sportracer07
New Member
So im getting ready to order the correct weight fork springs for my 95 cbr f3. But im confused about whether to get linear or progressive springs. Im just using the bike for track days.
progressive or linear springs
- Thread starter sportracer07
- Start date
Definitely linear. Shock linkages make it progressive enough.
And Joe, I know why, but don't feel like typing. Lol.
And Joe, I know why, but don't feel like typing. Lol.
sportracer07
New Member
Joe Vital, im assuming so you can control the valving better but thats just a quess. Why is it preferred on the track?
Someone once took 30 mins to explain to me how awesome progressive springs were. Then I had my bike setup by a real suspension pro. Lesson here is ... dont let some loser talk about suspension parts for 30mins cause youll never get that 30 mins back!
Straight rate! Street, track, or dirt.
Straight rate! Street, track, or dirt.
Motofun352
Control Rider
Progressive springs are used to compensate for wide variety of dynamic forces that a manufacturer might encounter with a particular bike and riders that could weigh a little too a lot. Your track bike is specific to you and your weight....as long as you don't vary much a straight rate will allow full use of the available travel without changing (much) over that travel. Makes the bike's response more linear and easier to ride. If you're bottoming out the springs you need stiffer springs, not progressive springs......
sportracer07
New Member
Linear it is then lol. Has anyone ever used Sonic springs?? Are they good quality?
Joe Vital
Member
This answer requires you understand the difference between a progressive and a straight rate spring. As well a basic understanding of what sag is and why we want it on our race bikes.
We set sag to determine the proper ride height of the motorcycle. We do this by adjusting the spring preload using spacers for gross adjustments and the preload adjuster for finer tuning. If you understand how a spring functions and accept they are only used to hold the bike up at a proper height it may be obvious why we use straight rate springs.
Try to imagine how your bike would ride/handle having only springs or what would happen if you had only damping and no springs. The damping, compression and rebound, controls the movement of the spring to ensure the tires remain in contact with the road.
The easy answer is setting the correct sag on a progressively would spring is impossible. Why? For any given spring rate you will need to have a specific amount of preload on the spring to get the recommended sag setting. A progressively wound spring has a different rate for each increment of movement. If the spring rate changes for every increment of movement it will require a different amount of preload for each of those changes in rate.
Hope this helps.
Joe
We set sag to determine the proper ride height of the motorcycle. We do this by adjusting the spring preload using spacers for gross adjustments and the preload adjuster for finer tuning. If you understand how a spring functions and accept they are only used to hold the bike up at a proper height it may be obvious why we use straight rate springs.
Try to imagine how your bike would ride/handle having only springs or what would happen if you had only damping and no springs. The damping, compression and rebound, controls the movement of the spring to ensure the tires remain in contact with the road.
The easy answer is setting the correct sag on a progressively would spring is impossible. Why? For any given spring rate you will need to have a specific amount of preload on the spring to get the recommended sag setting. A progressively wound spring has a different rate for each increment of movement. If the spring rate changes for every increment of movement it will require a different amount of preload for each of those changes in rate.
Hope this helps.
Joe
HondaGalToo
Control Rider
Thanks for the explaination, Joe! Makes sense, also makes me think I wouldn't want progressive springs on a street bike, either...although maybe not as critical.
Joe Vital
Member
Judy, on a street bike they may provide a 'better' ride, more comfortable. I *think* the reason folks started using them was to mask issues with damping circuits that were woefully inadequate. But that is just a guess. They could mask a horrible compression circuit by becoming stiffer as the fork compressed, but then one would need a progressive rebound circuit to contend with the regressive spring rate as the fork returned to normal ride height. It is a mess to just to think about it.
In short; modern bikes don't need them. (Maybe the old crates didn't need them either?)
There was mentioned in a previous post that the rear suspension links on modern bikes provide a similar effect as the progressive spring. I always though the links provided a progressive length of travel. It allowed the use of a shorter shock in order to get a reasonable amount of rear wheel travel in a small package.
Someone who knows sort me out on this?
Joe
In short; modern bikes don't need them. (Maybe the old crates didn't need them either?)
There was mentioned in a previous post that the rear suspension links on modern bikes provide a similar effect as the progressive spring. I always though the links provided a progressive length of travel. It allowed the use of a shorter shock in order to get a reasonable amount of rear wheel travel in a small package.
Someone who knows sort me out on this?
Joe
gixxercurt
New Member
Despite the majorities opinion I prefer progressive springs at tracks like Rd Atl and Barber. It just feels better to me at the bottom of the stroke. For General application just straight rate spring.
mark1200
New Member
seems to me that at the bottom of the stroke the progression is long gone. they r not usually progressive all the way trough the spring, just at 1 end, say about 1/3rd. the reason (to my understanding) is to give u a softer ride over the small bumps on the road. after the spring compresses past 1/3rd it becomes inlier. so at the bottom of the stroke it is at its stiffest area.