new battery or something more serious

So it is slightly high as Yamaha specs it at 14.5V +/- .3V. Anything that will cause a voltage loss in the Brown wire that goes from the output of the ignition switch back to the Regulator assembly can cause this. The most likely is the ignition switch itself, but would also include the connectors for the ignition switch, the regulator assembly and associated wiring.

Since you seem to be still having some DMM irregularities I would suggest confirming the voltage with another meter.

 

reading should not go above 14.8 volts at 4000 rpm 15.1 not too bad keep an eye on it . this is indicative of a failing Voltage regulator

 

Thanks both.

It's interesting you mention the ignition switch/wiring, because last week when starting, the engine started, and the starter motor stuck 'on' whilst the motor was running so I turned off and restarted.
Also, historically (last time a few months ago), when I turned 'off', on the toggle switch on the right-hand assembly switch, (and/or the main switch key) it blew the ignition fuse, and it would not start until I replaced this.
Spraying electrical cleaner into the main switch key-holder, and the right-hand on/off switch toggle and push-start button switches seemed to rectify this issue, but from what you now inform could identify a connection issue, rather than a small amount of crud or damp affecting the system(?)
I'll start with the switch, and check all the connections (and blocks) involving the brown wiring between the switch and the rectifier itself, and report back any findings, with results. (it could be something quite simple, like a worn cut-off switch connector, or push-button worn? They have both had potentially 38-40 years of daily use)
I'll also try and source an alternative meter for my readings.

Later, and Thanks again!

Kind regards.

 

those grooves in the brushes shouldn't be there, can you find what made them? if they were flat the charging system would work better

 

I'll have a look at them again Polock.
And if they need to be flat, what is the best procedure to follow - nail file, for instance?
Regards

 

if the charging system works now, don't mess with them. now that you cleaned the rotor maybe check the brushes in a few hundred Km.
if you file them, they might be worse. normally they should be flat

 

Identified the very small oil leak as coming from the nozzle o-ring at 7 o'clock below the left hand crank shaft oil seal and housing.
Will replace both, when I can get the actual housing off?
Got the three retaining screws out with impact driver, but the actual whole housing won't budge.
How do I get this off please? (pics supplied)

Kind regards.

 

Replacing Alternator Seals in XJ700N with Pictures (applies to all XJ models)

The bearing may be a tight fit to the shaft. Use a bearing puller, but don't put too much pressure on the housing or it can crack.

 

Thanks k-moe
Just got to figure out what size puller is required (jaw width?). Is it at least 85mm, which is the distance across the diameter of two of the three flanges?
Regards.

 

My three-jaw puller is adjustable for width.

Looks like this:

 

Yeah. Thanks k-moe
Got set of 3 coming Mon/Tuesday
Regards.

 

Just had a look at the brush ends, Polock. I hadn't looked at them for about a fortnight since the bike has been off the road whilst waiting to be shipped to fabricators for new stainless exhaust system.
Before I took the bike off the road (removed the old exhaust system, with a 2" square hole in the top of the collector box!), I had done a 28 mile run to my sisters and back. (and it sounded like a Sherman tank on the way back - lol!) I had just cleaned all the rotor and stator etc.
The brush ends are now FLAT again, and not CONCAVE, as they were before I did the cleaning!
Just an observation I thought you might want to be aware of?
Could it be that a smear of oil, at the point where the brush ends engage with the rotor face had something to do with it? There was a tiny 'blob' of oil on the face of the rotor, and I recognised the leak as coming from the oil nozzle small 'o' ring top area.
Anyway, I also noticed that I had set out with a 12.4v reading across the battery (with the light ON), and when I returned the reading had risen to 12.8v (after about 24 miles' run)
Should get the removal tool for the alternator shaft housing, and the two (one big, and one small) 'o' rings arrive on Tuesday. Already got the oil shaft seal.
Also set up some leads, so I can do the 'current test', on the stator end connectors shown in thread earlier in pics. ( I can't do that though, until I have the bike back with new exhausts on July 3/4)

Regards.

 

never a bad idea to give that rotor a wipe off with brake cleaner before you close it up. just to get your grubby little finger prints off
don't get in on the stator

 

What's brake cleaner's equivalent in UK please?
Is it brake fluid?
Regards

 

here it is on Amazon UK https://www.amazon.co.uk/STP-GST72500ENP-Brake-Parts-Cleaner/dp/B009GKI88G

any automotive parts store should have it

 

Electric motor cleaner is a better choice. It won't damage the laquer on the alternator windings if you happen to mess up. It does cost more though.

 

Thanks both for options
I've got electrical cleaner which I've already used, so I'll go down that route
Regards

 

Just arrived.
'o' rings not til Mon/Tues though.
Shall proceed to removing shaft housing, in preparation. (and I shall be careful!)
Regards.

 

Is is the case that, you are only able to get two 'grabbers' on two of the lugs on the front of the housing?
The lug in front of the oil nozzle oil ring is very difficult to get an arm behind(?)

 

Rapidly losing patience with this.
Got the housing off ok, and the oil nozzle.
Then removed the old oil seal, opened the replacement one, only to find that I had been sent one that is too big.
To top it all I damaged the old one trying to remove it!
I cannot find the oil seal listed on the RJ Seca parts fiche, the two 'o' rings and the housing are listed but can't see the oil seal listed and numbered.
The one I was sent is listed as HL - 574567 (manufactured by Sifam, and also has 'SF44-B6 SEAL 26 on the label) and is in pic supplied, with old, damaged (so now useless) original next to it.
Please, does anyone know the actual OEM number for this rotor housing seal, and/or it's afterpart number?
Fed up of wasting money on parts that I cannot return once they've been opened?

Await your responses.
Regards.