Should the Regulator be too Hot to Touch?

[5twins]

..... which can be caused by a badly stretched cam chain. The chain stretches gradually over time, just like a drive chain. Your adjuster is spring-loaded and compensates plus you re-set it from time to time so you may not notice any wear by looking at the adjuster. It won't plainly show you excessive wear like looking at the chain adjusters on your rear wheel would.

47K is quite a lot for an original chain. I'm sure they could last that long or longer if properly maintained but there's the rub. You should check and adjust the chain if necessary about every 1000 miles. Most of these bikes never received service like that. Original chains are usually toast by about 20K.

Check your timing at full advance with the light. As I said, that's important, more important than where it falls at idle. I'm suggesting you open the gaps back up a little. They may be too small now. Just don't make them as big as you had them (.35mm) because then you can't get it to time right.

 

[freddy3]

sgallaty: That makes sense. How do I check/correct that (cam alignment)?

 

[freddy3]

5twins: It's raining now, so I may not be able to re-check the (full advance) timing for another day or two. But I'll do that and report back the results. Do you want me to re-check the timing with the current point gaps or should I reset them to .35mm?

Re the cam chain: Because it's easy to do, the cam chain's been checked, regularly, a few times/season ever since I've had the bike, which is why it may still be in good shape.

 

[sgallaty]

I'm not sure we're making it clear to one another on the cam chain.

Tension is only part of the consideration with the camchain, the other consideration is the overall length.

5twins said it but I was thinking it - I can't quite figure how the two cams would get out of sync, but I've seen it happen. For example, the PO might not have kept the chain tight enough, and in so doing it could have jumped a tooth etc.

We're just trying to exhaust possibilities here.

 

[5twins]

There's a locating pin for the ATU that fits into a hole in the cam. At TDC, that pin or pin hole should point straight up or down. Here's a link that explains it .....

http://www.650motorcycles.com/CamTiming2.html

You can recheck timing either way, with current points gaps or after. It's so easy to do with the timing light. Rev the bike to 3 or 3.5K and shine the light on the timing marks. You should be on the unmarked slash at the far left when fully advanced.

 

[freddy3]

Tension is only part of the consideration with the camchain, the other consideration is the overall length.
5twins said it but I was thinking it - I can't quite figure how the two cams would get out of sync, but I've seen it happen. For example, the PO might not have kept the chain tight enough, and in so doing it could have jumped a tooth etc.
We're just trying to exhaust possibilities here.

Sorry, what's the "PO"?
Of course, anything's possible at this point. But I think it's relevant that the bike's never been ridden hard and I've been pretty meticulous about keeping the chain tensioner adjusted (and it's never varied more than about ~2mm in the 36+ years I've had the bike!). So I'd be mightily surprised if the chain could've jumped a tooth on a sprocket or gear. But I could be wrong.

There's a locating pin for the ATU that fits into a hole in the cam. At TDC, that pin or pin hole should point straight up or down. Here's a link that explains it .....
http://www.650motorcycles.com/CamTiming2.html

Okay, based on that link, I see what you're talking about, but removing the advance unit is a bit beyond what I can check or fix. (I keep the bike in a small unit at a public storage and there's no room within the unit to work on the bike and they don't permit people to work on vehicles in the parking lot. So all of my measurements/adjustments have to be carried out somewhat surreptitiously, which limits how much disassembly/how far into the engine I can go.)
But, again, I'd be very surprised if that pin could've jumped out of position.

You can recheck timing either way, with current points gaps or after. It's so easy to do with the timing light. Rev the bike to 3 or 3.5K and shine the light on the timing marks. You should be on the unmarked slash at the far left when fully advanced.

Yes, the timing light makes it easy to set the timing, so I'll recheck it at 3~3.5k rpm as soon as I can get out to the bike (when it's dry).

 

[5twins]

The pin doesn't jump out of position but if the timing chain has jumped over a tooth on the sprocket or the chain is really stretched out, that pin will no longer point straight up or down at TDC.

Another possibility is that the pin has fallen out and the ATU has turned or shifted on the end of the cam. That will throw the timing off and can happen if the slotted ring that holds the ATU on comes loose.

