Battery not charging!!! GRRRR

[clb]

ok just put an L5 engine into my L3 bike. Got it all running sweet, valve clearances done (whilst the engine was out), cam chain inspected (new tensioner put in), new exhaust gaskets, and K&N oil filter.

Brumbrum, come home after a 3 mile test ride, turn it off..... try to start it again, and the battery's dead. Figured out the charging system is not working. Did the rectifier test (with 3 batteries + bulb) all fine on that test, did the regulator test (ohms/resistance) didnt like that at all, that didnt read squat on all but 1 pin. I can run the bike for about 5 minutes before a charged battery dies, how do i test the AC voltage of the alternator??? Where do i put the two probes, and what setting should i turn my multimeter to??

ps, new rectifier/regulator on way, just really want to test the alternator, voltage across battery when off: 12v, charging voltage across battery: 12v LOL ohhhhh!!!

[cargo]

Not certain I can help with the charging issues if thats what you've got...............

However seems to me to be a bit daft to replace the cam chain tensioner unless it was faulty ? And a new cam chain tensioner without a new chain as well also seems to me a bit pointless.

Also a healthy and fully charged battery will last 150 miles plus in daylight......................certainly my race bikes will do 150 miles + on a full charge

[clb]

yeah, stole the new tensioner outa my old engine.

hmmmm, well its defo not charging it itself the voltge is only 12v when running

[cargo]

Sounds like a ret/reg issue common enough problem

I assume you looked into your "new" engine to make sure the generator rotor and coil is actually there ?...................and plugged in ?

[clb]

yeh yeh its all in there swapped them about and now have about 50v ac at ~4000rpm+ .AND continuty through all 3 yellow wires up to the rect(regulater woohoo. If its not the regulator anything else to look out for?

[parby81]

yellow wires from genny go into reg rectifier. if they are the correct voltage (which i believe is about the 50v ac at 4000revs you mention) then test the brown and white wire coming out of the reg/rec on a a dc setting. What are these values? If the Reg/rec is working they should be around the 14v mark at about 4000revs. If its near the 12v that you are getting across the battery then the reg/rec needs replacing. If it is at 14v then you have a big drain on the system elsewhere. Did you swap over the loom including fusebox from the L5 as well?

[clb]

the battery now seems to be at 14-15volts when revved up to 4000rpm , the cause of it not charging that the white wire was corroded and had broken way down inside the actual loom (from me yanking around moving it to pop the engine in).

Surely if all the electronics are L3, there is no need to upgrade them all to L5? (even the alternator coils are L3 now )

Thanks guys

Colin

[parby81]

No, it was more if you had tried to use an l3 loom with the l5 fusebox or vice versa as the fuse box and some wiring was changed about around l5 from a four fuse box to a seven fuse one. If you've stuck with the same fusebox to loom then you'll be fine mate.

[jayboy]

ive got the exact same problem on mine. battery keeps getting drained. replaced reg/rec, must just be a toad wire somewere

[parby81]

check the wires from the genny to the reg/rect to the battery. At the end of the day they are always carrying current and with our lovely british weather end up corroding. Get the soldering iron out

[jayboy]

all done. chraging now. the block conneted was nailed. wired them all up individualy. just got 2 sort the miss fire out now :smt013