Manky's XS650 Yamaha

[Clive]

Thanks for your time Clive

You're more than welcome Andy, always nice to catch up!

[morrag]

Andy, I trust you had on board a charged battery, as your alternator is of the type that requires external excitation via the battery/brush-gear/slip rings, to its field coil, for an output to be achieved from the alternator stator. So, charged battery, clean slip rings, and properly bedded brushes. If all this is as it should be, you, or who ever is wielding the DVM, should see 14.2v dc across the battery at all rpm above tick-over. Unlike a PMA, which does not require separate excitation, yours is a Field control system, which will work very efficiently, if all these conditions are met, ok, Morrag

[Clive]

Battery was charged before we started, but once running at above tickover, no increase in volts were seen, in fact it was running on battery power only, with no more than 10v seen when it was running.
No output from the alternator was observed either at any rev range.

When we finished the battery was down at 6.5v but recovering nicely.

[stinkey]

Andy, I trust you had on board a charged battery, as your alternator is of the type that requires external excitation via the battery/brush-gear/slip rings, to its field coil, for an output to be achieved from the alternator stator. So, charged battery, clean slip rings, and properly bedded brushes. If all this is as it should be, you, or who ever is wielding the DVM, should see 14.2v dc across the battery at all rpm above tick-over. Unlike a PMA, which does not require separate excitation, yours is a Field control system, which will work very efficiently, if all these conditions are met, ok, Morrag

Didn't understand any of that ?

[Tony oily bike]

Aluminium bodied indicators. 10 quid a pair. I'll get them powder-coated black. I know some don't think chops should have flashers, but this'll be my every-day bike & I'd like some small chance of surviving in modern traffic. How many drivers now would spot, or understand, hand signals?

Key words there my friend, its your bike, and you build it the way you want, the fact that fellow Monkeys really like it is a bonus!  

Hand signals - I'm lucky enough to get the chance to ride a couple of old bikes every now and then that were made yonks before indicators, so hand signals are the only option!

Nice work from Clive, wise words from Morrag.  


These fibreglass pencils can be useful for cleaning
http://www.ebay.co.uk/itm/Fibre-Pen-Pencil-Abrasive-Cleaning-3-x-Fibreglass-Refills-Electronics-PCB-Etc-/122200385603?hash=item1c73b5e843:g:CMgAAOSwA3dYEjKP

http://www.maplin.co.uk/p/abrasive-fibreglass-pencil-kr61r

[BikerGran]

Field control system, which will work very efficiently

Ah, there's the problem - Mr Field's control system isn't working!

 

[Manky Monkey]

I lost control long ago Bobbi. 

[morrag]

A very rough check on field coil operation Andy, is to loosely "dangle" a thin feeler gauge adjacent to the alternator aluminium engine cover, and close to it. If the field coil is energising you will see a magnetic "pull" on the dangling feeler. Rough and ready but a reasonable indicator. Assuming that's ok, check between each pair of outgoing leads from your stator, that's the 3 yellow, or 3 white leads, and usually, & for most alternators of your type, it should give you a reading of around 1/2 ohm between each pair, & although I haven't got a specific set of resistance readings for your bike, that should be near enough! ok... Morrag. ps, if all else fails, post it down to me in a large Jiffy bag & I will sort it, ok

[Manky Monkey]

  I'll try the dangly thing next time it's running -I guess a small weight, like a couple of washers, on a string would do the same?
Just bought a new set of brushes.

[stinkey]

Shall I post my chop and trike too ?

[morrag]

Something like a 6" steel rule on a piece of string, 1/4" away from the case at around the "1/4 to..." position should be a good indicator, well that's what I use.....( no not brass, or titanium, or.... )

[morrag]

What's your elec. prob then Stink...?

[stinkey]

I don't do electrics ? I'm building my brothers chop (1976 z900 ) on and off for many years..using some of the original loom..I had a guy do the loom for me several years back..but changed the frame since..it seems to be a simple problem ( live wire touching ?) keeps blowing a fuse..
And similar thing on my trike ? Hopefully one of our fellow monkeys is coming to my rescue?

[Manky Monkey]

Electrics mean absolutely nothing to me, but there are several clever Monkeys here that somehow understand them.

[morrag]

Well, if you are blowing the same fuse each time, then you have to test the wiring/components within that circuit. For example, you might have 4 or 5 fuses in total, depending on the machine, one, usually 20A will cover the charging circuit, the others, fused at around 10A maybe, will cover front and rear lighting, another aux. such as the horn and indicators, etc. so once the particular circuit that the fuse is blowing on is identified, then start isolating a component at a time, logically, and with perseverance, all will be revealed , well, lets say usually........................ the fuse ratings and number off fuses I have selected randomly so your own wiring diag. for your particular model will have to be consulted, of course,.Morrag