Sonics vs Progressives

[timsatx]

I plan on overhauling my front end. I know the oil needs to be changed so I am going to take it apart, put in new drain holes, and put it back together. I am trying to decide which springs I might want to get. What is the prevailing thought on the springs and what are the differences that might drive the decision?

[connie_rider]

I have the Progressives which used to be what most used.. But I think the current favorite is the Sonics.

If you decide on the Sonics, I have a new set in the garage. (1.1 I think) Mebbe we can work out a deal?

Ride safe, Ted

[kzz1king]

So how do you like the progressives? Are they a big improvement over stock? The bike I just bought came with a new set in the box.
Wayne

[Summit670]

I was wondering the same thing, which springs are preferred.  I thought I saw somewhere that one had to add spacers to one of them, maybe both brands (not progressive).

I've got progressive now, but have had for at least 15 years.  Maybe they are getting soft but I still run about 10# of air (1987 model) because I like a firmer ride and for the front end to sit higher.

[T Cro ®]

So how do you like the progressives? Are they a big improvement over stock? The bike I just bought came with a new set in the box.
Wayne

The Progressive branded progressive spring is better than the stock spring but not by much at all as it still allows for far too much brake dive or rapid compression under big bumps in the road. The Concours is a big heavy girl and her smaller sized front end takes a lot of abuse and in my opinion is better served with straight rate springs, reasonably light weight oil, perhaps enlarged damping holes or better yet tuned with Cart Emulators, also be sure to not put in too much fork oil as too high of a level will make her ride harshly due to over compression.

[George R. Young]

I think Ma Kawasaki put in soft, dual rate springs to compensate for the damper rod's harsh compression damping.

Sticking in stiffer springs, either constant rate or 'Progressive', may reduce brake dive, but it will make the overall ride harshness worse, because what you feel when going over a bump is the sum of the spring compression force and the compression damping force.

The way that makes sense for me is cartridge emulators, for compression damping that's less harsh, coupled with stiffer springs to better control wheel motion and dive. In fact, I installed emulators first retaining stock springs, looking for increased comfort. Only later did I replace with 1.0 kg/mm Racetech springs for better road holding in bumpy turns.

[jim snyder]

I put progressives in mine and took them back out within two months and sold them. They were slightly better
than stock but still had way too much brake dive. Went back with the Sonic 1.1's and still satisfied with them.   

[cmoore]

I have the Sonic 1.1's. I put 'em in about 4 years ago and have been very satisfied with them. Much smoother ride and better handling. A little stiff at slower speeds but I don't care about that. The stock springs were crap.

[Steve in Sunny Fla]

 I ran sonics, but then learned to cut the stockers to get the exact ride I wanted. it's easy to do, just cut about 4" from the tightly wound end, flatten it on a bench grinder, and then install a 1.25" washer and a 4" length of PVC. If that's still to soft, clip another inch off. Easy and basically free. Steve

[kzz1king]

That is what I had done on my 86 Steve and liked it. My 01 came with the progressives but they are not installed. I have to look to see how they are wound but has anyone cut/spaced these? If I can't get a few bucks for them I may as well do something with them.
Wayne
PS I am sure we have similar roads as Florida. Lots of straight miles and the curves are generally long.

[timsatx]

I have the Progressives which used to be what most used.. But I think the current favorite is the Sonics.

If you decide on the Sonics, I have a new set in the garage. (1.1 I think) Mebbe we can work out a deal?

Ride safe, Ted

Thanks Ted, I will keep that in mind. It will be at least two or three weeks before I decide. I have a list of things I need to do to my bike. The forks are one. I also have to give it a tune-up and probably even work on the carbs.

[Cholla]

I've been waiting on jokes aout a hedgehog (not Ron) and an overly made up gal selling insurance.
I liked Progressive springs with 15 wt. oil.

[SmokinRZ]

I have progressive springs.  I liked the smooth ride of the stockers but the brake dive was crazy.  I weigh 180 and wanted a smooth ride, plus I had progressives in my previous concours so I knew how it would ride.  Cutting the stockers would probabaly accomplish the same thing.         

[elvin315]

I plan on overhauling my front end. I know the oil needs to be changed so I am going to take it apart, put in new drain holes, and put it back together. I am trying to decide which springs I might want to get. What is the prevailing thought on the springs and what are the differences that might drive the decision?

Read the SUSPENSION FAQs for a comprehensive overview of fork upgrades.
http://www.zggtr.org/index.php?board=27.0


This one briefly reviews the options. The other articles go into more details.
http://www.zggtr.org/index.php?topic=653.0