Duxuk
Retro Guru
I recently acquired a Proflex Attack LE and am pleased with many aspects of it. The rear end has a new elastomer from SuspesionForkParts in the USA. It keeps the rear wheel feeling planted and is definitely better than a hardtail for grip on stoney surfaces. The front end, meanwhile, is poor. The Rockshox Quadra 5 may be a little tired. It sags a good way when I apply my weight and the rest of the travel is notchy. My first fork, in 1995, was a Quadra 10 so I'd been expecting mediocrity, at best.
If you ever read the homepage of my MTB blog https://wordpress.com/media/mountainbiker.home.blog you'd know that the Q 10 wasn't really my first fork. That accolade goes to a homemade leading link fork I made for my "scrambler" in 1977. I was 15 years old and had found that the best sport I'd ever done was ride a beaten up old pushbike off road, basically mountain biking but with a different name. I know now that many of us had this same experience and I don't doubt that others made suspension forks but no one I knew had done so. When I heard Charlie Kelly speak about the origins of MTB I had the chance to ask him if they'd ever thought about suspension in those days. After early but unsuccessful attempts it took until around 1990 for things to really get going. If I'd been in Marin county in the seventies I could have changed the whole course of MTB history but instead my fork fractured after a few month so I was back to rigid forks.
Now I have the skills and equipment to make a much better fork I thought that it would be an exciting project. What I'm doing has been in the planning for a month or so and will be easily reversible so I can't be accused of ruining a historical artifact of such importance as the Proflex.
I love linkage forks so I already own 2 early Whytes and had one when they were current. I like the Girvin Vector but thought I could improve the anti bob characteristics to mimic the Whyte linkage hence the "No Bob Girvin". I've made some changes to the linkages and will achieve 3 inches or a little more of travel. I'll also be able to improve the rather head down riding position with a longer steerer tube also housing the top linkage mount. The longer travel fork will also slacken the head angle to make it less twitchy.
Progress so far.
The top linkage mounts for the fork tops with nylon bushes, soon to be lined with steel for 10mm bolts.
A bit more filing needed.
Squarish. It'll do.
Once the weld's dressed it looks good.
Exactly 106mm between the legs and perfectly parallel. The dropouts will affix inside the legs and adjustment will ensure the wheel is upright and perpendicular, so no need for a jig.
I've built 5 self designed and self built sports cars so can assure any doubters that this is greatly over engineered for a bike. The legs are very much like the front suspension wishbones of a car.
If you ever read the homepage of my MTB blog https://wordpress.com/media/mountainbiker.home.blog you'd know that the Q 10 wasn't really my first fork. That accolade goes to a homemade leading link fork I made for my "scrambler" in 1977. I was 15 years old and had found that the best sport I'd ever done was ride a beaten up old pushbike off road, basically mountain biking but with a different name. I know now that many of us had this same experience and I don't doubt that others made suspension forks but no one I knew had done so. When I heard Charlie Kelly speak about the origins of MTB I had the chance to ask him if they'd ever thought about suspension in those days. After early but unsuccessful attempts it took until around 1990 for things to really get going. If I'd been in Marin county in the seventies I could have changed the whole course of MTB history but instead my fork fractured after a few month so I was back to rigid forks.
Now I have the skills and equipment to make a much better fork I thought that it would be an exciting project. What I'm doing has been in the planning for a month or so and will be easily reversible so I can't be accused of ruining a historical artifact of such importance as the Proflex.
I love linkage forks so I already own 2 early Whytes and had one when they were current. I like the Girvin Vector but thought I could improve the anti bob characteristics to mimic the Whyte linkage hence the "No Bob Girvin". I've made some changes to the linkages and will achieve 3 inches or a little more of travel. I'll also be able to improve the rather head down riding position with a longer steerer tube also housing the top linkage mount. The longer travel fork will also slacken the head angle to make it less twitchy.
Progress so far.
The top linkage mounts for the fork tops with nylon bushes, soon to be lined with steel for 10mm bolts.
A bit more filing needed.
Squarish. It'll do.
Once the weld's dressed it looks good.
Exactly 106mm between the legs and perfectly parallel. The dropouts will affix inside the legs and adjustment will ensure the wheel is upright and perpendicular, so no need for a jig.
I've built 5 self designed and self built sports cars so can assure any doubters that this is greatly over engineered for a bike. The legs are very much like the front suspension wishbones of a car.
