Modern Vespa

Hi All,

After 5 years my original battery (Yuasa YXT12-bs) finally gave up the ghost. Given that there are only a few weeks or days of riding left here in the great white north, I raced out to get a new battery and install it immediately to get the last few rides in. After charging it up i installed it and rode to work (20 minute commute). It started right up after work but after arriving home and letting it sit for 10 minutes I went to start and it was dead. So on the charger again. Same thing the next day. I don't have a voltmeter yet so haven't been able check the voltage when at idle or higher revs. But I am wondering if the battery might not be charging due to:1) the relatively short commute; 2) the fact that it has been so cold of late that I am running the heated grips constantly and;3) construction has slowed traffic to the point that for at least half the commute home I am sitting still in traffic. Normally I've been able to turn the heated grips off for the afternoon ride home but temps have been hovering around zero (32F) most days and mornings are -4--8 (~18-27 F) so they stay on. Anyway I am hoping to ride until there is ice but can't say I am confident that I am not discharging the battery on the commute..... i guess that it will recharge some at work and likely crank over for the return trip. So to my question after the rather long intro..Is it likely that the heated grips are drawing enough to prevent the battery from charging?

1,2 and 3 will definitely prevent your battery from charging. I don't know how much current your heated grips are drawing but I suspect that they also hinder your battery from charging fully. Invest in an inexpensive multimeter to check current with and without the heated grips turned on. I hope you get it figured out.

Thanks Hachi, that's my plan, just waiting for the voltmeter to go an sale at the local Canadian Tire. The grips are rated at 30 watts on low and 45 watts on high which, I think converts to about 3.8 and 2.5 amp draw respectively.

Cheers
Mike

The Leader engine can only supply about 4A extra while running the engine, and if it's cold the battery charging will need some of that.

That said, I have got heated grips fitted to my GT200, but if I've used them I'll put the bike on the battery tender immediatelyy afterwards.

It is worth checking your charging system - make sure the regulator is indeed charging the battery properly. If it isn't you make have a 'weak stator' - which usually means weak magnets on the flywheel, so actually the rotor part. I've heard tell of them being re-magnetised. It could also be one winding of the stator is open circuit.

Thanks Jim, I am really grateful for all of your advice on this forum. I am entirely at fault here as I've gotten pretty lazy with the battery tender and given I have an un switched powerlet outlet in the knee pad is pretty much inexcusable. In any event it looks like winter is arriving with a vengeance this weekend (-20 and up to 20 cm of snow) and the riding season is likely over, so I will have plenty of time to suss out the problem for next season. Will repost when it's figured out.
Cheers
Mike

Okay, so I bought the multimeter and checked the battery immediately after charging and it was at 14.3 v, started it up and let it run for a bit, dropped to 12. 4, turned on the grips (high) for about ten minutes and n
Meter still read 12.4, same on low ..?? Not sure what this means, I had expected it the voltage would drop when the grips were on.
Mike

If it's not going above about 13.5V when the engine is running (but grips off) then your battery isn't being charged properly.

I had a recent issue with my battery. It would start up, I'd ride it, park it, try to start it.... Nothing. When I took it in, the newer battery was damaged. It turned out to be corroded where the wires none tend to the battery. It shorted it out. Those were all cleaned up, new battery installed, no more problems.

I've very recently started using a battery tender in the winter when I run the heated grips. The GT200 charging system doesn't seem to be able to handle running the grips and charging the battery, even though 'on paper' it should be able to.