Running badly; thoughts?

[delagem]

it LOOKS way advanced, but the timing plate looks a bit beat up

Ok, we can't have that! Timing plate repainted, with new gold leaf markings!

IMG_1111 by michael delage, on Flickr

Unfortunately, as you can see, after finding TDC using a dial indicator, I can't slide the timing plate far enough over to line up with that. So I painted a new mark next to better line up with the TDC line on the timing plate. What would cause this? Likely an aftermarket rotor? I can't imagine Yamaha letting parts like that thru quality control...

The pickup is not adjustable, at least as far as I can see? No oblong hole, and no hole to rotate the stator either:

IMG_1112 by michael delage, on Flickr

As a followup to that, I see this statement in the Service Manual that says "Ignition timing is not adjustable."

Screen Shot 2018-06-01 at 9.16.45 PM by michael delage, on Flickr

Gary, thank you so much for your help this far! Never would have gotten this far without you guys here. I'm just puzzled on how to proceed from this point.

any thoughts?

Michael

 

[gggGary]

The pick ups have two mounts they a have slots under the washers the top pick up mount is kind of hidden by the side cover.

If timing is wrong and you need to slot the pick up flanges do it. But first remove the stator and double check this.

 

[delagem]

Oh, jeez. The light bulb goes off. Some hack who's been working/wrecking on this previously, had the flywheel off, and "lost" the woodruff key. So he guessed on something close enough...

That's my latest guess. Anyone got a better idea before I have to pull the rotor?

 

[gggGary]

Looks like you have an 80 or 81 pick up they didn't slot the pick ups at first but realized that was mistake, 82-83 pick ups are slotted but easy peasy to slot the older ones. The rotor has a front and back but the relationship is not cast in stone, rewinds, and aftermarket rotors may have inaccurate TDC indications. that timing plate attached to the stator can also be moved a bit.

 

[gggGary]

You GOTTA use a XS650 specific rotor puller, or you will become your own PO LOL.
https://www.mikesxs.net/yamaha-xs650-puller-alternator-rotor.html

 

[gggGary]

Long as you're here and have the stator off; check the resistance between the rotor rings; 5.6 ohms is ideal, just over5 to 6 ohms is acceptable, hold your meter leads together, subtract any reading found from your rotor reading. Hold the leads on the rings for several seconds til the reading stabilizes.

 

[gggGary]

find the three wire pick up connector back near the frame down tube, open it and ohm the pick ups, both orange and gray to black should read 570 ohms +- 10% if they don't, pierce the wire insulation near the pick up coil and check again.

 

[delagem]

Long as you're here and have the stator off; check the resistance between the rotor rings; 5.6 ohms is ideal, just over5 to 6 ohms is acceptable

I love variable results. You may remember in the first post in this thread, I ohmed the rotor at 5.0 ohms. See the 3rd picture in post #1. Well, of course today it's 4.1 ohms. Sorry, no picture this time! I'm not convinced that's the issue, but it may be something to come back to.

I do have the flywheel puller you linked to, it's a common puller for Yamaha motors. Unfortunately, I need the internal thread version, which I don't have. I've ordered it:
https://www.mikesxs.net/yamaha-xs650-puller-alternator-rotor.html

Starting to run out of time. Traveling for work for a few days, starting Monday. To be continued in 1 week...

 

[gggGary]

My bad just grabbed xs650 puller didn't realize mikes had added a PMA puller, link changed to correct puller you found.

 

[5twins]

The pick-up mounts on my '83 are not slotted (but they will be, lol).

 

[5twins]

I've never seen a timing plate that needed to be moved fully to one side like that, and yours still don't match up to T.D.C. Might be time for a cam timing check, maybe the chain is off a tooth.

 

[gggGary]

I've never seen a timing plate that needed to be moved fully to one side like that, and yours still don't match up to T.D.C. Might be time for a cam timing check, maybe the chain is off a tooth.

That would only change valve timing?

 

[gggGary]

That looks like an aftermarket rotor.

This is how the timing mark looks on a factory rotor.

A recent thread talked about the mark being out of time and perhaps MOVING while installed on an aftermarket rotor.
Read this post....[URL="http://www.xs650.com/threads/10-cent-charging-diagnosis-please.51924/page-4#post-551323"]10 cent charging diagnosis please...[/URL]

 

[MacMcMacmac]

Isn't 2500rpm about the engine speed where the second ignition pickup takes over in at the fully advanced timing setting?

 

[gggGary]

IIRC the TCI has a map and chooses a gradually advancing spot between the two pickups till about 3K

 

[delagem]

That looks like an aftermarket rotor.

You're right, mine looks exactly like the one pictured on the mikesxs.net site:

Mikesxs.net rotor:

Shouldn't matter, right? Get the timing right, and all should be well?

The voltage is concerning, it should be charging better than 12.3v at idle. But with each test I did, I noticed the "at speed" charging was getting a bit better; last time I ran the bike at 2,400 rpm (best it would rev to), I saw 13.3v.

 

[Paul Sutton]

On the 81 Special the timing is supposed to increase in a linear manner from approximately 2000 rpm to full advance at 3200 rpm. I never observed this gradual change but instead saw a step change at approximately 2000 rpm to full advance. I suspected my TCI may have been faulty so installed the Boyer ignition and you can actually see the advance take place from idle to 3000 rpm. Also the TCI circuitry changed over those few years and some models may have had a better advance control than the 81.

 

[gggGary]

Charging break even is about 1200 RPM with everything in good nick and stock incandescent bulbs.

 

[delagem]

The more I look at these marks, the more I think the timing isn't off much at all:

Bike at idle:

IMG_1105 by michael delage, on Flickr


Repainted marks (the plate did need to be shifted about 1cm right, but that's still going to be inside the "acceptable range" indicated by the horseshoe on the timing plate:

IMG_1111 by michael delage, on Flickr


I'm still going to pull the rotor and check the woodruff key, once the puller arrives. But I bet there's going to be nothing wrong there.

What's the next idea once that's been eliminated? This second pickup that takes over somewhere around 2000-2500rpm seems likely, given that my problem occurs at about 2,400rpm. Does anyone know how to test that?

EDIT: Spec for the pickups, per the manual I have, is 560-840ohms (700 ohms +/- 20%). I had about 750 ohms on each. So those both check out good.

Screen Shot 2018-06-03 at 9.17.23 AM by michael delage, on Flickr

Michael

Edited to include proper manual spec and pic of the page from the manual.

 

[MacMcMacmac]

That's

You're right, mine looks exactly like the one pictured on the mikesxs.net site:

Mikesxs.net rotor:

it

Shouldn't matter, right? Get the timing right, and all should be well?

The voltage is concerning, it should be charging better than 12.3v at idle. But with each test I did, I noticed the "at speed" charging was getting a bit better; last time I ran the bike at 2,400 rpm (best it would rev to), I saw 13.3v.

That's the same rotor I bought last year and it had no timing marks on it.