Hello! -----Original Message----- From: JЭrgen Mages <jmages@xxxxxx> To: python@xxxxxxxxxxxxx, Dak the TFI <daktfi@xxxxxxx> Date: Mon, 07 Aug 2006 10:48:17 +0200 Subject: Front Suspension > Encouraged by this discussion I taxed my brain and got > out a solution witch might work: > > - mount a hinge between the steering pivot and the front part > - the hinge has a stopper in the lower position > - a pretensioned rubber is placed below the hinge > > The principle is similar to the rear suspension. The rubber > is preloaded so that the system weight is compensated. > > When the rider pushes the pedal, nothing happens to the > suspension as the pushing force is towards the stopper > plate. > > When a road bump is passed over, the force is directed > to the opposite direction and the front part can fold > upwards (suspension) and is later pulled back to the > home position by the rubber. I thinked about this variant too, but got two question. First, I need susp for bad roads, and this construction will decrease ground clearance. That's BAD! Of course, it's possible to change frame geometry, rising it, but this solution has it's own drawbacks. Second, this thing will "bang" each time it returns in place. And I speak not about noise, but shock stress on the hinge. How many times goes it to live? So, we need some dampener between hinge and fron fork, which leads us back to interference from pedaling (somewhat decreased). The idea that just came my head is to make double forks. Upper one is hard-welded to pivot and holding BB (like one that now exist). Lower one in hanging on axle near pivot, carry front wheel and it's front part is "suspended" by rubber block between under BB and above lower fork. From side it will look like a crocodile holding rubber block between foreteeth. :-) I make a sketch to make it clearer. However, this construction is VERY HEAVY, since both upper and lower forks has to be very stiff (perhaps even stiffer than original single fork). So, quest for front suspension still continues. :-) --- Dmitry Kuteynikov
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