Was wondering if anyone wants to donate some rocket motors to kick this
thing up to about 30 mph.
Even if you don't want to donate, would you have any recommendations for the
size of motors? I'm pretty light weight at about 135 lbs. The trike itself
weights about 60 lbs.
I wouldn't want to go much faster than 30 mph at first because this thing
can flip pretty easily. However, as I get use to handling that speed, I
could possibly graduate to higher speeds on a straight-away.
The rocket motors normally used by the folks on this group cannot be
throttled or shut down once they are started. At nearly 200 lbs.I would
think that it would take a fairly large motor to move the trike and you at
30 mph. I would suggest a Hybrid motor, one that runs on liquid Nitrous
Oxide for the oxidizer and another substance to burn and produce the "hot
expanding gas" for the thrust. A hybrid motor could be modified to allow
the nitrous to be shut off effectively shutting down the motor. In theory
you could re light the motor at a later time though I have no knowledge of
how this could be done.
Do a Google search on hybrid rocket motors to see what is out there.
An alternative would be a Hydrogen Peroxide rocket motor but the fuel is
extremely dangerous at the concentrations you would need.
Check out http://www.the-rocketman.com/ for some ideas.
I see top posting is common in this group, so I trust I won't get slammed
for doing it...
I don't think it would actually take 200 lbs worth of thrust to push a
wheeled vehicle that fast - after all, it isn't lifting it.
However, I am noting your comments on a hybrid motor. I have looked into
pulse jets, but they appear to be too bulky for this use. As for Nitrous
Oxide, that is also kind of bulky, but I suppose I could use a smaller tank
than what I normally see in cars. My neighbors often install nitrous kits
in cars for the local track, so I could get some help there.
Um... doesn't Hydrogen Peroxide use Hydrazoline? Or some kind of heavy duty
I have a couple of thoughts on this. One is, it wouldn't have to start from
a dead standstill. I could pedal it up a bit and kick in the burners.
Another would be to use a number of motors that I could ignite
individually - instead of taking the risk of getting up to undesirable
speeds in early testing.
I have only worked with bp endburners so far (sky rockets) but have not
attempted to put them on the trike. The largest I've ever made would
probably be considered a 3 pound rocket. But I believe I have the equipment
to make them a little larger, reliable, and safe. I don't like core burners
because they tend to blow out my nozzles on ignition (but that just means I
need to improve my tooling and materials).
Anyway, thanks for your input. I'll look into your recommendations.
Been there, Done that... with a regular bicycle when I was 12. I would
suggest using a regular bycycle though as the thing you want to ride is
marginally stable and would tip over easily.
Another thing... if you use rocket motors don't ignite them when you
are still, as they will probably push you over and not foreward. Be
going a few miles an hour when you hit the button.
Also be aware, like the other guy stated, once lit you can't turn them
off if something goes wrong.
On the bicycle, we used 5 SSRS F67 motors and lit them one at a time.
They worked pretty good and they definately accelerated the bicycle,
but I doubt we got to 30 mph, probably 20-22 mph. Looking back, we did
some pretty stupid things! What's the saying... A little knowledge is a
Anyway, hybrids are the way to go but they cost a lot to set up and
opperate correctly, so I'd suggest AP motors with an average thrust of
125-175 newtons and that last for no more that 1-1.5 seconds of burn
time to start off with. These would seem manageable.
And... BUY YOUR OWN DAMN MOTORS! Mad scientist types should be funding
their own experiments and not bumming stuff off of other people!
What's wrong with poeple from Florida! :)
Piccolo Pete wrote:
I would definately start pedalling before lighting them and I agree, with
solid fuel, I would want several motors to light in pairs (to keep some sort
of balance and avoid a rapid steering problem). But you aren't gonna talk
me out of using the trike if I ever do this :-)
Max speed I've had the trike was 25 mph - but that's about as fast as I ever
want to go on a sidewalk. This would eventually be run on a nice smooth
track - just for special occasions - and I would hope to eventually exceed
30 mph (wearing protective gear, of course). Fortunately, even though the
trike can flip easily, it isn't a far distance to the ground and most of
what I would be subject to would be scrapes/road burns unless an explosion
takes place (which is why I'm not really looking forward to using liquid
I was thinking, um, after all, I do have brakes... Even though I may have
to replace them after every run.
I'll look into the AP motors you suggest. I may just start with some hand
made bp motors to get a feel for it. 2 six pound rockets with a 20 foot
flame would look pretty cool on this thing.
As for your comment about Floridians... our brains get melted every
summer - what do you expect ;-)
Besides, pride is cheap and it doesn't cost anything to ask :-) You never
know when someone might be willing to sponsor an event. I know a guy that
travels all over a few countries and makes $10k per show for riding a horse
cart full of pyrotechnics around a track a few times. It costs a lot for
the airfare, permits, and supplies, but he still makes a nice profit. So...
why shouldn't I try to get into some kind of profit thing with a trike that
already draws a lot of attention every day I ride it to the store to get
some beer? Hell... I should probably sell advertizing space on the thing
Aerotech... are you out there?
I caught this on tv a couple years ago. groups of hobby motors seem
like a good way to do it.
also, a set of motorcycle leathers would be a sound investment.
shameless plug... I've got a set of leathers on ebay now that i'm
selling for a friend. (sounds like they might fit you) auction ends in
2 days and current bid is only $33. just do a search for spartan
leathers, you'll find them.
Those are some old school leathers. Not too many people would trust
them, as years of sweat turns the leather into beef jerky and they
become less effective. Even without a lot of use the leather experts
recommend replacement about every 10 years.
For 30 bucks they would be ok for a 30mph bicycle ride, but no way would
I go race in them.
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