New batteries

[vifferman]

What he was thinking of, is that the battery has to have enough power to excite the coils in the alternator. The old Lucas alternators used permanent magnets in the rotor. So once the engine was turning you always got power generated. But a lot of later alternators use coil rotor magnets. So there is no magnetism in the rotor until those coils are energised. Not enough current in the battery to energise the rotor coils = no current generated. So push starting on a TOTALLY flat battery may not work. But it has to be TOTALLY flat for that to apply.

Aah.
True, dat.
When I went to test ride my VF500 before buying it, the salesdude jumpstarted it off another bike. However, the battery was so knackered that every time he went to disconnect the leads, the motor would conk out.
Same thing happened on my VFR750 when the R/R was toast. The battery was fine, but flat, and there were insufficient ergs to get anything to work. So, I charged it up, and that was just enough to run the bike as a total-loss electrical system as far as the dealer's about 3 km away, then it died.

[nudemetalz]

Well, the VT came back....
the mechanic multimetered and tested the charging system and got a reading of 18 volts !!!!!!!!! Basically cooking my new battery. That's why I couldn't figure out that it had little acid in it after less than 2 weeks.

So the R/R is knackered.
Malcolm of Econohonda has kindely got one on the courier to me.

BTW : If you need any Honda parts, he is the man !!!


Cheers
Chris

[Motu]

What he was thinking of, is that the battery has to have enough power to excite the coils in the alternator. The old Lucas alternators used permanent magnets in the rotor. So once the engine was turning you always got power generated. But a lot of later alternators use coil rotor magnets. So there is no magnetism in the rotor until those coils are energised. Not enough current in the battery to energise the rotor coils = no current generated. So push starting on a TOTALLY flat battery may not work. But it has to be TOTALLY flat for that to apply.

Like XS650s,with a flat battery you can push it down the biggest hill all the way to the bottom and it won't start.Took me awhile to cotton on when my XS1 had it's first flat battery - it just seems so wrong to hook up jumper leads to a kick start bike...

[Flyingpony]

That might explain why my old Suzuki always started even without a battery but the old Honda required a battery, probably with a charge too. The Honda was always a real bugger to get started.