B11 START ISSUE

[Emanuel]

Starting issue on my 06 Breva 1100.
The bike was put in the garage for two months, battery removed
(A couple of days before I got some rain)
Two months later pushed the start button: "clanck" but no crank. Shit... I thought I wouldn't go through this again when installed an MPH-like cable kit two years ago...

I spent a whole day together with a friend, an automotive electrician, trying to figure out...
- battery used is brand new and poles are clean
- earth point over the start motor cleaned
- ecu sockets cleaned
- fuses are fine
- engine off, I get 12,8V on battery poles, on dashboard 11,8V.
- engine on, 13,8V on poles, never got more than 13,6V on dashboard

We found out is that connecting the start button to the start relay, thus bypassing the ECU, the engine starts perfectly.
Seems like the ECU sees something it doesn't like...
Any clues of what can be the cause?
How indicative is the dashboard reading?

And last, what will happen if I just leave it like that (ecu bypass)?

 

[john zibell]

ECU is sensitive to battery voltage when starting. The battery voltage should be a bit higher at the battery, however the lower reading at the dash is normal due to resistance in harness wiring. Even though the battery is new, it seems low. Should be a bit over 13 at rest, and about 14 volts with the engine running. If you leave the ECU bypassed, the computer controlled starting will not function (release button and engine continues to turn over). If possible, try jumping the bike with a car battery under ECU control and that will tell you if it is a battery issue or not.

 

[guzzijimbo]

I think there is a safety circuit built into the ecu, I've had the same problem, try this, put a test light onto the spade terminal on your solenoid and press the start button, you will get your "clunk" and the light will light up for a millisecond, take the wire off the solenoid and with the test light on the wire press the start button again, you may find that the light will stay on for about 2 seconds.

Moto Guzzi's inadequate wiring (under size) and a bit of ageing will cause a hell of a draw, it should draw about 5 or 6 amps, as I understand it. When I tested mine the amp meter went off the dial about 25 amps, the ECU is monitoring the battery etc. and I suspect, reading this as a major short circuit and cancelling the order to start.

If you put another battery in parallel with yours or hook up a battery with greater crank ability it should start right up.

The battery I had in my bike was an SSB brand with 330 cca and a bit of age on it, I had been using an alternative start button that I had installed, running straight from the battery through the alternative button and on to the solenoid, this always spun the bike up very well, this battery is now doing a splendid job in another 1 liter bike. I replaced the battery with another, same brand same strength and haven't had a problem since, the message is that battery quality and cca is critical in the extreme.

This is all rather reminiscent of Auto immune disease in Humans.

 

[Sport1200]

These bikes need a starter mod done to the wiring- wires are insufficient. Run a heavy wire via a fuse from the battery positive to the wire that supplies the starter relay. (Cut wire first from harness- yellow IIRC) Did it to mine. Crap design.

 

[john zibell]

These bikes need a starter mod done to the wiring- wires are insufficient. Run a heavy wire via a fuse from the battery positive to the wire that supplies the starter relay. (Cut wire first from harness- yellow IIRC) Did it to mine. Crap design.

Documented here. https://www.guzzitech.com/forums/threads/modern-no-start-issue-solution.4908/

 

[2Laner]

Just back from a overnight camping trip. My 08 Sport failed to start at a gas stop. All too random occurrence! It finally did after numerous attempts and about 15 seconds depressing start button. I was afraid to turn it off or do more riding. New battery this year, had just cleaned ground connection on motor and battery terminals recently, starter mod done long time ago. Starter relay has been replaced. I have cleaned and applied dielectric grease to all electrical connectors recently except the ECU. My question, how to remove connectors from ECU? I did it once when I sent in ECU to Todd for re-flash but that was a long time ago. Is it necessary to remove tank? Where are tabs to release ECU connectors? If cleaning these connectors up doesn't fix this annoyance, I may be getting something else! I love this bike though, 56,000 miles so far.

