Linkert m74 idle control/throttle plate light leak

[CAP'N BOB]

Ha. Retired after 33 years in the Navy. Married to a great woman. Do not care about making more money to just give to the IRS; I have received so much from so many people and as long as my business pays for itself, pays the insurance, and so forth, I am good. I am paying back what has been taught to me over the years by motorcycle mechanics and repair people--People like Eddie Boomhower, Perry Ruiter, others along the way, and now you, Tom. I truly appreciate what you have to tell me, even when I know you are pimping me, it makes me stop, think. learn and laugh at myself a little, which is always good! :-)

By the way, I had never pressure tested anything, really, until you taught me about the bubble test for the Linkert. My customer has two gas tank halves, of course, right and left, and I decided I could pressure test them using what you had taught me about the bubble test and setting up a regulator with clear hose. Just finished both tank halves, they do not leak. I was wondering how to do that when it occurred to me what you taught me for the intake. With a small adaptation, it worked. Again, you have helped me with something that needed to be done on this old bike. Thank you, Tom.

Bob

[T. Cotten]

:Lemme guess, Bob,..

You've got a real job on the side?

(And single, too?)

....Cotten

[CAP'N BOB]

2006. Yes, it probably does, but, I am the last resort for some of my customers when no-one else will help them, like with this 1948 that came to me in multiple boxes and tubs and not put together, and missing a lot of what was/is needed, and I learn a tremendous amount. As my mentor, Eddie Boomhower, told me, sometimes it is just the cost of an education, and I believe everything Eddie tells me! I break at least even every year (even with a salary) and get to build inventory and buy new tools, so, for me, it does not get any better than that. This is not work for me, it is a passion (or addiction as some would say), and as noted, I get to learn a lot when taking on a project like this one.
Bob

[T. Cotten]

Charity is good! :-)

So how long you been in business, Bob?

Doing charity soon returns it to a hobby.

.....Cotten

[CAP'N BOB]

Charity is good! :-)

[T. Cotten]

Gosh, Cap'n Bob,..

Its easiest to just order a repop of the ""correct"" bracket.

If you think you can fabricate something that's great, but usually trying to save the customer a buck turns out to be charity out of your own pocket,

....Cotten

[CAP'N BOB]

Now, there's a thought, I could make a bracket that fits under that motor mount bolt that would put a different angle on the cable and it would be a spacer and flat washer, taking up space, though that may not be a straight shot in. Hmm. Gotta think about that, but, this way does work. And, since he was foolish enough to ask me to build this for him, he deserves my unique way of restoring! :-)

If the cable is still to come in from the left side, because that makes sense to me, the throttle linkage would need to be different and stick out farther to the front, right? Making a new bracket would be easy, the geometry of the bracket coming into the linkage would need to be maintained to make the cable work smoothly. I had to spend some time designing and shaping the bracket I made to get the cable angle to allow smooth operation of the linkage; no binding.

I wish I could send you the MP4 video I shot (9 seconds), but the platform does not allow MP4 apparently, at least I got a message saying so. I saved it in another format and still could not send it. Anyway, if you could see the video, you would see how smoothly this operates. And, when running the engine, the throttle seems very smooth. You are probably right, if it works leave it alone, though if I could make it a '48 style I would like that. This is an icon, being a first year Pan, and I would actually like to maintain as much of that as I can for him. He did not want me to paint any of it, just make it rideable and as correct as I could. Been a long process, finding parts that he did not bring me, making others, rebuilding the engine from the bottom up, etc. I am getting close, now and would like it finished and safe to ride, that's for sure.

Thank you, again for all of your help.

Bob

[T. Cotten]

That's a common Knuck throttle lever, Cap'n...

And you might notice all of the exposed threads on the top motormount bolt; Early Pan cable brackets take that up, and they clamp the sheath.

But pleasing the customer comes first, and all of the "correct" hardware would nickle-dime him sorely.

So you might as well leave it alone if it works!

