Battery charger connection

[Wirelic]

Hi All,

I was reading in the service manual for K75/100 (Clymers, I think) that the battery should be removed from the bike before connecting a charger to it.  Wow!  This seems extremely inconvenient.  Does anyone know why?  How many disregard this direction and connect a charger while battery is in your bike?  Any bad experiences?
Thank you for your help. 

[The Mighty Gryphon]

First off, I charge my batteries in the bike.  I connect the trickle charger/maintainer to the accessory outlet above the coils.  I connect my big charger(if it's needed) directly to the positive terminal and any good ground point on the frame.

I can do this because my bikes have sealed, maintenance free AGM batteries where there is almost no danger of acid coming out of a vent like the old style lead acid batteries.  If I had one of those in my bike, I probably would remove it for charging to avoid the acid fumes and liquid venting onto the bike.

[Laitch]

To augment TMG's erudite post, here's the reason Clymer gives.

CAUTION
Always remove the battery from the bike’s frame before connecting the battery charger. Never recharge a battery in the bike’s frame; the corrosive mist that is emitted during the charging process will corrode all surrounding surfaces.

I'd remove it if it needed a slow recharge from being discharged but I haven't needed to do that in nine years of ownership. Another reason to remove it is if you only think you know what you're doing but don't really know, then attach the wrong type of charger at the wrong setting to the wrong type battery and it explodes. If it's out of the moto, the only damage will be to yourself, your garage or your house. The moto will likely be undamaged.   

The battery can remain in place during trickle charging but I don't do that either.   

[rbm]

Right Laitch.  And there is the danger of damaging sensitive electronics in the bike depending on the quality of the charger you're using.  Some low cost and poorly designed chargers either put put huge ripple on the line or the voltage is not accurately controlled.

I keep charger pigtails on my battery all the time but I also use a high quality smart charger.  It hasn't ever damaged a battery or an electronic item.

[The Mighty Gryphon]

Leaving the battery in satisfies two ways: laziness and a desire for cheap thrills living on the edge of disaster.

[Gio]

+1 on agreement for no need to remove ... I use a fused outlet wired directly to AGM battery for trickle charging - which also serves to power heated vest if needed.

[Wirelic]

Thank you all very much for your answers.  I really appreciate all of them.  I’ve been wrenching on bikes for over 50 years and can’t recall ever coming across a directive like that before.  My goodness, I’ve probably charged several dozen batteries while they were still on the motorcycles over that time span with never a hint of a problem.  I guess I’m either doing it right, have good charges or just dumb luck. 

But, I think I’ll adopt the method here discussed and eliminate any chance of a mishap.

[daveson]

If you mix up the battery pole connections, even briefly, you could cook the computers and other bits. Statistically, I'll guess that 999 people out of 1000 get away with it. Coincidentally I heard of another case of a cooked computer this way last week. It might be more often, a lot of people don't like talking about dumb stuff they've done, but I think it's good for a laugh sometimes.

Down this way, we can ride all year long, so I rarely use a charger, but for some unknown reason I prefer the lazy way.

By the way, never disconnect a jumper battery while the engine is running for the same reason, as one in a thousand have found out the hard way.

[Wirelic]

Good to know, thanks!