Pros and Cons to Flipping Rear Swingarm Eccentrics

Awesome, thanks Leon

Ok so maybe this is a dumb question but I still gotta ask it. Took at look at mine tonight and then looked at the donor/project 1985 rear eccentrics and they were 180 degrees out from each other, meaning one of them has already been flipped by a PO, but I don't know which one. Here's a pic of each swinger, please let me know which one already has the flipped eccentric and which one is stock?

Donor/Project 85'

Mine:

Thanks for the help gang,
Brett

Since the top pic would put the wheel in the lower position thus raising the bike, that gets my vote.

GPzMOD750 wrote: Since the top pic would put the wheel in the lower position thus raising the bike, that gets my vote.

I believe you are right. After a bit more digging this morning and checking partzilla seems to help confirm it as well. But at 10pm last night when Pops pointed it out my brain was too fried and too tired to work out much more than saying over and over "Hi my name is mud" ala Wile. E. Coyote

Thanks,
Brett

I don't think 3/4-1" would even be noticeable to me. Interesting to see how it handles ether way. :whistle:
Steve

swest wrote: I don't think 3/4-1" would even be noticeable to me. Interesting to see how it handles ether way. :whistle:
Steve

I think you would notice it, small changes make a difference and 1 inch raise/lower on the back end is a big difference, both in seat height and frame castor angle. I certainly advise careful road testing of any alterations, preferably in small increments at a time if you can.

I've raised all my twin shocks, Daveo has lowered his - both of us preferring the change: this is subjective depending on the rider.

Best way to think castor angle and frame geometry is to compare two totally unlike bikes, look at the wheelbase and fork angle differences on a modern hyper sports bike with razor sharp steering but less stability, to a raked cruiser style with long forks and lots of trail that seems to steer itself in a straight line with and is solid as a rock but slow steering into bends.

...slightly off topic but the factory are always making small changes to established designs: IIRC the Lawson reps had 1.5 degrees difference in the frame castor to the GPz1100 models, and revised yokes on the 1000R to alter the bar position and rider weight distribution. Then the later 1100R had the 18 inch front and fatter rims (GPz750 3 spoke unitrack size) again altering everything. The Japanese 'Kaizen' need for continual improvement to any design.

Tyrell Corp wrote:
I've raised all my twin shocks, Daveo has lowered his - both of us preferring the change: this is subjective depending on the rider.

How did you do it without the eccentric? Or did you swap in swing arms with them?

Tyrell Corp wrote:

swest wrote: I don't think 3/4-1" would even be noticeable to me. Interesting to see how it handles ether way. :whistle:
Steve

I think you would notice it, small changes make a difference and 1 inch raise/lower on the back end is a big difference, both in seat height and frame castor angle. I certainly advise careful road testing of any alterations, preferably in small increments at a time if you can.

I've raised all my twin shocks, Daveo has lowered his - both of us preferring the change: this is subjective depending on the rider.

Best way to think castor angle and frame geometry is to compare two totally unlike bikes, look at the wheelbase and fork angle differences on a modern hyper sports bike with razor sharp steering but less stability, to a raked cruiser style with long forks and lots of trail that seems to steer itself in a straight line with and is solid as a rock but slow steering into bends.

...slightly off topic but the factory are always making small changes to established designs: IIRC the Lawson reps had 1.5 degrees difference in the frame castor to the GPz1100 models, and revised yokes on the 1000R to alter the bar position and rider weight distribution. Then the later 1100R had the 18 inch front and fatter rims (GPz750 3 spoke unitrack size) again altering everything. The Japanese 'Kaizen' need for continual improvement to any design.

I'm sure you're correct but I dress out at 240 so it would be different for me. :lol:
Steve