Nothing Special

Okay, you've got equidistant legs from swingarm pivot to the shock mounts, which will give the stiffest suspension. You're getting the idea. The suspension travel is linear with the shock compression, and the suspension's spring rate can be found using the leverage ratio (force multiplier mentioned above).

Now, if you wanted the loop lower and the shock more inline with the backbone like in your original pic, that could be done with more *math*. You would need to plot a chart of the diminishing leverage, multiplied against the shock's increasing spring force to get the true spring rate. It would be a softer suspension, but playing with spring rates and the geometry can give you something that may work for you.

This is a good project for a spreadsheet...
picked up a triumph daytona 650 shock w/ direct link. has a good deal of adjustment in length, but should allow the top brace to come down a little while maintaining desired angles. can't wait for some time in the shed. I'm not much for spreadsheets always confuses me! :X
So here's the triumph shock


i saw another xs650 that was a tracker setup and had the shock mounting tabs at a 90degree from the top of the top swingarm brace. this is how the shock is mounted in the above picture. With an appropriate thickness mounting tabs would this be sufficient? also allows for a shorter bracing system for the actual top brace.

after i get word on this tab placement, i'll make some thick/solid mounting tabs and solidify the brace mount.

as it is, the attached photo shows the setup as still holding acute angles. good? I'm waiting on my spanner wrench to adjust this shock shorter.


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Just off the top of my head I'd say that'll work. The controlling variable in that setup is the spring, availability of different springs and adjustability. Looks like quite a bit of adjustability there, could even fashion spring spacers if needed. If the suspension is still too soft (from the increasing leverage on the spring), a progressive type would accomodate that. If you google 'spring rate calculator', then with some measurements of the coil, you could find a way to establish what that current spring rate is...
Ok so I'll make the tabs as they are but a bit beefier. I should get that spanner wrench Friday. Should I mount it with shock adjusted to either end or at the middle of the road?
Explain why please. The angle I used in last picture goes along with the angles as two many xbs had told me....90deg or less angles. If you explain Your angle I might see.
Tell me you really don't see how that when the rear axle moves up the rear of the shock moves forward and down actually extending rather than compressing the shock ?



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ok i'll be honest, it took me awhile. but i believe i see it now. the zuniga looks nice. I'm not sure I'm that skilled to pull it off, however.

i currently have the bike a. on blocks and b. the rear swinger is tacked in place to be straight. How do i mount the shock w/ the correct positioning? i figured leave the shock adjusted in the middle as it is so i have room to adjust forward or backward. but should i prepare the suspension with it mocked up? or hyperextend it then mount? preload it in someway?

forgive my ignorance. i am no engineer although i understand that i am attempting to fake one through my build. a bit of work done over the past few weeks. an hour here and there...

mocked up with an angle prescribed by you guys (kop/twomany)


called in some expert consultation



and mocked up a seat to try out the suspension when i get it to be a roller

I laughed about this for awhile after i did that seat...was a front grill for an old space heater. but i'm starting to like the idea. obviously i'll make something more appropriate but i'll idea something up with a removable cover/cushion for longer rides.

took a day of rest to build this

no pictures of the forks but i did replace the seals and dropped in 3" hughes lowering cylinders just last night. still need to oil up and button up the front. I'll drop the motor back in and test the rolling frame out.
dump her completely? or just have the reg/rec outside the bedroom?

Hi Vern,
I'm abandoning this analogy.
You seem to be cutting up a welding tank to make a pseudo oil tank and putting a finned reg/rect inside of it.
OK, now I'm switching to a baseball analogy; three strikes and yer out!
Strike 1) finned things should be in an air flow rather than being sealed up in a can.
Strike 2) That thing is HEAVY Are you building a bike or a battleship? Have you no 22ga aluminum?
Strike 3) IMHO fake oil tanks are an aesthetic disaster.
or , but then again it isn't a fake tank and I hear the original pump is used to prime .

Yeah , heat number one killer of reg/rect . Well that and whoever was the dolt that designed the'80's Suzuki crap electrics but that is another story .

The original was pretty well laid out except for the reg/rect under the battery and I guess where else would you put the coils other than above the engine and under the tank in a virtual oven (like everyone else) . All my nearly stock XS's ended up with the electronic reg/rect under a side cover and the earlier mechanical reg on the backbone ahead of the post and the old rect replaced with a hand built 6 diode three phase bridge behind the battery tray . Actually one of the few things the Brits and H-D got right was placing the back to back Zeners or reg/rect out in front on either the down tubes for H-D or the lower triple for Tr and BSA .....



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then I go and edit while you're ...

neverphucking mind ;-)

most of the late electric bits are near indestructible save for the self canceling turn relay and the perverse lighting module otherwise known as the nondescript black dodad the melts, smokes, sometimes detonates and takes all of your forward lighting with it while on a dark road , in the rain , 20+ miles from home ....