i was thinking the same thingfreerider67 said:
is it me or is this design really wierd........
JBsoxB
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i dont know how it would work, itseems like your weight coming down and the suspensioin coming up would cancel each other out. i dont know if im just an idiot but it just doesnt seem right to me, let me know what you think and if anyone has any experience tell me about it.
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It's just a linkaged variation on the old Integrated Rear Triangle (IRT) idea by John Castellano that was bastardized by everyone else in the mid '90s. The part of the original idea that is relevant to this particular Storm H2 frame is that by locating the bottom bracket on a suspension member the compression movement of which is opposed (from somewhat to a lot, depending on the design) by putting weight on the bottom bracket. The point of this design comes from cross-country, where climbing-out-of-the-saddle is normal and used to send the early dual-suspension bikes bobbing like crazy. On an IRT bike, getting off the saddle transfers most of the weight of the rider onto the bottom bracket, which is on the suspended member, effectively opposing its movement and reducing the rear end's propensity to compress under each stroke.
(The other part to the original IRT idea is that in the early days of full-suspension, the upper chain length would vary quite a bit upon suspension compression. The main effect was actually the other way around, in which putting tension on the chain, aka pedaling, would acutally generate a force to either compress or extend the suspension. This made the bike either bob or "inchworm" as you pedaled hard. IRT eliminated that problem by putting the ENTIRE drivetrain on the swingarm, eliminating any lengthening/shortening of the upper chain.)
This idea is somewhat applicable on flatter, smooth DH courses where the ability to sprint is important, but do remember that this design came about before the heyday of remote lockout and "platform" valving. This idea is pointless for shuttled freeride and technical DH, because as you both were beginnign to suspect, there is no reason why anyone would want to fight suspension compliance with your body weight, especially considering that if you lose, YOU'RE the mass that's being accelerated away from the bike.
The IRT concept also died in XC circles mostly because compliance was lacking (even when seated), and for certain popular bad copies, traction would acutally decrease as resistance to pedaling increased (steep climbing, deep sand).
(The other part to the original IRT idea is that in the early days of full-suspension, the upper chain length would vary quite a bit upon suspension compression. The main effect was actually the other way around, in which putting tension on the chain, aka pedaling, would acutally generate a force to either compress or extend the suspension. This made the bike either bob or "inchworm" as you pedaled hard. IRT eliminated that problem by putting the ENTIRE drivetrain on the swingarm, eliminating any lengthening/shortening of the upper chain.)
This idea is somewhat applicable on flatter, smooth DH courses where the ability to sprint is important, but do remember that this design came about before the heyday of remote lockout and "platform" valving. This idea is pointless for shuttled freeride and technical DH, because as you both were beginnign to suspect, there is no reason why anyone would want to fight suspension compliance with your body weight, especially considering that if you lose, YOU'RE the mass that's being accelerated away from the bike.
The IRT concept also died in XC circles mostly because compliance was lacking (even when seated), and for certain popular bad copies, traction would acutally decrease as resistance to pedaling increased (steep climbing, deep sand).
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I think you mean URT, Unified Rear Triangle as in Catamount, Schwinn Sweet Spot, Klein Mantra, etc.
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urts suck balls. me no like
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that is actually a really good design because it uses a bellcrank like a motorcycle but has those other peices to increase lateral rigidity, i think. if done right, a bell crank allows you to both sprint on flat and take big hit without bottoming. the japaneese have figured this out pretty well and without it you wouln't be able to take an mx bike down a flat section of track and have stiff suspention, and he a 30 foot doulble right after and soak up the landing. i think theese peolpe have really thought about " when going through travel, the wheels don't move, but instead the mainframe colapses into them" meaning that the wheel base never changes, but the frame basicly "gets smaller". the proble with the design is the bb, if it had been on the mainframe it would be way better, it would also be better if the bottom pivot went around the bb shell like on a cowan ds...
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nice FSR pattern though....
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Yes, I meant URT. Thanks for the correction.gratefulbiker said:
It's a linkaged variation on the URT concept, but no, it is not technically a URT since like you said, there is no triangulated swingarm on which the entire drivetrain is located. But the facts that 1) the BB is located on a suspension member, 2) you can partially counter suspension compression by applying weight on the BB, and 3) the BB-to-seat distance changes upon suspension compression does mean that it is a related concept. The fact that most prior URTs were single-pivot designs is secondary. There was a URT (can't recall the name) that was pivoted off of two short links (a la VPP, DW-link, Maestro). The axle paths are different between the SS URT, 4-bar URT, and this Storm H2, but the effect of putting the BB on a nonsuspended (or semi-nonsuspended) member is comparable.zedro said:
Wher do you see a bellcrank? It's pretty obvious on a RMX, but I see only a Lawill/FSR-type 4-bar driven straight off one of the bars.scabrider said:
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The new Haro cross country design uses this layout. Pretty weird if you ask me...DtEW said:
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The I-Drive design and the Mongoose variant are both single-pivots though...gunfodder said:
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no... i dont need a new bike.KennyO said:
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Nope, I don't like it.
My Supercycle (don't wory it's not my only bike.) has about 1 inch of travel and the BB coming up is bad enough.
I can't imagen 6-8 inches.
My Supercycle (don't wory it's not my only bike.) has about 1 inch of travel and the BB coming up is bad enough.
I can't imagen 6-8 inches.
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That's exactly what you need to do... I've owned a URT and to get the thing to work through the complete range of travel you need to be seated, thus putting all your weight on the front triangle. It still has some travel when you're standing, but you do lose a great percentage. You totally feel the bike getting plush as soon as you sit down...but you can't stay like that for long or you'll get bucked! How many DH riders do you know that do the whole course seated? Uh... none and thats why you don't see that design anymore or the sweet spot designs... it's too bad because they totally eliminate chain growth problems, and bio-pacing [pedal induced bob]jp3d said:Ya as the suspension compresses the BB moves UP??? it looks like you have to have all your weight on the seat to actaully have any suspension under you...
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