Hello - and to start with - a stator fault!!

[biaggi]

Hi there,

Wow I never thought I'd find so much info about this bike - it seems so rare!!

I have an XZ400 over here in England (identical apparantly except for the bore and a couple of minor details) which I brought for commuting to work on.

I recently had to replace the starter motor bushes (I did wonder where the oil came from until I found the Vision resource site)!!!

And now it seems my stator has gone. Using the Haynes manual (for the 550) I traced the fault back to the Stator. I pulled off the engine cover and to my horror I found all but two of the coils burnt to a crisp!!! Not only that but also a phillips screw (similar to the one that holds the stator on) was found loose inside. I've had a really good look round but cannot see where this screw may have come from. Anyone else heard of this? One clue maybe that the stator appears to have been replaced before (gasket sealant and mullered bolts gave it away) and I'm assuming the fool who did it left a bolt in there.

Anyway, would this bolt have caused the stator to burn out like this?

I'm going to replace it with one from Electrex and go through all my connectors as suggested elsewhere. Anything else I need to watch out for??

All the best :)

P.S. Sorry, what oil should I use? Standard or semi-synthetic?

[scootertramp]

you can pay MORE or you can pay less for oil. its all good. we had a discussion a while back. look for the thread on OIL. I came to realize as long as its good clean oil it don't matter. I use regular oil. I like castrol.  it's cheaper than synthetic but then again I am a cheapskate.
My stator is fried too.

[Walt_M.]

The 550s are rare, a 400 would be rare indeed! Do you have any specs, bore and stroke? Too bad about your stator but it can be fixed.

[sdinino]

For just a second, I misread what you wrote and thought you said there was a screwDRIVER loose in there!  :o

Double check the inside of the cover where the stator is mounted. The ignition pickups and the metal shields that keep the wires in place are held with philips screws too. In fact, I can't think of any other phillips screws in the left side of the engine except those inside the cover.

If you are fortunate and can get all those screws loosened without stripping the heads, replace them with bolts or hex-drive caps screws. They tend to get a little frozen in there, and you can't get enough torque on a phillips screw to extract it without stripping if that happens.

[Rick G]

All you need to get Japanese phillips head screws out is a Hammer impact, everyone who works on his own bike should own one . For you west coasters there available at Harbor Frieght  for 3.99  and they do mail order.

[Rick G]

We've have Visionaries  with 400 s report in from Russia , South Africa  and South America  . Your the first from GB.
I'm using  a synthic blend , But if your oil hasen't been redisigned by legislators as ours has   a good mineral oil will work OK, In the States  you need a motorcycle  or Racing oil  or some of the important additives  have been omitted. To repeat  DON'T  USE CAR OIL!

[biaggi]

Thanks for the advice guys.

I have an impact driver so will give that a go. Also have my Dremel if all else fails. I'll replace the bolts as suggested and apply thread lock.

There's not much difference in price between semi and mineral oil so I'll fill it with semi.

Details of a sort on the 400 can be found here:

http://home8.highway.ne.jp/crowsinn/garage/no10.htm

You can just about make out the basic specs. Mine does not have a fairing and is the same grey colour as in the picture. The paints not bad for 20+ years but the badges have faded and there are many dents and scratches. I'll get it re-sprayed at some point.

That mystery screw sure is a head scratcher. It's identical to the others in there but I've checked everywhere and just cannot find a home. I'll leave it for a few days - fresh eyes and all that and look again. I'm worried though having spent ??? on a new stator and having to make my own gasket etc I don't want anything to fail again causing more trouble and money!!!

As mentioned before is this the likely cause of the burn out or do I need to investigate elsewhere first?

All the best :)

[Lucky]

Download the "Fault finding chart" from Electrex & go thru test "C" to check the regulator/rectifier.  

Since the dammage is elecrtical in nature, as opposed to mechanical (burned not broken) then it's likely that this is a case of normal Vision stator burnout, and probably you'll need to replace the stator as well

A give away that it's "normal" gharging system failure is burned connectors on the R/R

the rotor is a big huge magnet and I don't remember if the screws are magnetic or not, but it sounds like it might be an extra that got left inside?  It's kind of an 'examine it & make a guess' call.

What you really should do is take care of the starter clutch bolts while you still have everything apart.  if they have a small peen mark on them then their still factory & should still be replaced.

one other thing to do while your in there is tighten up the balancer shaft Drive & Driven nuts.  these come loose and sound really bad as well (and are hard to diagnose)

keep writing & let us know how your doing, & ask lots of questions! :)

--Lucky

hmm... does the 400 have a balancer shaft?...

[Rick G]

I'll bet it does!  just with a differant balance factor.

[biaggi]

OK, will do. The chart does not seem to be working at the mo but will check again later.

The Haynes manual states an Ohmeter is needed to check the R/R - as only continuity needs to be checked, will a continuity meter do??? - forgive the ignorance, this is the first time I've ever had to deal with motorcycle electrics!!!

I've also checked the manual and looked for the balancer shaft drive & driven nuts but I'm not too sure what I'm looking for. Are these behind the shaft drive cover (on the left side)??

Sorry for all the questions but here's another one (last one for now - promise!) - what is the diameter of the 550 forks? I also need to replace the fork seals and want to know if the 550 ones fit.

Thanks :)

[Walt_M.]

My fork tubes are 34 mm. I just now looked at the Japanese spec page and it looks like the bore and stroke are 73X47.6 and it has about 45 hp.

[Rick G]

The forks are the same, you can get  a suitable seal, for less than the dealer wants, by going to an industrial  bearing supplier . Yamaha gets 38.00  for  apair ,here , and they are 4.40  apiece  at a bearing mart.