Night Rider

Yes, rather, I disconnected the tie rod to be sure.

I used the one screw method, setting the idle by using the screw on the left throttle body (and backed off the right screw). After balancing I closed the right idle screw until it barely touched to eliminate slack if any. I can't see any drawbacks using this method. But even with both idle screws backed off, the idle is pretty high. Never thought about the injectors, I'll buy some fuel injector cleaner to add to my fuel and see if that helps. Never can hurt. You're very welcome That's how I finally managed to get everything tuned. I think my TPS at zero must be something like 250mV now, I nevered bothered checking it yet. The problem is that I can't get my RPM lower then 1200-1300rpm (on my tacho) without closing the bypass screws entirely and with the idle screws both backed off (as good as) all the way. So I set the TPS to 550mv for the higher idle (which is just an estimation, could be too low). That's how I did it, only I've openend the bypass screws only 1/4th of a turn to lower the RPMs as much as I can and set the TPS to 550mV to compensate for an idle RPM of 1300.

Hmm, not really fond of using propane but I thinking of buying some start pilot to spray on the throttle bodies to check for air leaks. My motorcycle has 40,000 KM at the moment. It had 13,000 Km when I bought it a few years ago but already had the clutch, front and rear axle bearings replaced as well as the rear monoshock. So I'm not sure if the 40,000 KM are correct.

I double checked everything when I set the TPS to 150mV, right idle screw was completely backed off as well the fast idle cam (and connection rod disconnected). I'm thinking either something inside is holding the throttle open or it's breathing air through an airleak (but vacuum balance is fine).

My engine has been running badly for quite some time now: stumbling and stalling at idle, misfiring through the airbox at steady RPMs, occasionally knocking when I twist the trottle. Only to get worse on hot days. Last year I've brought my bike to the dealer for a tune up, but that didn't really solve the stumbling at traffic lights and the coughing through the airbox. I've expected it was running too lean for a while. After reading all the TPS and throttle balance topics on this forum - and last week I had a few days off - I decided to try doing it myself with a little help from a friend. I first tried following a MG workshop manual, but it was so badly translated I ditched it quickly and switched to the forum method instead :-) First I've set the TPS to 150mV with the rod disconnected, idle screws and "choke" cam backed off. Then I adjusted the idle screws for a TPS reading of 520mV. What I discovered is that, even with the air bypass fully closed it was impossible the get an acceptible low idle: 2-3000 RPM when hot, if correctly set to 150mV. So i went for "Micha's method" instead and set the TPS from idle. I tried to get the idle as low as possible: 1300 RPM on the tacho, with bypass opened 1/4 of a turn and barely an offset from the bypass screws. Then I've adjusted the TPS to 550 mV (just a guess for that RPM, should be maybe set higher) and rebalanced the throttle bodies. However, the idle is a bit high, my motorbike is running a lot smoother now at slow speeds through traffic and mpg has gone way up. No sneezing at all. It does knock sometimes when I open up the throlle between 3-4000 RPM, so it isn't perfect but I managed to get it a lot better in tune then my dealer (well respected here) managed to get it. Still, there is the problem of the high idle, it's impossible to get it lower without closing the bypass screws entirely. I suspect two things: airleaks? or aren't the throttle valves fully closing anymore? I don't suspect the rubbers: they only seems superficial cracked and I've replaced them two years ago. And I measured the TPS and the voltage is increasing smoothly from 150mV to 4.85mV, so I think it's ok as well. But I did notice the springs underneath the throttle bodies are very dirty and seems to be dripping fuel a little bit on my garage floor. Do they breath air? (I've been reading the "Throttle Body Seal Replacement" topic with great interest.) I mananged to balance my throttle bodies very well, I don't expect to get the throttle bodies balanced with air leaks. What I do notice is that I had to twist the TPS a lot to get it to 150mV, could it be the throttle bodies aren't fully closing anymore after all? Or maybe I'm overlooking something? Does anyone know what the correct TPS reading should be around 1200-1300 RPM? A lot of questionmarks, I know :-) (I hope my English grammar is understandable, I'm not used writing this technical. ;-))

I got a bike with an external fuel pomp but another setup I haven't seen on any other V11. Not sure if it's factory default or the previous owner changed it that way. Basically the oil cooler is lowered to where normally the voltage regulator is placed on other bikes and the fuel pump is placed above the oil cooler with some heat shielding. The horns are also on top of the oil cooler and the voltage regulator is placed behind the oil cooler. Never had any vapor lock problems so far. Vapor lock, for certain. All the external fuel-pump models are susceptible to it. Symptomology is exactly as you described: nice, spirited ride on a warm day to get the motor hot, stop the bike for longer than a quick fuel stop & let the fuel lines get heat soaked, & the bike fails to start. Once everything cools off, it's back to normal, no signs of failure. Only thing that can be done is either: A] Swap the fuel tank & pump for the late model one (where the fuel pump is inside the tank to keep it cool & protected from the heat off the motor) - expen$ive! or B] try to insulate the fuel pump & attached lines as well as possible with appropriate materials (there's stuff out there in meat-space that you can use for this: check with homebuilt airplane supply catalogs like Aircraft Spruce or racing car parts places like Summit, JEGS, etc. for hi-temp insulation.) Best o' luck to you!

