Distance the stator is offset from the crankcase?

[LioPrinceofCamarillo]

This is a bit of an odd question, but does anybody know the distance the stator is supposed to sit offset from the crankcase? I don't know if the crankcase on my bike has been modified at all, because when I bolt the stator flush to the crankcase, it looks like it sits half way out of the flywheel. I thought this couldn't be correct, so I've offset the stator about 3/8" with a couple of small washers on the backside of the stator so it's more enclosed by the magnet, taking care to not let it cause a short between the stator windings and the crankcase.

I need to know because I've been having a charging issue that I cannot solve. I've replaced the reg/rec with a brand new R6 spec model. In order to narrow down if the problem is within the loom, I've set it up so the loom is bypassed entirely, just separate wires running directly from the stator to the reg/rec, then directly through a main fuse to the battery.

After testing this setup, it still won't charge. The battery shows about 12.5v when revved above 3k. Putting the meter on the stator output connector, it's only showing around 1v AC on all three phases. The stator is a used, OEM unit I bought off eBay and I just got it rebuilt at Rick's Motorsport Electrics, so I'm reluctant to say the stator itself is bad. I have no other ideas for what could be causing the problem, other than by some strange reason the magnet in the flywheel has somehow gone bad, but I seriously doubt that it's the problem.

The bike is a stock, 1988 1WG 3EN1 model (imported) if it helps.

I'll upload some pictures once I pull the flywheel off again.
Thanks for the help!

[LioPrinceofCamarillo]

*Correction, there were only two 1/8" washers under each mounting bolt. So it's been offset more like 1/4" than 3/8", my apologies.

When looking at a mirror, this is how the stator sits inside the flywheel when offset with the washers. It looks like the back edge of the stator is about flush with where the magnet starts in the flywheel, as there is about an 1/8" of material before the magnet starts.


Does this look kosher?


Without the washers between the stator and the crankcase, the distance from the front of the stator at about the 12:30 position is about 1.68 inches to the case and about 1.02 inches from the back of the stator to the case. The three mounting bolts bottom out before they actually start to hold the stator on the case when I mount it without the washers behind it, hence the washers under the heads of the mounting bolts.


This is how the stator sits in the flywheel without the washers between in and the crankcase. I don't believe the windings are fully enclosed by the magnet, It looks like the back edge of the stator is about flush with the edge of the flywheel.

[reelrazor]

I don't think there's anything abnormal there, except your stator mounting screws are too long. Is that an aftermarket stator?

The magnetic fields from the flywheel magnets occupy space around the flywheel and will encompass the stator regardless of that offset

[LioPrinceofCamarillo]

The description on the eBay ad was that it was a used, oem stator for an American market FZR400, and it came with the same size bolts as those that were already on the bike. Looking up part numbers on the Yamaha website, all three years of American market 400's used the same 3BF model stator. My bike is is a 3EN1 model with the hoover pipes above the headlights, imported by the previous owner from South Africa.

I've since spaced the stator in by about another 3/8" so it is fully enclosed by the magnet, but it only increased the output to about 1.5 volts AC on each phase. I don't know if there could be a cross compatibility issue with the 3BF stator and the 3EN1 rotor, but theses are the last two components left in the charging system I can check. It has to be either one of those, or somehow a combo of both.

[Evilchicken0]

Like I said on 400greybike, buy one from a FZR600 3HE from a similar year 1988.

[reelrazor]

The description on the eBay ad was that it was a used, oem stator for an American market FZR400, and it came with the same size bolts as those that were already on the bike. Looking up part numbers on the Yamaha website, all three years of American market 400's used the same 3BF model stator. My bike is is a 3EN1 model with the hoover pipes above the headlights, imported by the previous owner from South Africa.

I've since spaced the stator in by about another 3/8" so it is fully enclosed by the magnet, but it only increased the output to about 1.5 volts AC on each phase. I don't know if there could be a cross compatibility issue with the 3BF stator and the 3EN1 rotor, but theses are the last two components left in the charging system I can check. It has to be either one of those, or somehow a combo of both.

1.5V AC? Yeah, something is up. Sure your meter is AC scale? Stators and rotors.......pretty simple devices and no real reason they WOULD BE different. The permanent magnets in the rotor okay? (basically-strong).

Biggest issues we see are pickup coil compatability, not so much delta wound stator coils.

[LioPrinceofCamarillo]

I tried with three different meters: a cheap $5 Centech meter, a bit bigger and fancier $50 Centech meter, and a Fluke meter, though the Fluke is meant for HVAC (can measure VDC and VAC, but it doesn't have any scaling setting, I assume it has some sort of autoscaling). All gave around the same result. I've been looking for a 600 stator, as Evilchicken0 advised, and it looks like the 600 stator mounts to the cover and the rotor is mounted facing the other direction to how it sits on my bike. But the SKU for a 600 stator on the Caltric website is the same as the SKU for a 400 stator. So I assume, at least in Caltric's eyes, the 400 and 600 stator are interchangeable even though they sit in different positions on the bike.

[Evilchicken0]

The stator in the cover is a later design - they used it for the Foxeye and ThunderCat.
You want the earlier FZR600 the 3HE get a secondhand one off ebay