1978K for Resto Mod

[rich]

shinyribs wrote

 How do ya like it? Does it tug on the bars any?

Haven't really ridden it enough to say. I've got windscreens on my DOHC and Goldwing (the one on the goldwing is huge for a handle bar mount) and never noticed any tugging with those.

This one does look like it'll direct the wind right onto my chest though. Probably work better with clipons or clubman bars. But we all know what a pain in the back those can be.  

[shinyribs]

Haha. Yeah, they're bad in some ways, but I find myself missing leaning on a set of clubman's. I need to build something cool.

[rich]

Just got back from a quick ride to town and I gotta say the little fairing does a good job. Builds up a nice little envelope and keeps the wind off my chest. Didn't notice any buffeting of my helmet and was able to maintain a nice relax grip on the bars.

[rich]

Why does thing eat coils? Tried to ride to work today and got about 6 miles and lost two cylinders. This happened last year and I put a set of (cheap) Emgo coils on. Ran fine until now. I swapped in a set of OEM coils from my 77.  Haven't rode it the requisite 6 miles yet to see if one fries. Just wondering if some thing could be killing the coils or did I just go to cheap with the Emgo brand.

[TOOLS1]

I think you have answered your own question here.
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[rich]

I got the coils from vintage 750.com not sure if they were Emgo or not. But they were cheap. I can't think of any reason they'd fry with a stock points ignition. Both times when they went out it was only after a few miles. Once cooled down it ran fine.

[TOOLS1]

Did they mount to the stock frame tabs? The coil mounts act as a heat sink, and dissipate heat to the frame mounts.
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[rich]

That's  the problem. The back of the right  side didn't  attach to the bracket. The wires were in the way.

[TOOLS1]

Cut those wires off.
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[rich]

So I guess it wasn't a problem with the coils. It lost cylinders again! I think it was a bad condenser. I changed the points and condensers. Went out and go it heated up and still running on all four.

But...

I broke something else. It starts missing at about 6,500 RPM and up to the redline. Which sucks, because that's where it gets fun.  I changed the plugs, thinking they may have been fouled by running with no spark on two cylinders from time to time. But that didn't help. Still cuts out at high RPM.

When I put the new points and condensers in I also set the timing. It seemed way to advanced at an idle so I retarded it a little. The book wasn't really clear on the "1 4" marks (when comparing what I could see on the timing plate). After I discovered the high RPM miss, I put the timing back to where it was (closer to the two || marks). It still missed. Runs great up to 6,500 though and idles good.

I used a timing light to set the timing and a dwell meter to set the points. They are about 25 degrees (on the 8 cyl scale), which is what the manual recommends. It goes to full advance around 2,500 RPM, so I guess the advance is working (maybe to well, seems to go full on awful quick).

I'd suspect my coils and plug wires (which are 1977 OEM issue from my spares), but it didn't miss after I changed them when I was having the spark loss problem, so I think they're still good. I don't know. I guess I'll put my new set of coils and wires back on and see if that cures it.

Odd thing is my '79 DOHC does they same damn thing now! Runs freaking awesome, until about 8,000 RPM, then starts missing.

[TOOLS1]

Try setting your dwell to 21* on the 8 cylinder setting.
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[rich]

Does the timing make any difference with this sort of issue? I mean, it (the bike) doesn't seem to really give a crap what I time it at, runs great (up to 6,500).

[TOOLS1]

The timing would not cause a miss. However you time both cylinders to their respective "F" mark. Time 1-4, and then 2-3.
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[rich]

Need to find my test light and just do the static timing method. I only checked 1-4, I see where there's separate adjustments on the timing plate for 2-3.

[TOOLS1]

Static is OK, but a timing light is the way to go.
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[rich]

Timing plate was warped. When I was trying to reset the dwell I noticed a lot of variation at different RPMs.

I had used a small impact to remove the old points. Didn't even think about bending the plate. I'm just paranoid about striping those JIS screws so I always have used and impact driver on them.

Anyway, bent it back until the dwell remained steady throughout the rev range and set them at 21degrees. Runs great again.

Now to find something else to bend, strip, or cross thread.