which oil to use with Progressive fork springs?
Cruiser
Joined: Apr 2007
Posts: 245
Likes: 0
From: Denver Colorado
RE: which oil to use with Progressive fork springs?
Thanks Charley,
I am clear on the jacking process and the idea of removing the weight off the springs, as the manual is very clear about that... My concern was that it looked like measuring process for determining the fluid level was dependent on on the fork tube being vertical not at the installed rake of the bike... But your idea of measuring before draining the oils is a good one, as the tilt of the rake will be the same, so the fluid level (if done correctly at the factory) could be determined by using the FOL-1...
For those of you interested in the Race Tech valve for your Nightster (not listed on their website) I have sent them some mail asking if the valve is also designed for the 1200N... Guessing it will work as I believe that the 1200N shares the same fork as the 883L which is listed...
I am clear on the jacking process and the idea of removing the weight off the springs, as the manual is very clear about that... My concern was that it looked like measuring process for determining the fluid level was dependent on on the fork tube being vertical not at the installed rake of the bike... But your idea of measuring before draining the oils is a good one, as the tilt of the rake will be the same, so the fluid level (if done correctly at the factory) could be determined by using the FOL-1...
For those of you interested in the Race Tech valve for your Nightster (not listed on their website) I have sent them some mail asking if the valve is also designed for the 1200N... Guessing it will work as I believe that the 1200N shares the same fork as the 883L which is listed...
Road Warrior
Joined: Jun 2005
Posts: 1,334
Likes: 2
RE: which oil to use with Progressive fork springs?
thanks for the input... i was told by a harley tech that the springs in our sporsters were also progressive in style and that there wasnt much difference between them and the company PROGRESSIVES
In theory you could cut down your stock fork springs to accomplish what the progressives do, but I would just buy the progressive fork springs unless you're broke and know how to properly cut springs.
I'd recommend using the Progressive springs, but take it a step further and add in the Race Tech cartridge emulator valves. They'l allow you to fine(r) tune the forks' compression damping and you can use the fork oil weight to fine tune the rebound damping.
Cruiser
Joined: Nov 2007
Posts: 169
Likes: 0
From:
RE: which oil to use with Progressive fork springs?
ok,
I have the progressive springs and was just made curious if I should look into the valves...
anyone else have experience, there are 2 guyson different sides of this fence?
would race tech state not to use progressive due to it being not their product?
is there anything engineered that would effect the use of the springs function or cause imminent catastrphe if the 2 were combined?
does anyone work for a stealer or indepandant that can chime in here?
I would like to know more about this option or why not to consider the 2 as an option together, thx people!
I have the progressive springs and was just made curious if I should look into the valves...
anyone else have experience, there are 2 guyson different sides of this fence?
would race tech state not to use progressive due to it being not their product?
is there anything engineered that would effect the use of the springs function or cause imminent catastrphe if the 2 were combined?
does anyone work for a stealer or indepandant that can chime in here?
I would like to know more about this option or why not to consider the 2 as an option together, thx people!
Road Warrior
Joined: Jun 2005
Posts: 1,334
Likes: 2
RE: which oil to use with Progressive fork springs?
would race tech state not to use progressive due to it being not their product?
is there anything engineered that would effect the use of the springs function or cause imminent catastrphe if the 2 were combined?
is there anything engineered that would effect the use of the springs function or cause imminent catastrphe if the 2 were combined?
No, failure would not happen mixing progressive suspension springs and race tech emulators. The suspension quality will just decrease compared to if you went with an all race tech package.
You are welcome to try your own combinations, but my opinion is that race tech knows their stuff so I would listen to their advice.
Road Warrior
Joined: Jun 2005
Posts: 1,334
Likes: 2
RE: which oil to use with Progressive fork springs?
From their FAQ page:
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.
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.
Thread Starter
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Tourer
Joined: Sep 2006
Posts: 422
Likes: 1
From: Northern NJ
RE: which oil to use with Progressive fork springs?
I'm glad somany continued writing their thoughts and ideas regarding the topic I started the other day, but I
must say, I'm almost more confused now then ever........ lol
I still may just buy the Progressive Companies , progressive fork springs and use either harley regular weight, or possibly this Belray 15w stuff... not sure on the oil as of yet....
I did however write to the progressive people and ask about which oil they recommend, and am awaiting their response..
I hope that I'm making the right choice here...
regards,
JD
[IMG]local://upfiles/17455/65C4CA4C62E74023824A107FF7D0E171.jpg[/IMG]
must say, I'm almost more confused now then ever........ lol
I still may just buy the Progressive Companies , progressive fork springs and use either harley regular weight, or possibly this Belray 15w stuff... not sure on the oil as of yet....
I did however write to the progressive people and ask about which oil they recommend, and am awaiting their response..
I hope that I'm making the right choice here...
regards,
JD
[IMG]local://upfiles/17455/65C4CA4C62E74023824A107FF7D0E171.jpg[/IMG]
Road Warrior
Joined: Jun 2005
Posts: 1,334
Likes: 2
RE: which oil to use with Progressive fork springs?
Ok, here is the breakdown.
Use progressive suspension parts if you want a good ride for a great price. Overall, the progressive suspension package (rear shocks/forks) are provided at a great price and improve greatly over the stock suspension.
Use the Race Tech suspension if you want a premium riding bike. The parts from Race Tech cost significantly more over progressive suspension parts, but provide an even better ride. They are, however, still less expensive than parts from other suspension companies like ohlin and works performance.
Use progressive suspension parts if you want a good ride for a great price. Overall, the progressive suspension package (rear shocks/forks) are provided at a great price and improve greatly over the stock suspension.
Use the Race Tech suspension if you want a premium riding bike. The parts from Race Tech cost significantly more over progressive suspension parts, but provide an even better ride. They are, however, still less expensive than parts from other suspension companies like ohlin and works performance.
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Tourer
Joined: Sep 2006
Posts: 422
Likes: 1
From: Northern NJ
RE: which oil to use with Progressive fork springs?
One last thing..... are the 440 shocks all the same .....As far as year built.... whether they are2007's 2008's ....that kinda thing...
ANYONE KNOW ?? IS THIS A CONCERN?
ANYONE KNOW ?? IS THIS A CONCERN?
Elite HDF Member
Joined: Jun 2006
Posts: 3,572
Likes: 5
From: Templeton California
RE: which oil to use with Progressive fork springs?
I have not much to add except that I have the Race Tech straight rate springs and thier "Gold Valve" cartridge emulators on my other bike, a 2000 Suzuki SV 650 they made an already decent handling bike into a great handling,Ducatti thrashing canyon shredder.They are quite a bit more complicated to install than the Progressive set up though which is why I'm going with that on my Dyna.One thing to remember about the cartridge emulators is that you have to disassemble the forks to make an adjustment to them I don't know about the rest of you but I only want to do that once.So unless your Duck hunting in the canyons probably not worth it.