KZ650 Shock Mount Engineering Question!

Hey got a question here from a very much non-engineering type. I am mounting an 01 SV650 swingarm to my 78 KZ650 but do not plan to mono shock the setup. Rather I want to keep the dual shocks. However being these things as they are...the swingarm is made a bit askew to make room for the sprocket carrier. So although the wheel is center in relation to the pivot point, frame, and front wheel...the shock mounts don't line up evenly on both sides. I made a drawing to illustrate what I mean:

I will post a real pic once I get the sleeve I'm having made to adapt my pivot bolt is done, then I can see exactly where it all lines up.
So, if the right side shock is mounted off to the side of the swingarm rather than centered right over it, would it be a bad idea. From a safety/function perspective? To me it seems that if a sturdy enough mount was tig welded to the swingarm it should be fine. But like I said I'm no engineer, so any opinions or insight would be awesome. Thanks!

Yeah, you should be fine if your bracket has some gussets on it. Also, don't weld much on the side if you can help it. Biggest thing is making sure your shocks are at the same height/length when mounted and that they are going to travel and not bind when compressing.

For the bracket, gusset from the side of the bracket to the top of the swingarm if you can and then have it go down on the side and gusset that way as well to the bracket/swing arm.

What you are trying to do is transfer the load on the shock to the swing arm. If your mount is weak it will snap, hence the gussets. If you weld too much on the swing arm it may weaken it which is why I recommend fewer welds on the side, or to weld in spots, but not full length and not on the corners of the swing arm.

Hopefully you are more confused now then when I started, because from my experience, complicating the issue is the job of engineers :laugh: .

KawiConvert wrote:Hopefully you are more confused now then when I started, because from my experience, complicating the issue is the job of engineers :laugh: .[/quote]

Yup. What he said......

:woohoo:

Haha I like that check:P So, then is this about what you mean for the gusseting and welding?
These drawings are fun to do...

I have not learned to weld yet so I will be taking it to someone who can tig weld aluminum well.
And man, what about figuring out the angle of the swingarm and shocks?

Since the shocks are mounted perindicular to the pivot of the swing arm, it should not matter if you move them laterally. They only apply a force in the vertical plane, as long as the shock is not mounted at an angle (as viewed from the rear).

Ok, that makes sense to me. Thanks for the input. As far as a mount design, would something like I have drawn makes for a sturdy setup? It seems like all the newer mounts I see are triangular. And the gusseting? Can't wait to get my swingarm mounted up to see how off it's really gonna be...just waiting on a sleeve and resized bushings for the bolt.

the way you have that laid out looks like you wont have any problems at all by the way you are a gooder drawwer

The only problem with how you locate you shocks laterally is the effective swingarm travel and the harshness of the suspension.

Shocks mount near the rear axle on the swingarm to allow for a lighter swingarm, without bending in the middle (or wherever someone would mount the shock other than the axle). If you mount the shock near vertical you will have great tuning as the shock moves more for each bump so you can fine tune it, but you will have limited travel as your shock will move the most in this position for each change in swingarm angle.

If you mount the shock at a 45 degree angle the shock moves less which translates into more swingarm travel range, but a harsher ride that is harder to fine tune.

And then yeah, what Bounty Hunter said about aligning them so that they aren't on an angle compared to the travel.

Last thing, the mount looks good, I would only add 2 gussets on the top side as well. This way you can have them welded to the swing arm only at the middle of the swingarm surfaces and still have good strength. The outer edges are where the stresses will be highest, so if you can avoid welding there it will make the design stronger. This will add a few more ounces to the bike, but if you take a bathroom break before riding you'll more than make up for it.

Awesome...thanks for all the helpful suggestions. Convert-I'm thinking that the shocks will end up much closer to the axle my drawing just came out weird.:side: Now to find a competent welder in the Cincinnati area...know any?

Sorry, I tried my hand at welding aluminum for the first time in 5 years today and all I have gotta say is you are not looking for me to weld it:laugh:. Good luck!

I got the pivot point mostly buttoned up. The shock to the right didn't end up sticking out as far as I expected so that's good!Now just to find some decent shock and figure out the angle/placement for the mounts.