Triumphrat

rodneybrown · 02-01-2004

Anyone tried Hyperpro continuous changing rate progressive fork springs or shock springs? If so, how did you like them? They kinda sound like snake oil but the few guys I know that have them say they are great. Then again guys who do suspension from the old school say they are snake oil Just like to find some real experience.
Thanks

rodneybrown · 02-01-2004

Anyone tried Hyperpro continuous changing rate progressive fork springs or shock springs? If so, how did you like them? They kinda sound like snake oil but the few guys I know that have them say they are great. Then again guys who do suspension from the old school say they are snake oil Just like to find some real experience.
Thanks

MickMaguire · 02-02-2004

This may help a bit, it's from the race tech FAQ:

Q: I have heard of progressive springs and this concept makes sense to me. Why does Race Tech recommend Straight Rate Springs for forks?

A: When setting up the spring forces in a bike you want a setup that is progressive enough yet not too progressive. A setup that is not progressive enough will have a tendency to feel too harsh yet when a big hit is encountered bottoming occurs. A setup that is too progressive will either drop through the travel feeling mushy and then feel as though it hits a wall or can feel good until it hits that wall. On front forks there are two forces we consider to be "spring" forces. First is the coil (mechanical) spring and second is the force due to air pressure and oil level. Even if you run zero air pressure the oil level causes the pressure to increase as the forks are compressed. By its very nature this increase in pressure is very progressive. We have found that in combination with a straight wound spring we have a good level of progressiveness. If we want more progressiveness we simply raise the oil level.

Anolther subtle benefit of straight wound springs is that they are easy to understand. In order to make sense of progressively wound springs you really have to map out the force as you compress the spring. For example a spring marked 20/40 lb/in (excuse me for the SAE units but this will work with metric units as well) may start out at 20 lbs/in in the first inch but where does the 40 refer to? It might be referring to the rate in the 4th inch or it could be referring to the rate in the 6th inch. This would cause a huge difference in ride.

MickMaguire · 02-02-2004

This may help a bit, it's from the race tech FAQ:

Q: I have heard of progressive springs and this concept makes sense to me. Why does Race Tech recommend Straight Rate Springs for forks?

A: When setting up the spring forces in a bike you want a setup that is progressive enough yet not too progressive. A setup that is not progressive enough will have a tendency to feel too harsh yet when a big hit is encountered bottoming occurs. A setup that is too progressive will either drop through the travel feeling mushy and then feel as though it hits a wall or can feel good until it hits that wall. On front forks there are two forces we consider to be "spring" forces. First is the coil (mechanical) spring and second is the force due to air pressure and oil level. Even if you run zero air pressure the oil level causes the pressure to increase as the forks are compressed. By its very nature this increase in pressure is very progressive. We have found that in combination with a straight wound spring we have a good level of progressiveness. If we want more progressiveness we simply raise the oil level.

Anolther subtle benefit of straight wound springs is that they are easy to understand. In order to make sense of progressively wound springs you really have to map out the force as you compress the spring. For example a spring marked 20/40 lb/in (excuse me for the SAE units but this will work with metric units as well) may start out at 20 lbs/in in the first inch but where does the 40 refer to? It might be referring to the rate in the 4th inch or it could be referring to the rate in the 6th inch. This would cause a huge difference in ride.

02-02-2004

Mick,
Thanks for the response.

I have read the Race Tech, as well as the HyperPro stuff till my eyes have crossed. Also have read other theorhetical stuff and things by old time suspension tuners. Most of it pretty much makes your head hurt. What I do know is Honda and other manufactures are going to rising rate progressive springs in newer models or so I've been told. Also, Race Tech is talking about a dual rate not a rising rate spring which is kind of the norm from the straight rate guys. I have three cases of "they are great" from an ST1100, FZ1 and VFR but no Triumphs. By the way the stock ST spring is a "progressive", really dual rate and so are other bikes too like the Concours. It's just not a selling point to the marketing people. My point is that I'm trying to separate the claims from what actual riders have found.
Rod

02-02-2004

Mick,
Thanks for the response.

I have read the Race Tech, as well as the HyperPro stuff till my eyes have crossed. Also have read other theorhetical stuff and things by old time suspension tuners. Most of it pretty much makes your head hurt. What I do know is Honda and other manufactures are going to rising rate progressive springs in newer models or so I've been told. Also, Race Tech is talking about a dual rate not a rising rate spring which is kind of the norm from the straight rate guys. I have three cases of "they are great" from an ST1100, FZ1 and VFR but no Triumphs. By the way the stock ST spring is a "progressive", really dual rate and so are other bikes too like the Concours. It's just not a selling point to the marketing people. My point is that I'm trying to separate the claims from what actual riders have found.
Rod