The Sky's (almost) The Limit @ The Salt Flats!

Discussion in 'Races, Events & Group Rides' started by augidog, Oct 23, 2008.

  1. augidog

    augidog Banned

    y'all have heard enuff about the great time i had at bonneville, let's talk about how the MB was received. dennis has run there a few times, so an MB wasn't anything new...but my approach was new. i registered, paid, and ran in the 130MPH Club, S-2 was considered a "vehicle"...and that's how we came across.

    i've been in communication with dan wright, lead tech inspector for USFRA. he agrees that the motorized bicycle could be the next "new thing" on the salt, and he's being very encouraging & tons of help.

    in a nutshell: motoredbikes would run in the 130MPH Club, so the rider will have to fully suit up for safety. trust me, ya don't wanna find out why the hard way, it's one nasty surface.

    hehe...that's the bad news, but here's the good. the reason there's so much emphasis on personal safety is because there's but the minumum of regulation on chassis design and integrity. i'm sure there was some kidding to it, but he said that if your huffy cranbrook "fell to pieces at 50mph, you call it parts & wait 'til next year"...because of the inherent limitations of certain bicycle components, there may be a 50cc limit, that will be for the usfra meeting to decide on. in our case a single paragraph will likely suffice to define our "specialty class" within the Club. if bigger engines are allowed by USFRA, i think MBRA itself will still stick with 50cc to keep the field interesting, as the new limit up from 48 includes at least one example of all the popular engine styles.

    land-speed is about you and the clock, so the other cool part about this is that MBRA can host an "open" class solely for land-speed competition. this is only conjecture at this point, but dan suggested that MBRA might could have a "specialty class" arrangement similar to the 36HP Club:

    within MBRA itself, we could break things down into a set of sub-classes, based on engine-size of course. whizzer's are welcome to join into a sub-class of MBRA if anyone wants to. to compete within MBRA, be prepared to confirm your engine-size, you know why i have to say that. if we preferred to (i DO suggest) we could agree on some rudimentary chassis standards, just because we know better & we'd be setting a good example, but in the long run it'd be about your own choices and how good yer leathers are.

    nobody needs to join MBRA to run bonneville, but it make it a lot more fun.

    i would think that anyone who set about the project like i did, staying accountable & being productive, could find the support...once you do make it there, you camp for free and all you need is fuel, water, and maybe that order.

    it's the greatest experience you could ever hope to have...let's RIDE!!
    Last edited: Oct 23, 2008

  2. Wishbone

    Wishbone New Member

    50cc Limit

    Great idea. A 50cc class would be a nice limit. What kind of speeds do you think are possible. I have visions of "The Fastest Indian" w/ Anthony Hopkin's dancing across the salt flats.
    New speed record for fastest human pedaling set this year in Nevada, Battle Mountain by Sam Whittingham on Varna ~ 82 mph. Do you think someone pedaling a MB could do better?
  3. augidog

    augidog Banned

    the 130MPH Club runs a 1-mile course...

    no-limit on pedaling or pedal-gearing, 50cc single-speed engine-assist...i fast do you think you can go?

    one more thing...believe this: at MBRA we leave the engine-politics at the door & we do our talking on the track...

    so, let's ride :cool:
    Last edited: Oct 24, 2008
  4. Wishbone

    Wishbone New Member

    50cc is plenty of power. The proper gearing will help, but aerodynamics will have the biggest effect on top speed. Air Resistance = Frontal area x Coeffient of drag (Cd) x air density x Velocity Squared. For a typical MB ; Cd ~ 1.0, FA ~ 5 ft Sq, assume density of air ~ 0.075 lbm/ft sq. Given an MB w/ 1 HP motor, will result in top speed ~ 30 mph. Try to double that & your air drag will increase ~ 4X. Some of the best streamlined vehicles: recumbents & solar racers have Cd's < 0.01. That low a Cd is very hard to achieve , but a Cd of .1 is realistic. How low you can go will determine how fast you can fly. I think 100 mph would be a nice target. Any one want to try?
  5. wavygravy

    wavygravy Guest

    good stuff

    now were getting somewhere! good stuff wishbone!
  6. I think your allowed a push to get you going if your geared too high to start yourself!
  7. bamabikeguy

    bamabikeguy Active Member

    Stock 2.25 tires front and rear?

    I'd guess there is a 70 mph speed barrier.

    Modified, electric hub on front to gain momentum?

    90, tops.
  8. augidog

    augidog Banned

    from USFRA's perspective, there's discussion of a 60mph "breakout" with a Motorized are correct, bama', it's about tires.
  9. bamabikeguy

    bamabikeguy Active Member

    It would just seem, past that "sonic boom" limit, it would become balancing on a tight wire, or speed skating using just one skate.

    I know, at maybe 45 mph down a steep grade, things get shaky.

    edit: On Rocinante, I have a 4 foot long bungie cord, which I hook under my big basket, loop around the seat post, taut enough to stop it from turning too much one way or the other while parked.

    That might be a stablizer for high speeds, the basket would not aerodynamically hinder you, then pull one of those black rubber bungies around, which would be the equivalent of the diff between power steering and the old manual steering on a car, just enough play in the front to make 10 degrees worth of turning left or right.
    Last edited: Mar 20, 2009
  10. augidog

    augidog Banned

    "sonic boom"

    hehe...i returned to the pits after that best run, went up to a small gathering of 130MPH motorcycles, sed "everyone who's gone 1mph/cc raise your hand":jester:

    the surface, when pristine, is plenty firm...but if someone spins a tire, or an area gets too much steady traffic, it begins to behave like dry snow. i dunno how the various bicycle guys dare use skinny tires on that stuff, some natural cracks & grooves in the salt are wide enuff & will grab ya.

    if motorized bicycles ever achieve true vehicle status, the racing clubs are gonna require a steering-dampener...easily fabbed when the time comes.