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A couple of fork questions.

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Ok I was trying to do some research on forks, but I really don't know what to search for so I'll post this thread. The 2005 DRZ 400S forks VS. the 2005DRZ 400SM. I know the basics, that the SM forks are RMZ 250 inverted and the S forks are the same as the E. What Diameter are the RM forks VS. the DRZ forks? What is the major differance in the suspension ride? Do you have to use the RM tripple setup, this one would probably be answered with the Dia. question. If you need new a triple tree, do you need new spacers for the front wheel and a new caliper bracket? I'm just curious about this, so pour on the info.

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Can't answer too many of your questions, but I do know that the S and E use a 49mm Showa conventional cartridge style. The SM uses the RM USD which reduces unsprung weight, supposedly making them more responsive.

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Unsprung weight? Please explain. I'd like to have a bit better suspension, but I'll need some info to make a decision in the future.

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Unsprung weight refers to parts of a vehicle that are not supported by the suspension, such as wheels, axels, lower fork legs, swingarm, etc. In the case of the USD forks, the lower fork legs are smaller and weigh less than the conventional style. Anytime you reduce unsprung weight you are increasing the suspensions ability to react to inputs (bumps). :thumbsup: See link below for a nice explanation of the concept.

http://en.wikipedia.org/wiki/Unsprung%5Fweight

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Oh, I see. That's why the forks are inverted. Less weight on the lower end!?? Kind of like a lighter flywheel, less weight to push around.

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I think you've got it on the suspension. Flywheel wieght is similar. Heavier means more rotating mass and more inertia, which gives you more torque, but slower response to throttle. Lighter gives you snappy throttle response, but less torque. This is one of the big differneces between motocrossers and trail bikes.

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