Progressive fork spring install

Triumph makes a pump that adjusts the oil level, but it doesn't drain the fork. Silly, I know, to go to the trouble of having a special tool that sucks out oil rather than just making a drain at the bottom. Just like Flip, I see little things all over that could have been handled during manufacturing for mere pennies more. I suppose all those pennies add up in the long run and "do-it-yourselfers" are fewer than we think. To a shop with space and equipment, removing the forks to turn upside down isn't that big of a deal ... but from an owners maintenance point of view it's more work we just aren't willing or able to attempt unless we have the time and ability. That probably keeps dealers service depts busy.
 
Triumph makes a pump that adjusts the oil level, but it doesn't drain the fork. Silly, I know, to go to the trouble of having a special tool that sucks out oil rather than just making a drain at the bottom. Just like Flip, I see little things all over that could have been handled during manufacturing for mere pennies more. I suppose all those pennies add up in the long run and "do-it-yourselfers" are fewer than we think. To a shop with space and equipment, removing the forks to turn upside down isn't that big of a deal ... but from an owners maintenance point of view it's more work we just aren't willing or able to attempt unless we have the time and ability. That probably keeps dealers service depts busy.

A turkey baster works just as well.

It's not just Triumph (that deleted the drain plugs), it's all the manufacturers.

USD forks cost less to make because there are fewer parts but they are exponentially harder to maintain.

Problem is, if you 'suck' out the fork oil (if you could, you can't because the valving is in the bottom of the leg, so you can't get to the bottom anyway), you'd leave all the crud in the bottom of the fork leg anyway. So you remove the legs (after taking apart the front end), loosening the triple clamps, removing all the junk attached to the forks, and invert them....and you still need to flush each leg with mineral spirits because the crud sticks to the inner walls and parts inside.

I'll probably take some flak for this but, if it was me, I'd flush and change out the fork oil when installing the Progressive springs because just replacing the springs leaves all the crud ans contaminated (from moisture ingress) oil in the forks and no, I'm not going to offer machined with drain ports fork legs on an exchange basis. It's actually a straight forward machining job when the legs are removed and disassembled.

It's a matterf of finding the lowest point in the leg and securing the leg in a V Block and drilling, tapping and spot facing the leg to accept a washered drain bolt.

Then it becomes a matter of changing fork oil viscosity to change the dampening instead of changing out the springs. All the progressive (or any other manufacturers) springs do is firm up the ride (no matter what kind of hype they blow about).

It's the dampening that controls the ride and handling characteristics, not the spring rate and fork travel is limited by the mechanics of the assembly, not the springs installed. In actuality, changing out the springs is a band aid on the real problem, if, it's a problem at all. Spring and dampening rates are designed into the suspension to suit the average rider. A manufacturer can't make everyone happy. Clicker shocks, cartridge emulators and remote reservolir's can....at a price of course.

In a nutshell, when you compress your forks (like hitting a bump or a pothole in Michigan :eek:, what happens is, as the fork compresses, it's similar to a hydraulic cylinder except the oil has to go somewhere. In a hydraulic cylinder, the oil is displaced into a hose.

In your forks, the oil is displaced through metering orfices machined into the metering rod and allowed to move into the upper cavity of the fork. It's the metering orfices that control the dampening and handling, not the springs, which, only serve to maintain ride height and provide initial resistance to movement.

That's why, installing heavier springs makes the bike ride worse. It may improve cornering but it does because of the increased resistance to movement, the dampening is unchanged in either rebound or compression. Afain, the dampening in either direction is controlled by the internal metering orfices, not the springs.

The only economical way to change the dampening and the handling is to change viscosity of the fork oil. The metering holes are a specific size and number and they only allow so much oil to pass at a given viscosity. Increasing the viscosity, increases compression and rebound dampening, decreasing it, decreases the dampening, which, is why fork oil comes in a wide range of viscosities.

That's why aftermarket rear shocks 'feel' so much better. OEM rear shocks have little compression dampening. They rely on the coil spring and rebound dampening to control the ride.

I probably made matters worse but I'd be changing fork oil before the springs. Just changing the springs without changinf fork oil is like taking a shower and putting on dirty underwear.:rolleyes:
 
hay hellfire where did you get them and how much i like the ride out of the rear shocks but the front forks are way to soft ??
I got the shocks and springs drop shipped from Progressive through Summit Racing. After looking around for the best price and shipping, they could have them to me in 4 days. Every other place wanted to order them and then ship them to me, so the others couldn't give me an estimated delivery.
Springs were only $75 and took the dump truck ride out of the front end. I don't see any reason to change the fork oil in a two year old bike and I'm happy with the ride change just the way it is. I'm beginning to think flip would disagree with me even if I bought more of his parts.
 
Ok, Flip, that makes some sense to me. I have 412 1/2 inch longer HD rears and they are great. Did the Progressive front thing and thought I liked it better the first day. After the first 1000 miles I did not care for the change and will swap back to stock next fork oil change. The bike did corner a bit better, but only a small bit while the ride went to crap. As a R3 rider who draged the pegs on a regular basis prior to the change I found that with any mid corner bump at all the front would drift after the change. I used the recommended oil from Progressive.

For me-rear shocks-great improvment. Front springs-not so much.
 
I can get Progressive Suspension components but I don't offer them on site because every swing'in *****sells them.......:D

The reason the rears make a big difference is the dampening, which is non-existent (rebound) in the OEM shock. The front forks already have fairly good valving so a spring swap does nothing but increase the resistance to movement. Progressive hypes their progressive wound springs, but the fact of the matter is, the diameter of the steel and the heat treat of the spring is what determines the ride quality.

It's the front fork oil that makes the difference. You could change the valving by brazing the orfices closed and re-drilling them to a smaller diameter which will slow down the oil flow and thus increase the dampening, or you could go the other way and increase the diameter for a softer, less dampened ride.

This winter, I'm tearing my front end down, upgrading my stanchions and installing alemite fittings in the headstock, something that should be in all headstocks, used to be in early years but are sadly lacking in late model bikes.

On consideration, I would machine the lower stanchions for drain plugs but it would be the same as I do on Panniers. The legs would have to be stripped of internals.

....and I'm not a fan of Wilburs. Like Staintune, Wilburs are overpriced. I don'r believe in gouging just because the market bears the thought.
 
Once again, I'm suffering from hallucinations of improvement when I make a modification. Should I just check with you before I do anything, or just afterward so that I don't report on my own findings should they contradict with yours? Afterall, I'm not making any money selling parts.
 
I see your opinion on willburs is that they are overpriced do you feel though that the product is immensely better or just better because pretty much all german R3 are equipped wih these and I wonder if I should spring the money or look for something less expensive ,
your vast experience is appreciated in these matters.
 
...and I'm not a fan of Wilburs.

I see your opinion on willburs is that they are overpriced do you feel though that the product is immensely better or just better because pretty much all german R3 are equipped wih these and I wonder if I should spring the money or look for something less expensive ,
your vast experience is appreciated in these springing matters.
 
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