 

[Wisconsin v7 Racer]

Just because the battery is new does not mean it can't fail. Easy to check that first to rule that out.

 

[Earl Bowman]

I'm having the same starting issue with my Breva. I installed the MPH wiring kit about 3-4 months ago, never had a starting issue it just seemed like cheap insurance. Everything was fine for a couple months. I've been really busy and haven't ridden in about 2 months, but the bike is hooked up to my battery tender and usually fires right up. Today I go out, switch on the key, the dash lights and cycles, fuel pump purrs, I hit the button and get a big "Thunk" from the solenoid engaging and then nothing. OK, dash board says 13.4V but I know that's not all getting to the starter so I hook up my battery charger set to 10Amps and get 15.4V on the dash. Hit the button, "Thunk" and nothing! I tried several combinations of charger, no charger, tender, no tender, prayer, nothing worked. UNTIL, while standing there contemplating if electrons really do flow, I look down and notice 14.3V while hooked up to just the tender, hit the button, BINGO, she starts and roars to life! Good fast idle, voltage comes up and stays around 14.2, all seems good, so after about 2 minutes I shut her off and immediately try to restart...THUNK and NOTHING! I've checked and rechecked fuses, cleaned battery terminals, I pulled the starter and it is free, cleaned starter cable connections and ground cable connections which had been previously moved between the ground lug and engine case for more surface area contact. I'm 2 1/2 hours into this and I'm stumped!

 

[Emanuel]

Voltage only tells half truth. You may see good voltage but the battery doesn't actually have the strength (Amperes).
How old is your battery? Perhaps is time to replace it.

 

[Earl Bowman]

Voltage only tells half truth. You may see good voltage but the battery doesn't actually have the strength (Amperes).
How old is your battery? Perhaps is time to replace it.

Yes, It's probably time. It's over two years old. I have a new one on order.

 

[Brian UK]

The only voltage which counts is what the battery drops to when you hear that clunk.

It does sound as if your battery is past its best.

The only other problem I have had is the solenoid. The brass covered plunger was covered in sticky grease (from manufacture). I cleaned tis off, put a drop of oil on the solenoid pivot, reassembled and all was good.

It doesn't seem to take much to stop this system working.

If you can get at it, it's worth trying to put a link from the top big terminal on the end of the solenoid and the spade and see if that starts the engine, assuming ignition is on.
If it does, then the volts via the start relay are low.

 

[Earl Bowman]

Thanks, Brian. As I said I've done the MPH starter relay wire around but I guess if battery amperage is low it wouldn't necessarily help! I will pull the starter again and have a peek at the brass plunger contact on the solenoid. I considered taking a look when I originally had the starter out, but was in a foul mood and not really up for the task at the time. Thanks again.

 

[NPS]

I had my wiring loom out last year. I examined each connection and found a few connections that looked quite weathered/corroded Breva 11 2005). The bike had been on the same battery from 2006 to 2017. I did have periods of slow starting due to low charge as not been used for a month. At six weeks it would need a charge to start. But starting was not really a problem. During those years I did improve the earthing of the starter but not the relays. Still today Im on the original relay wiring and earthing apart from moving the engine earth to the bolt above the starter, on to the bell housing thanks to recommendations here. My take on this is that it may be down to the quality of the battery although voltage drop across the wiring I see but has not really affected me. My typical voltage at the dash is 12.6V.

 

[Earl Bowman]

Update to my starting issue: I purchased an Antigravity Lithium ion battery from Guzzitech, 480 cranking amps, and she fired right up, first time! Problem solved! Even better my old glass-mat battery weighed 13 lbs, the new Li-ion battery weighs 3.1! That's almost 10 lbs lighter! So the Guzzitech reverse-cone muffler and Y-pipe I added a few months back and now the new battery have allowed me to drop almost 20 lbs from my Breva. Now that's a diet I can enjoy!