Re: 1972 DS7 The Long Road- monoshock conversion done
SONIC. said:
I'm liking this.
I'm putting the same swingarm on my sr500.
What did you figure out about the upper mount?
Your bracket looks about 3x the length of the ex250 bracket, which means that the frame tube and your welds will get 3x the force as the ones on the ex250.
Could you shorten the upper bracket to move the pivot point closer to the frame? What was your reasoning for making it so long? To get the shock as verticle as possible?
Sorry for the 20 questions, just picking your brain before I start welding 8)
No problem on the questions. The upper mount is actually 3" from shock center to center of tube. I did the calculations on the force(psi) that will be appllied at that point and the tubing will be fine. It is well under the yield and tensile strength of the tubing even at 3" of rear shock compression. I can't say if it will be 3 times as much as the ex250 since I don't know the spring rate on that particular shock.
Having the shock at an angle to the upper mount(lever) and not at 90 degress does lessen the actual force that is applied at the pivot point also. Notice how much of an angle the kawasaki mount is at.
I tried to make the upper mount as close to the frame as possible but it is limited by the open area that the shock passes through. This was the shortest that I could get it without the shock spring rubbing the swingarm.
Rundown, thanks for the compliments. This has been a great learning experience for me. I usually quietly read through threads here and on the net, scratch my head, figure it out then do it. I always tell my children that anyone can achieve anything as long as they are patient, willing to listen and go slowly.
I did get the carbs back together, mounted the throttle up, ordered the headlight brackets and got the engine side covers back from the powder coat guy(before he went on a duck hunting hiatus). I figured out the wiring and actually put together a list of OEM wire colors with there service on the DS7/R5. If I get a chance I may post that up..who knows it may help someone else out.
Oh and I ain't going to work tomorrow!