The Free "B", a 1971 resto redux

[gggGary]

it's possible they created a run on them.
I bought a set of 10 lol.
The fat set on madness is still going strong I've prolly had the covers off 10 times? Those fat ones eventually shed a bit of "squeeze out" but they just keep sealing. after all those times the gap is now minimal. I think it was @5twins that "found" the amazon ones.
The original vendor drastically changed prices on me, that and the amazon ones why I stopped selling them. Was fun while it lasted, musta been near a 100 sets went out all around the world.
Still have the lathe fixtures to change non o-ring to o-ring type.

 

[Wagner73]

I see you are now using a different size, these:
https://www.amazon.com/uxcell-Flexible-Silicone-Sealing-Gasket/dp/B008MKWE04
I assume these are a better fit?

Amazon is by far the best deal (not including Ali Express which has them super-cheap), but is currently out of them, . Maybe people reading this forum bought all of the Amazon ones?

Ha ha, yes...I bought a pack of 10. Don't need 10, so if you'd like 4, they're yours.

 

[DogBunny]

Thanks for the offer. I'll need a few sets, so will probably buy from Ali Express.

 

[Jan_P]

Seals and O rings are standard elements in Machinery ( Mostly ) The place where these are used is not a complicated . Situation besides
heat
I Would believe they can be bought over the Counter from an industrial supplier As most likely Yamaha have done
OK It can be different in the US Using Inch but Maybe can be found after all.

 

[DogBunny]

I Would believe they can be bought over the Counter from an industrial supplier

Yes, metric or inches. But, expensive bought over the counter or from industrial suppliers. Much cheaper on Amazon or Ali Express. No rush here, I can always find something else to do while I wait for them to arrive. Ali Express from China, with ridiculously cheap or free shipping has gotten really fast, typically arriving in 10-14 days. That's like the blink of an eye to me.

 

[gggGary]

silicone is key here.

 

[DogBunny]

This is the formerly stuck motor from the "win some, lose some" XS1B that I rebuilt a little less than a year ago, and which has been in deep storage ever since. That seems like another lifetime ago.
This is exactly what the intake balance tube assembly looked like from the factory. Unusual hose clamps, and an essential hidden spring inside the tube to prevent collapsing. The tube WILL collapse otherwise. I think the spring on the outside is more about keeping the tube from contacting the hot engine.


In a post by Gary, he recommended using auto parts store heater hose, so that's what I'm using on the Free "B". I never discard springs, and I found the perfect diameter spring for inside the hose, just needs trimming. Looks like a throttle return spring for a V8 to me.
It's taken my entire life to finally learn that worm-gear hose clamps suck at smaller diameters. I always thought that "constant tension," or "constant pressure," or "spring clamps," like above were cheap and junky, but that's completely wrong. They are especially recommended in situations subject to extreme thermal cycling.


I didn't like the fit of the heater hose, so I added heat shrink to the nipples. That helped.


End result. I still didn't like the hose fit, so I took it all off and added another layer of heat shrink to the nipples. Done.

 

[DogBunny]

Two of the four M6 holes that hold the intake manifolds on needed Helicoils. One was an outboard hole, no problem there. The other was an inboard hole. No room for a drill motor.
I very much did not want to pull the engine. So I bought the above 90 degree attachment for $20. (Harbor freight also sells one for $20 that is even more compact, but which looked flimsy to me.)


There is just barely enough room between the engine and frame using a drastically shortened drill bit.


Next up was tapping the new hole. My T-handle tap holder was way too big. My adjustable tap wrenches were also too big -- one handle is removable, but the other is fixed. So I took an adjustable tap wrench from a cheapo tap and die set, removed the one handle, and cut down the fixed handle.


Finally, my M6 Helicoil installation tool was too long. I made a short tool from a M6 bolt by shaving down the threads and making a slot for the Helicoil tang.
See how short the drill bits needed to be. Always interesting trying to get a 2-flute drill bit with no shank to spin true in a 3-jaw drill chuck. I suppose some of you could have saved some of the shank, cut down the fluted end, and then sharpened it. I'm not clever enough to sharpen drill bits.

 

[gggGary]

I'm not clever enough to sharpen drill bits.

sure you are! + don't take much for aluminum...

 

[Jim]

Where there's a will.....
Well done William!!

 

[Mailman]

Re: that balance tube for the intake. Do you guys think it ever did any good? The factory was quick to delete it. I’ve always liked all the unique little quirks of the early models.

 

[DogBunny]

sure you are! + don't take much for aluminum...

Quite right. Truth is, cutting and then sharpening never occurred to me until I wrote that post. I'll do it next time.

Re: that balance tube for the intake. Do you guys think it ever did any good? The factory was quick to delete it. I’ve always liked all the unique little quirks of the early models.

The consensus seems to be that it probably doesn't do enough to worry about. Some people just cap off the nipples.
My opinion is that it can't hurt, and I too like the quirky differences of the early models.

 

[gggGary]

Three quirksters in a row...............
Kinda wonder what size heater hose thought I remember using a heat gun to get it over the nipples..

 

[DogBunny]

Three quirksters in a row...............
Kinda wonder what size heater hose thought I remember using a heat gun to get it over the nipples..

I guess I blew it on this one. Somehow, I thought that 1/2" was the smallest bulk heater hose size, so that's what I bought.
Wrong. 3/8 is the smallest.
1/2" = 12.7mm
3/8" = 9.5mm
It would make sense that I had to sleeve the nipples with heat shrink to make 1/2" work, and that you had to use a heat gun to make 3/8" work.

 

[DogBunny]

Not a super-important item, but the original 70-73 seat prop is another engineering fail. It's awkward, takes two hands to open the seat, two hands to close the seat, and does not hold the seat very secure. If the hook slips, the seat will bang into the right side cover. They never used it on any other models.

In the past I tried replacing the hook with a tie wrap, which works great for about a day until the tie wrap breaks. I considered a stainless steel tie wrap, but had a hard time envisioning it folding out of the way properly when I closed the seat.

The solution is a chain. Bought some mini-shackles on Ali Express. The twist-link chain is from an old dog leash (I had a dog that could instantly bite a leather or nylon leash in half). Just 5 links. Works excellently.

Seems like I've been working on this bike forever, but it hasn't even been two months. Getting dangerously close to finishing...

 

[Jim]

but the original 70-73 seat prop is another engineering fail. It's awkward, takes two hands to open the seat, two hands to close the seat, and does not hold the seat very secure.

The baby RD (RD200) uses the same messed up system.
Been ponderin' how to mod it.
I like your idea! Might steal it or do a riff on it using stranded cable.

 

[DogBunny]

The baby RD (RD200) uses the same messed up system.

Interesting. I looked at the 1972 CS5 parts diagram, and it shows a standard bent-rod seat prop???

 

[Jim]

Yeah, it's the rod type. Problem with it is it opens up too far. There's a notch pressed into the set pan to give clearance for the right shock. It doesn't. Where that notch meets the stud, it chewed up the old seat cover. The way it was set up, there's noting to prevent "over" opening the seat and doing the same thing to the new cover. I want something that positively stops the seat before it contacts the shock.

 

[DogBunny]

If you use a cable to limit how far the seat opens, will the cable behave and fold in an agreeable way when you close the seat? The chain collapses and retracts in on itself very nicely.

 

[Jim]

Dunno... Haven't got beyond the first (mind only) draft yet.