Ed L. wrote on 12/31/69 at 16:00:10:

It's possible but I don't think so.  The bike really has pretty low mileage and I checked the eye-to-eye measurement of the shocks after removing them and they were 10.5".  Unless the springs are just really wimpy in comparison the heavy-duty Progressives.  Again, this is just with the bike's frame weight, etc... no rider.  The new shocks raise it a lot.  I am happy with the feel and the ride though.  There are just some oddities to be dealt with.  They may settle a bit with a little more saddle time.  Well see.  Either way, I'm satisfied.  I just wanted to put the info out there for anyone considering these so they could make a more informed decision.

It's a flat black rattlecan paint that's supposed to be good to 2000F available at AutoZone.  I think it was called Flame-Proof or something similar... and thanks.

I hate doing it in public for the same reason (especially since my Euclidean geometry is quite rusty) but here it goes...

I used the Pythagorean theorem too.  I didn't measure each leg as I knew both A and B would lengthen to some extent when the hypotenuse (C) was lengthened.  That said, I simply took the difference in the hypotenuse (2") and figured each of the legs would be 1" if it was a right Isosceles (A=B) triangle.  That would mean 1" of additional height.  Since I doubted A and B would be equal, I figured the additional height would be somewhere between 1" and 1.5".

Reelthing wrote on 12/31/69 at 16:00:10:

I took that into account by figuring up to 50% more lift (1.5" instead of the theoretical 1" if A and B had both lengthened equally) I think you're right about A shortening a bit but I still don't see how it's possible to pick up 2.34" in B when C was only increased by 2".

Ok, installed the 11" 90/130 shocks tonight
looks like it results in a 11/16 inch lift over the stock
shock in the 3rd preload setting with the Progressive in the 1st preload and 3/4 inch on the 2nd preload when measured like this .....  


Before the install from the lock to the red mark - about center of the axle measures dead on 11 inches

after the install the same measurement is 11 11/16

I have the preload set to the 2nd click - the 90/130's may be light - the 11" shocks only have about 2" of travel and on the 1st preload my 180lb arse used about 1/2 inch of that - so I went to the second click - packing the span wrench with me case i hit bottom on these back roads - I'll know by the end of the day - the bike stance changes a little but not much.

There is a major difference in the way the bike handles in all cases - tight curves with a little twist on the throttle on the way out, flat road 45mph over less than ideal concret joints road patchs and such. as well as something i didn't expect in the least -75 mph highway speeds - at higher speed it feels far better planted.
It's not that the shocks jump through hoops or do tricks but they eliminate or greatly dampen undesireable bike movement.

The old shocks may have been flat worn out and for the most part  I was riding on springs getting a pogo stick effect far more than I thought as they did have 10 years and >22k miles on them.      

I never moved from the 2nd click on the pre-load as the only time they hit bottom was over a speed bump while sitting down, for my weight and the roads I ride the 90/130lb springs feel about right. Need some more ride time - think I'll spend a week on the 2nd before I try the 1st and 3rd pre-loads.

Really enjoyed day 1 with the Progressive 412-4232c installed and the fancy drilled rotor seems broken in - it's low carbon steel completely zinc plated so it took a few miles for the new pads to sand it down.