 

[freddy3]

The pin doesn't jump out of position but if the timing chain has jumped over a tooth on the sprocket or the chain is really stretched out, that pin will no longer point straight up or down at TDC.
Another possibility is that the pin has fallen out and the ATU has turned or shifted on the end of the cam. That will throw the timing off and can happen if the slotted ring that holds the ATU on comes loose.

Should I be able to see if the pin is missing (or turned/shifted) on the end of the cam when I remove the advance cover?

Also, when I re-check the timing (at 3~3.5k rpm), if it's off, I presume I need to rotate the timing plate (again) to realign the rotor timing marks to fit within the "F" lines on the stator. Is that correct? And, then, I repeat for the other cylinder?

I apologize for all the stupid questions. It's just been some time since I've delved into all this stuff.

 

[sgallaty]

> Sorry, what's the "PO"?

Ah, my apologies. Your bike didn't come installed with one. They are a feature on most of the bikes we get used. It's a defect that causes all manner of damage, including missing parts and stripped fasteners.

 

[freddy3]

Ah, my apologies. Your bike didn't come installed with one.

No PO, but you might appreciate a couple of the items my bike did come with:

 

[freddy3]

I just re-gapped the points to spec (.35mm) and then used the timing light to set the timing. Unfortunately, that didn't work well at all. The bike runs, but no where near as smoothly as it did either when I set everything by-the-book or when I used the dwell meter and timing light.

So, since the dwell meter/timing light combination worked well and was alot easier than setting everything statically and my dwell meter only supports 6 & 8 cylinders, I ordered a new digital dwell meter that supports 2-cylinders. Hopefully, it should be here in about a week in which time I'll try again and report back my (hopefully perfect) final results.

 

[5twins]

You found a 2 cylinder dwell meter? Where? Got a link?

 

[5twins]

Something I just noticed in the earlier pic of your new advance unit - you have the notched retaining ring installed backwards. There's a raised lip around the I.D. of the ring and it should face out .....

Having the ring on backwards may have allowed it to loosen up, letting the locating pin fall out, and allowing the ATU to shift position on the shaft. I would remove the ATU and check that it's still located in the proper spot. You can't tell by just removing the chrome cover, the ATU has to come off.

 

[freddy3]

You found a 2 cylinder dwell meter? Where? Got a link?

Click here

Something I just noticed in the earlier pic of your new advance unit - you have the notched retaining ring installed backwards. There's a raised lip around the I.D. of the ring and it should face out .....

Having the ring on backwards may have allowed it to loosen up, letting the locating pin fall out, and allowing the ATU to shift position on the shaft. I would remove the ATU and check that it's still located in the proper spot. You can't tell by just removing the chrome cover, the ATU has to come off.

Sorry, what part is the ATU? Is that the advance unit (weights, springs, plate)?
I remember watching the shop install the (then new) advance unit at the end of last year and I thought that ring (with the arrow engraved on it) only went on one way? Also, if I remember correctly, that ring (with the arrow engraved on it) is flat on both sides (no raised lip).

If forgot to mention that I installed a new condenser today, which had no affect at all.

 

[Gordon]

ATU= advance timing unit. The whole assembly.

 

[freddy3]

Thanks, Gordon.
Not sure about the existence of that "raised lip" on the ring with the engraved arrow tho'?

 

[sgallaty]

Click here

If forgot to mention that I installed a new condenser today, which had no affect at all.

Yeah that won't make a difference unless your old one is shot. If it is you'll see sparks when your points open.

 

[freddy3]

sgallaty: That's what I thought, but it was suggested some time back and I'd picked one up, so.... Oh well....

 

[5twins]

The raised lip is on the notched ring that holds the ATU onto the end of the cam, not the little disc with the lines scribed on it. You can see it in my pic between the 2 yellow arrows and under the spring. See that raised ridge just above the lower yellow arrow? Now look at your pic - no raised ridge showing on the notched ring - because it's on backwards. If the shop installed the ATU then they are the ones who put the ring on wrong.

 

[freddy3]

The lines on the ATU and the backing plate are properly aligned in my photo (I placed the red line just next to the engraved line on the parts so as not to obscure them):