Suspension Fork

[xPosTech]

DasKapitan's post on the 1900's Pierce has become an inspiration for a fork I want to build. His second pic

gives a great view of the geometry of that fork. Measuring (on my screen) from the center of the fork blade dropouts to the top of the fork crowns the front fork is 95% the length of the rear. The front fork will carry the fender and brakes.

I have two matching forks (except for length) from a pair of 70's road bikes. The shorter (26" or 590mm) is 94% of the longer (27" or 630mm). I also measured the bottom rocker and the top link as equal lengths, although they appear to be at different angles (camera angle?).

I think the shock at the top of the forks looks kinda plain but I want your opinion. If you were gonna build this setup, would you do it as a shock at the top or as a double springer (ala Monarch)?

If I build it as a shock at the top, the steerer of the front would serve as the piston rod. I can come up with some tubing for the cylinder. A spring and Delrin piston inside the tubing like a cheap MTB suspension fork or hide a small shock inside? Or a coilover shock from the rear of a full suspension MTB? The two cheap MTB coilover shocks I have use 650 lb/in springs. The coilovers have the added benefit of being adjustable, too.

I'm leaning toward the Monarch type springer. The forks have a really nice curve like the pic above. Nice lugged crowns. The curve in the matching forks would go right in line with the 90's comfort cruiser I'm building. Think a Huffy Cranbroke's small tube uncle.

So what do y'all think? Hidden shock at the top, coilover shock at the top or double springer?

Ted

 

[eDJ]

I was reading in your post in Das Kapitan's thread where you state that you like the "old vintage look" and that Pierce it's old enough to be vintage. I'm guessing a spring is inside the tube on the fore-fork, but still I wish I knew if it was partly pneumatic like the damper on an aluminum screen door ?

It could have been a clever way of providing a mounting for the "Headstock" emblem. In the day Pierce made upscale equipment and would have certainly wanted to tout it's "Tradename" for marketing prestige. (and there is a Headstock emblem on it)
(especially on something as advanced as a 4 cylinder bike like it)

It may be worth an email to the museum's curriator to see what could be learned about it.

Many other less expensive bikes of the time didn't go too elaborate with emblems....keeping it to decals on the tank, air cleaner, or perhaps a fender. (from what I can find in my research)

My own preference is the appearance of the double tapered spring that's wide in the middle. They seem to have the look of vintage machinery, that is if it is to be exposed where it's seen. If I were just building a bike to ride and the appearance didn't matter I'd use one of the MTB rear dampers without the tube covering it.(if it's an adjustable damper)

I'm glad you brought that up.