Fleeting flying fig - brings a tear to my eye. Actually, I spit beer.That’s because he’s right, and you’re not. Call us angry old men al you like. You ain’t hurting anyone’s feelings here. Quite honestly, no one here gives a fleeting flying fig what yours (or anyone else’s) bike looks like. What we care about is how it WORKS. You made the statement that if you had placed the mount higher up no one would’ve batted an eye. You are correct because that’s where it should be. Raise the front mounting point up above the rear mounting point so you get a more progressive shock compression. Even then you will be somewhat limited by the fact that the shock was designed to utilize a rising rate linkage and only has about 2 inches of total travel. But at least the rear won’t be getting all wobbly and pogo-y on whoever tries to ride it.
The new admins make us play nice now. But had you been here even a year ago, you’d know angry old men. There are some old forum traditions that aren’t so frowned upon, though....,
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That's not what I said. I said had I mounted it vertically from the swingarm to the backbone no one would have said anything. Because that's where it should be? It would take a 25~30kg/mm spring to work there while all of the stress would be concentrated on the arm brace...which is a small and lightly made piece of real estate. And even then I would have had a hard time positioning the shock in a way that would give me full swing and full stroke. Mounting it in the middle of the swingarm to the frame, "where it should be", is quite possibly the worst place to put the shock on this bike. Where I have it I have full travel and it's only going to require a 17~17.5kg/mm spring and the stress is distributed across the entire arm.You made the statement that if you had placed the mount higher up no one would’ve batted an eye. You are correct because that’s where it should be.
Gotta make sure you can put your butt someplace that lets your hands reach the bars comfortably. Stock tank wouldn't work with the forks, have to run a skinny, tall tank, new tank doesn't work with the factory mounts so those gotta go, and when those go so do the seat rails so can't use the factory seat. Just running the forks means none of the body works. It might help to remember that this is a Honda Shadow, not a CB750."nothing except the seat/tank line has been finalized" Modern day priority, start with the bone line, once you got that right all the small things like suspension travel will fall into place.
Such that the loads on the shock are transferred into the frame at an angle that is conducive to the shock absorber and spring operating efficiently. You want to design it to be easy as possible on the shock or you are going to make heat and heat is not good. The shock should be more in parallel alignment with the swingarm so the shock and spring is not operating at a disadvantage.When you say "parallelogram" do you mean with the shock parallel to the arm or adjacent to it?
Well, with the space and suitable locations to mount a shock with an appropriate stroke I have it where the stress on the shock and frame is as low as I can get it without, as described above, building a large cage around the rear wheel and using a shock with an enormous stroke...which I don't have room for anyway. Moving the frame mount side higher to where it's parallel with the arm would only let me use a slightly...and only slightly...lower weight spring while putting a lot more stress on that area of the frame and I wasn't confident I could brace it there to make it stronger. If, in the end, where I have it proves to be too weak a location I have clearance to brace the area from behind. Not to mention, even if I mounted the shock parallel to the arm, the travel would still be regressive. Where it's at now the first inch of wheel travel consumes 7.5mm of shock stroke, and the sixth inch consumes 9mm. If I mounted the shock parallel to the arm, because I can't move the frame side mount any further forward, the first inch of travel would still use the same 7.5mm of stroke while the sixth would consume 8.5mm.Such that the loads on the shock are transferred into the frame at an angle that is conducive to the shock absorber and spring operating efficiently. You want to design it to be easy as possible on the shock or you are going to make heat and heat is not good. The shock should be more in parallel alignment with the swingarm so the shock and spring is not operating at a disadvantage.
How well the suspension transfers shock forces into the frame structure is an entirely different science again.
A traditional cafe racer would be a British motorcycle and what you call a traditional cafe cookie cutter bike is generally an abortion from what I've seen.... this is not a CB750 or some other generic cookie cutter standard bike that already has the basic framework in place to be a traditional "cafe" bike.
Your first point is a bit on the pedantic side but whatever...second point, however, most of what people call "cafe" bikes are meant to be artworks and not actually ridden. They don't even count as motorcycles as far as I'm concerned.A traditional cafe racer would be a British motorcycle and what you call a traditional cafe cookie cutter bike is generally an abortion from what I've seen.
You better hope that is Not the case or something is going to bend and break for sure.... The arm is at a mechanical limit before it can overextend the shock and I'm pretty sure the same will be true before maximum compression.