'79 Custom - staying custom...for now (10 year sleeper)

Hey, what projects are you planning or preparing for? CBX, other motos, workshop, WHATEVAH!
daves79x
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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by daves79x »

That sync screw is not linked correctly underneath. Take some more pictures and I’ll tell you more. But they will likely have to come apart to fix. That assembly should be a mirror image of the 1&2 sync screw.

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desertrefugee
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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

Thanks Dave. You're absolutely correct. The thing is, I had taken it apart once to address this and duplicated the incorrect positioning! Third time was the charm. Funny, the other bank went together without a hitch. Must have been getting tired.

But, this just serves to emphasize that the engineering on these babies is precise enough that less than 2mm is enough to completely screw up the geometry.

So, back to our regular programming. I won't likely update on carbs again. It'll be the "next big thing".
'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

My next moment of clarity came during leak testing:
IMG_5834.JPG
I took my time and (with the exception of the above brain fart) things went fairly smoothly. I wanted to make sure there were no Niagra Falls leaks, so I tied up my aux tank and opened the tap. Seemed fine. Tipped left/right/forward/backward ... wait a minute - multiple leakers! Seemed to be coming from the drain tubes. I pulled a couple of screws and the new orings were fine. Torqued them all down. Still leaking when tipping 30'ish degrees. I'm thinking that the bike should never see that kind of angle (during normal operation), but I was a bit bummed.

...until I remembered the standpipe overflow! I knew none of them were cracked, but it spooked me for a bit.
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'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

"The older I get, the more I understand. Don't let the fear of what could happen make nothing happen." - Anonymous

daves79x
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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by daves79x »

You don’t leak test by tilting the carbs all around. Prop them at the approximate angle they are on the bike and let them sit. Then if there are no leaks, test the accelerator pump for proper operation. You did check/set all the float levels also? The o-rings on the drain screws really serve no function other than to prevent gas from leaking out there when you open the screws to drain the carbs. There really is a lot more to these than it may appear.

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

Thanks, Dave. Floats are dead on. Bench synch is as close as I can get it. Fractions of a millimeter. I'm pretty confident that they're ready to go on. Still have few "other" details to tend to. A certain list of recommended actions springs to mind . . .
'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by daves79x »

Again does the accelerator pump work properly?

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

Sorry, forgot to note that I verified accelerator pump operation during initial reassembly. Dang near squirted fuel in my eye. After the bank was together, I verified accel pump shot delivery in each throat. They seem equal.
'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

Yeah, it has been hot already here in the low desert, but the garage doesn't heat up until into the afternoon. So, I'm still making progress. I'm actually putting things back on instead of taking them off. Got the carbs back on today, the Pingel is installed (still need fuel line and filter), and hung the exhaust. Recall this one has had an RC Engineering header with custom pipe for several decades. But, I got the original RC silencers still in the box and never installed. Got them on today, too.

I'm running out of excuses to fire this thing up. I still have bronze swingarm bushings and an All Balls headstem bearing kit to install. I know brakes are recommended, but the PO said all hydraulics were rebuilt just before he parked it. I believe him as the fluid is clear as a bell and actions are firm and solid. I'll hold off on that for bit.

One problem: The RC Eng header has been running on the bike for decades. The silencers are fresh out of the box. Makes the headers look a bit shabby. I may have to spring for chrome. (Probably cost more than a new set of pipes).

Fingers crossed that it'll run well without ugly noises.
IMG_5878.JPG
IMG_5885.JPG
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'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

"The older I get, the more I understand. Don't let the fear of what could happen make nothing happen." - Anonymous

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by Dynamohum »

Good luck with the build. I’d love to see the inside of my float bowls after nearly 70,000 miles as I’m sure they must be dirty. What’s on my side I suppose is that it’s been a running and riding bike for all 39 years. When it really starts using oil I’ll have to get into the motor and then I’ll take a look. Surprisingly the petcock works fine and doesn’t leak and although the inside rim just under the cap looks rusty in color, the inside of the tank is clear. It’s always parked with a full tank (89 octane from Chevron usually) and for any length over a month, also has Stabil or Seafoam. Seems to have worked!

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

Thanks. Fired the bike up this morning. I'd left the petcock (new Pingel) open for several minutes. Sounded good for a bit, but then started starving for fuel. For some reason, the Pingel is not flowing well. I'll be pulling it later today. But, for me, this was a momentous moment. The bike had been sitting for 10 years and I hoped the original owner was being honest in saying it was a good runner. I think maybe it is. It never got close to warming up, but almost idled off the choke - until the fuel began running out.

One last poke in the ribs, it seems. And this was supposed to be an easy resurrection. (It has been, actually).
'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

"The older I get, the more I understand. Don't let the fear of what could happen make nothing happen." - Anonymous

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by daves79x »

Just noticed - you ran the bowl vent lines on top of the rear bracket. They will have to go underneath the scallops. You’ll never get the sync socket in the way they are now. Carbs don’t have to come off. Just take the upper rear brackets off and rotate them down. Sorry.

Those Pingels are tricky. They have a hair-trigger on/off/reserve.

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

Thanks, Dave. Your councel is very timely. The fuel starvatation was simply routing of the filter and lines - not enough slope. But, although the bike seems to be running well, a fair amount of chain rattle at idle tells me it's a bit ragged. So, I'll need to do a synch first off. I have an older Carbtune unit, so I'll be doing the six cylinder shuffle.

I don't even want to mention that the rattle seems to smooth out a bit when choked. Dang, I hope that doesn't mean slow jet restriction. I would be hating life if that's the case. I swear it'd have to wait until cooler weather. I have other pressing obligations - garage and otherwise!
'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

"The older I get, the more I understand. Don't let the fear of what could happen make nothing happen." - Anonymous

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by daves79x »

You've got the typical clutch rattle I'm sure you've read about. It can be mitigated by careful syncing, but all passages must be clear. Do what you can now and see what happens. I'm sure you've heard by now that it usually takes 3 tries to get these carbs right! I'm sure you've also seen the clutch basket fix for the remaining rattle once everything else is right.

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

<<EDIT: Deleting Duplicate. Sorry>>
Last edited by desertrefugee on Mon Apr 16, 2018 8:28 pm, edited 1 time in total.
'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

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Re: '79 Custom - staying custom...for now (10 year sleeper)

Post by desertrefugee »

daves79x wrote:You've got the typical clutch rattle I'm sure you've read about. It can be mitigated by careful syncing, but all passages must be clear. Do what you can now and see what happens. I'm sure you've heard by now that it usually takes 3 tries to get these carbs right! I'm sure you've also seen the clutch basket fix for the remaining rattle once everything else is right.
Dave
I hear you, but I'm not listening! :(

I'll see if I can pop them off before I go into hibernation, but, I'll synch first - and I do have some other items that I need to get done.

Dang it.

I have seen the basket swap mod - and would love to do it. I'm guessing late baskets are getting harder to find (i.e. expensive).

Thanks. I think.
'86 VMax, ‘83 ZN1300-6, ‘78 GL1000, '75 750K

"The older I get, the more I understand. Don't let the fear of what could happen make nothing happen." - Anonymous

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