....Cotten

[CAP'N BOB]

Not sure I can send a video, but if I can, I just shot a video of using the throttle, opening and closing. Works smoothly and when the bike is running it works smoothly. Nope, says I cannot upload an MP4 video. Are there any I can? The 9 second video shows how smoothly this works, but hopefully the still photos will also show it. The stills make it look like the cable hits the top motor mount, but it does not hit. Clears all the way through the process and I left about 1/2" clearance where the wire comes out of the sheath to the linkage.

I remembered part of why I did not like the cable coming in on the right side, the bend coming out of the handlebar seemed too sharp and I think the way I ran the cable there is less stress on the cable. Not being a Factory engineer (or any other kind of engineer), I could be wrong, but then, I also did not like the brake lever on the left, so moved it to the right. Seemed pretty unsafe to me to have to clutch, brake and hand shift, almost at the same time. I have NEVER ridden a tank shift bike, so I may be wrong on that. Time will tell, since I will need to at least test ride this bike before giving it back to the owner. He wants me to ride the first 50 miles of the engine rebuild, but, again, time will tell if I am willing to do that..

Hope these help.

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[T. Cotten]

Its really hard to tell from your pics, Cap'n,...

But it looks like you have the swivel "cable block" butted up against the control wire sheath. You will want good clearance, as both sheath and wire will flex.

The stop limit for both open throttle and idle must be the carburetor throttle lever "tower":

image_31592.jpg

I cannot discern if you have the correct throttle hardware, which makes it all easier;
Note that this one has the swivel in the wrong hole (as well as missing a washer, and farmer wire instead of a cotter pin.)

....Cotten

[CAP'N BOB]

That makes sense now, since even though the hand grip is pulled, the throttle plate is pushed open, so my running the cable in left side of the bike versus in on the right side would not have mattered, it would just have taken a different linkage, probably. I could not find a way to make sense of the cable coming in on the right side, but could make sense of it coming in on the left side with this bracket. As I have said, I normally do not do "restorations or rustorations" and have learned a lot and gained a much greater respect for people who keep these old bikes stock and running. It has been interesting.
Thank you.
The customer is not difficult, I am, due to lack of knowledge and spending a lot of time learning!

[T. Cotten]

.... I was having trouble making any stock-like parts work. The throttle is a push throttle mechanism and my customer wanted a pull throttle, which I could accommodate by coming in from the left side the way you see it.

I'm a little confused, Cap'n,..

Whether the control spiral is the early one that pushes the wire (proper for a Pan Linkert),

..or the late one that pulls the wire, the twist of the wrist is the same for the rider.

Sounds like a difficult customer.

....Cotten

[CAP'N BOB]

20210818_173738.jpg20210818_173749.jpg20210818_185435.jpg20210818_185439.jpg20210818_185443.jpg I made the part and powder coated it. I was having trouble making any stock-like parts work. The throttle is a push throttle mechanism and my customer wanted a pull throttle, which I could accommodate by coming in from the left side the way you see it.

[BigLakeBob]

Glad you got your carb issue under control. In your first picture is that a screw going into the rocker cover to hold the throttle cable? Never seen that before. Leak waiting to happen and future tightening failure, something has to be better. Reverse the clamp and move it to the top motor mount or get the correct oem parts?

[CAP'N BOB]

Hey, Tom. I must confess, I gave up and had someone rebuild the Linkert who does that for a living. I did get the clamps you told me to get, and did use the leak tester I made. No air leaks. Hooked up with the new clamps. Set the timing with the mark as you see in the one photo, per my old Harley service manuals for 47 and back knucks and the one for 48 up pans. Fired it up, last night and can control the idle with the throttle and minor adjustments with the needle. Tested the cold starting cycle again this morning, ran it until it was warm, shut it off and started it with the warm starting cycle. Started on one kick with the warm cycle, had to kick it 3 times with the cold. I know it will take some adjusting.
Still over-oiling, even though I put the cast D-rings on. Need to chase that, of course. Oil goes back into the tank with no issues, but somehow it is leaking at the pans.
Thank you for your help. It felt good starting that, last night and having it idle down and let me adjust it without it dying, and again, this morning. You taught me a lot about this carburetor. I think, I can rebuild one myself now and feel confident.
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