it to look perfect.

I just don't know what to do next.

Hm. Right sparkplug looks good, though it's not running. Must be no fuel getting to the right side, otherwise the plug would be wet. I'd be checking the right-side fuel injector electrics.

What sort of check can I do on the injector electrics?

Well, I'm off into theory-land, now, never having done it, but I believe you can pull the fuel-injector from the throttle body, crank the engine and see if the fuel is spraying from the tip OK. Use a paper coffee cup or something over the injector to avoid getting gas all over everything. If the injector isn't ticking and spraying, look for a disconnected trigger wire.

Maybe somebody who has actually done it will chime in.

I'm not much help either when it comes to electrical stuff, but you apparently put something back together incorrectly.

I would take it all apart and start over, maybe find a different ground connection, then systematically re-install the tank, etc. making sure all connections are correct and secure. Its most likely something simple, like switched vent hoses or something. Maybe the fuel pump connector is not together good. Check it all out again.

What I learned this morning is that my judgment is not all that great later in the evening after a long day at work.

I got up early to fiddle with the bike before work today. I felt pretty sure it was a fuel injector issue, so took out both injectors and shot them into a cup. Both were working fine. A good and bad result, I guess, as I didn't really know where to look next. When I was looking carefully at the right side injector, I noticed the simplest problem. And you're all going to groan at me here. The throttle cable sheath was dislodged from where it meets the TB adjustment. I pop it back in, the bike runs like a champ again. I had read a lot later last night and this morning about how the two sides have to be right in synch, but couldn't imagine something so simple being so critical.

After a long day at work, working in my dim garage, tired out, I simply could not see the problem. I got so frustrated that I went shopping online for another bike so that I would have something to ride for this trip this weekend. I should just calm down, and maybe not drink so much coffee.

All that having been said, I am unbelievably relieved. Thank you for your advice.

Ritchard

The post immediately below your original post, by dgates, made mention of the potential problem !!!!!

boxermania wrote:Ritchard

The post immediately below your original post, by dgates, made mention of the potential problem !!!!!

Yes he does! That would have been the first thing I would have thought of too......

This culprit was originally discovered by CycleRob. Several years ago, I made a thread about my bike running rough after a battery change and nobody could figure it out. CycleRob then came to the rescue. He actually stared at his Roadster in the garage to see what could actually go wrong during a tank removal. He asked me to check the seating of the right side throttle cable as it looked to him as it was something that could get disloged from a tank removal/reinstall. Sure enough that was the problem. Everyone was impressed with CycleRob's diagnostic skills.

That does seem to be a common problem, it happened to me once after a tune up, I was lucky enough to have spotted it right away and it didn't confound me for long. now I always make sure that cable is set right.
Don

boxermania wrote:Ritchard

The post immediately below your original post, by dgates, made mention of the potential problem !!!!!

You couldn't be more right. It was later in the evening, I was tired and it was getting quite dim in my garage. I thought I checked, but clearly not nearly thoroughly enough. And admittedly, in my stubborn/obsessive way, I had already decided it must be something more sinister.

I am slightly embarrassed. Shame on me, I asked for help, got it, and did not pay sufficient attention.

+! to dgates for hitting the nail on the head.

Don't feel bad. My bro and I have been messing with hotrods for 15 years and we had bought an old style points car and got it to fire up once. That once burned up the coil. The guy we got it from did not put a resistor in the car. No prob. Put in a resistor and could not get it to start. Bought a new coil, new points, a condensor, checked all the plug wires, nothing. In a fit of desperation my brother traced back the wires to the distributor planning on running all new wire. That is when he found the blown fuse. 3 days of effort for a blown fuse and 2 people banging on it.

We forgot the first rule. Look for the stupid obvious first.


Glad to hear you bike is back.

Dan...

The right side TB cable from the junction box is a little too short and easily gets pulled out of the adjuster ferrule when you are wrestling with the fuel QD's or the fueltank. The right cylinder goes dead, even if you manually open the right throttle shaft's pulley with your fingers because the left TB shaft has the TPS on it. Since the left TB is on the idle stop, the TPS is "ordering" idle mixture. If you open just the right throttle, in reality, even more than the popped out cable is already holding it, it still will not run because the idle speed fuel injected is way too lean to fire. Dead right cylinder no matter what.

With the engine running, you should never manually open only the left TB throttle butterfly by itself. That will cause a huge excess amount of fuel to be injected in the right cylinder. That's my "don't eat the daisies" warning.

Anytime the fueltank is removed, the 1st thing to check before you start the engine should be that the right throttle cable is centered and seated inside it's adjuster ferrule. When it is centered and buried, turning the throttle to the full throttle stop will seat it home where it belongs. Now you can start the engine like you usually do.

.

That's putting it very succinctly, CycleRob.

I am still quite astonished at the effect that this seemingly tiny amount of cable misalignment caused. At least I am learning something through all this.

R

Remow2112, Something else I learned about the coil power circuit you described was learned in reading a service manual schematic before any damage was done. The ballast resister needed sometimes has TWO resistors built in it. One has a lower Ohm value powered by when the key goes to "start", the starter is cranking the engine and dragging the battery voltage way down to ~11 V. That gives a nice strong spark for starting in sub zero weather when the battery is at it's worst. The second one with more resistance, continues to protect the coil AFTER the engine starts, you let the key return to "run" position and the alternator brings the system voltage to ~14.2V. If you only hook up a single "run" resistor, the engine won't start very well . . . most of the time -and- you'll have an "extra" (start) wire that isn't connected.
Newer systems used coils with built in resistors and needed just the single "run" ballast resistor, since the "start" wire from the starter hooked (with blocking diode) to the coil (+).
Even back in the days of breaker points, you needed to know what you were doing.

.

Oilhead wrote: This culprit was originally discovered by CycleRob. Several years ago, I made a thread about my bike running rough after a battery change and nobody could figure it out. CycleRob then came to the rescue. He actually stared at his Roadster in the garage to see what could actually go wrong during a tank removal. He asked me to check the seating of the right side throttle cable as it looked to him as it was something that could get disloged from a tank removal/reinstall. Sure enough that was the problem. Everyone was impressed with CycleRob's diagnostic skills.

I just had this happen to me. I'd had the tank off all winter, as I was waiting for quick disconnects and fuel line to come and it got too cold to work out there. Well, it's warmed up so I finally finished the job and the right cylinder wasn't running at all. Looked and didn't find this thread, but did read about seafoam so I put some in and rode it. Bad move! Catalytic converter was glowing from all the unburnt fuel!!! So don't do that to your bike.

It was as written above, the right throttle sleeve came up and was displaced/snagged on it's holder not seated down in it as it should be. The throttle could never close on its stop. It was a simple fix, but had to be noticed first.

I hope others find this thread and don't overbake their catalytic converter.