Modern Vespa

Greetings everyone,

I have this mystical electric start problem, 2007 gts250ie, very frustrated after going through a series of maintenance, smooth running but short lived, hope to find guidance here to enlighten me. Thank you all in advance.

Recent replacements last 90 days
Voltage regulator
Battery
All fluids

Runs perfectly thereafter, parked & hookup battery tender for 2-weeks. Today while attempting to start, the dash shown initial cycle check battery only has 2-bars, cranks weak naturally will not turnover. Multimeter test battery at 13 volts, resistance in battery cables at 1.8 volts, attached photo for correction.

The second attempt is completely no power, no dash display, nothing requires power works. I am completely lost and have no directions as to how to further diagnose this problem, please help.

Lastly, I have to confess the scooter was knocked over when parked , nothing broke but minor scratches. Started up normally on the ride home and have not ridden since.

The 1.868v reading on the meter’s diode test range is pretty meaningless. What do you see with the battery connected, the meter set on the DC voltage range, the meter leads on the + and - terminals of the battery, and
1) the battery at rest — not trying to start the scooter
2) what does the battery voltage drop to when you try to start the scooter.

I think you have a weak or dead battery.

Thank you for the prompt response.

Battery is new = 13 volts at rest whether it’s connected or disconnect
Started every time since replacement last month.
Parked 2-weeks with battery tender, today the test showed 13 volts as well.
First attempt, The engine cranks weak, won’t turn over, no start.
Second attempt, no power whatsoever so can’t be tested hence the question of problem.
(double checked all connections, brake lever, kill switch & gas etc…)
Could this be the safety/security issue when the scooter was knocked over before?
Please note that I was able to start & rode home that same day.

Your continued suggestions & comments are gratefully accepted and appreciated.

The battery may look good, measuring 13v now, but what does it read when it’s trying to crank the engine?
It may have been damaged when the scooter tipped over.

Have you tested your fuses to ensure none of them are burned out?

Is this battery hold down strap just removed for the photo, or is it missing? I'm wondering if the positive terminal could have contacted the frame and burned something out.

If you have a car battery and jump cables handy, I'd be trying those and seeing if the bike turns over easily with a known good battery supply. Batteries can develop bad internal resistance so while they show 13 or more volts with no load, they can't deliver any decent current to start a motor. Battery faults happen much more often when they battery is warm/hot.

Updates and thank all chimed in enthusiasts.

After I disconnect & reconnect both +/- terminals, the dash is revived, but still can’t crank, turn over and start (see photo-1). Repeated disconnect/connect a few times, found a sweet spot with luck, the engine finally can barely start, continue idle a few more minutes (see photo-2), can start at will now.

Based on this exercise, please feel free to comment and correct my findings. Thanks.

“Deltran Battery Tender Jr” failed to perform, battery drained beyond voltage required to start despite the 13 volts false reading.
Bad battery or battery tender? Definitely don’t want to jump start after a week of storage.
Your thoughts please and thank you very much.

Strange If it's a dead battery problem, "jiggling" the wiring harness shouldn't suddenly get it to start... is it possible there's a bad connection inside that red wire splice? Can you test continuity from the battery to other end of wire and see if anything changes when "jiggling"?

What's the battery voltage when it's cranking? Running?

Is there a battery shop locally? If you bring in a battery, they will often load test it as a courtesy service.

What does your voltage drop to when you attempt to start?

For goodness sake, unwrap the abortion of a join in both the + and - wires, and re-make the extensions properly (crimp butt connectors, solder and heatshrink). Personally I'd also make the wires the right length so that the battery can be turned round to match all other GTSs with the terminals on the RH side. This might eliminate the extra length on the +ve wire.

A previous owner or incompetent shop made a complete bodge of that.

Thank you for the positive and encouraging support comments.

Honestly, I have never had a pleasant riding day (one problem after another) since the acquisition of this scooter despite the low mileage & good conditions and it does appear to be the fault of the design build.

Considering I only have a background of Auto-101 in high school decades ago, this has been a challenge of a steep learning curve in maintenance & repair but that’s not terrible thanks to your support.

Recapture replacements & intermittent start problem.
Replaced Voltage regulator, battery, all fluids & other minor parts.
Battery tender connected when parked.

Normal behavior when ridden daily
Battery at rest = 13 volts
Cranking = 11 volts
Started = 13 volts

Abnormal behavior when ridden weekly
Battery at rest = 13 volts
Cranking = engine primes, cranks but won’t start, power shutdown completely on 2nd attempt
It appears to be the battery is drained but measures 13 volts as it should.
It's difficult to jump start since the jumper cable alligator clamps are bigger and does not fit well in battery compartment and only works randomly.

Questions
Problem associated with battery, wiring or relay?
(local auto parts stores do not offer load tests on motorcycle batteries, “Batteries Plus” might?
How to continuity tests on battery cables when they are wrapped among others & redistributed to different areas not color coded?
I will tidy up on the extended connections on both battery cables as suggested.
Please advise and thanks.

Wiring problem for sure. That includes anything in the way - and I'd suspect the starter relay first off. I've had to replace one in six of the nine Piaggio scooters I've owned.

Dirty contacts inside due to poor voltage at some point.