Yes, seems to me too. I'm not sure how the headlight and instrument panel is grounded to the frame, but I would look in that direction.

*Exactly* the same experience I had, temperamental generator light, fluctuating brightness at night (too high voltage), you named it :-) I think I ordered mine at Stein-Dinse, I shipment is free inside Germany if I'm not mistaken ;-)

Seems you have exactly the same problem I had. 17-18V at start and all charging gone after a while. In my case I had to replace the voltage regulator. Do you have an generator light on your dashboard? You can easily diagnose the regulator and make sure it's not a wiring problem. There's an L-shaped connector leading from your voltage regulator with two wires. The white one is for your regulator light on your dashboard, the black one is the reference voltage for your regulator. You can open up the connector a bit and measure the voltage between the black wire and your regulator ground. If you find your 14V there, then there's something wrong with your wiring or bad grounding etc... But if you have exactly the same readings as when measuring directly on your battery. In that case you know your wiring is correct and your regulator has gone bad. (as was in my case) I replaced mine with a Ducati Energia one which was a bit cheaper then a rebranded Moto Guzzi regulator (and exactly the same), cleaned up all contacts and removed the extra grounding wire from the voltage regulator and my bike has been running fine since. (Much of this info actually comes from Kiwi_Roy, so thank him instead)

Hi Tom, That 17-18V was that during the starting, or also after your starter motor stopped spinning?

Ok, an update. I have replaced my regulator and have been driving my bike for a few weeks and still am amazed where suddenly all that power and torque comes from. :-) Charging voltage is how it should be, no more burned light bulbs, the generator warning light now lights up consistently after I turn the ignition key etc... Thanks for all the input and thanks Roy for all the information I received, I think I now know everything about the chanrging system of the V11 ;-) Still, the bike likes to stall at traffic lights when hot and pops around 2750 RPM but not as profound as before. I was thinking about re-syncing the throttle bodies but before doing that I examined the rubbers around the throttle bodies. Some superficial cracks, nothing on the inside. Put everything back together, started the engine as a checkup and then I noticed a drip on the ground that looked like oil. Where did that came from? Well it seems the left throttle body is leaking underneath at the spring. I guess if it's leaking fuel after a short run it must also be sucking air into when running. I'm betting that's what causing the popping and stalling. If found this thread on the forum: http://www.v11lemans.com/forums/index.php?showtopic=13643&st=0 Has anyone tried rebuilding the throttle bodied and found good replacement o-rings?

They also have a different regulator In the past, the warning lights were always a big mystery for me. You would never know which would come on after turning the ignition switch. Could be both, none, or either one of them. I've had oil pressure switch replaced and that solved the mystery of that lamp. Now it's only the generator light left. But I guess that mystery will solve itself also when I got my electrical problems fully solved ;-)

Sorry if I didn't make myself clear. I've meant that the regulator keeps overcharging, no voltage change when the headlight is turned on or off. I've been studying the regulator schematics you've send me Roy, I think I finally fully understand how the regulator works. It may have been 20 years ago that I've had some basic electronics in school. ;-) Going to pull out the bullet connector of the reference wire a bit so I can measure between it and the regulator body. If I understand correctly: If the voltage is 14 the high output should be "normal" because the regulator thinks it's fine. If it's less, the high output is normal too and the regulator is putting out as much it can. However, if it's higher the regulator is faulty because it should have reduced the voltage to 14V. ;-) If the regulator turns out to be fine it must be something causing a voltage drop in the reference wire (or bad grounding). I still highly suspects the regulator, because I've ran another grounding wire, rebuild the relay sockets and cleaned all contact points. Also, when cold the bike is way overcharging and the generator light never lights up. When it's hot there is not charging on the battery anymore (just checked it). But the generator light up when you turn of the engine or at idle (which is normal I assume at that 800 RPM). Yes, it seems like there is no grounding at all, but I've run another grounding wire and there was already a wire running from the regulator to the battery negative. (But I will do voltage regulator on the reference wire to be 100% sure ) I did found out that it's not the ECU shutting down that makes the bike act grumpy. Because it's only overcharging when cold, and then the bike runs fine. Later on it stops charging making the bike drain the battery. (Luckilly it was not the cheapest one). Like docc said: That's why it ran fine after I ran another ground wire: probably not because of the wire, but because the battery was fully charged again. I'm still puzzled why the voltage dropped to normal values then, and not anymore.

Hehe, I wonder how you came to that idea. You probably re-soldered a broken connection that way I guess. By the way, I tried switching the headlight off and on, like Vuzzi did, but that didn't changed a thing. (It shouldn't according to my wiring diagram.)