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Pulse jet Bike

Posted: Mon Jan 13, 2014 1:18 pm
by rhino600
Anyone know if there are any restrictions stopping a pulse jet bike running at the lake. Obviously after passing the tech inspections etc....

Re: Pulse jet Bike

Posted: Mon Jan 13, 2014 1:37 pm
by hawkwind
Not allowed ....unless it drives the wheels directly.... no propulsion vehicles allowed for in the rules ie. jet or rocket ....though you may be able to do time only ? need to contact the bike scrutineer.

What is it that you have ? any pics :)
cheers

Re: Pulse jet Bike

Posted: Mon Jan 13, 2014 1:56 pm
by rhino600
Bummer. Just have an engine and was liking the idea of building a bike.

Cheers

Re: Pulse jet Bike

Posted: Mon Jan 13, 2014 2:58 pm
by gennyshovel
4.D AUTOMOBILE:
For classification purposes, an automobile is a land vehicle propelled by its own means, run on at least
four (4) wheels, not aligned, which shall always be in contact with the ground. Steering shall be assured
by at least two (2) front wheels. The automobile shall be propelled by at least two (2) wheels. One pair of
wheels shall be on the same transverse centerline.
4.

Re: Pulse jet Bike

Posted: Mon Jan 13, 2014 6:29 pm
by rhino600
So I assume its similar rules as to the cars then. I couldn't see anything in section 7 but assumed I was having a man look :)

Thanks for your help

Re: Pulse jet Bike

Posted: Tue Apr 08, 2014 2:14 am
by gidge348
You could of course run your pulsejet with a free power turbine powering the wheels.

https://www.youtube.com/watch?v=uqMn0A2aUdo

Re: Pulse jet Bike

Posted: Thu Apr 10, 2014 1:09 am
by David Leikvold
Nobody has ever been able to convincingly explain why our rules still preclude the use of thrust powered vehicles. Some people have said it's too easy to go fast with a jet, there's no challenge in it, but that's wrong. First of all, you have to build the vehicle, then get the jet (or whatever) to work properly and then you have to drive it, which would be exciting, to say the least. All three of those sound like a challenge to me and none of them easy. Of course you can't walk into the local speed shop and spend thousands and come out with 200+ mph of off the shelf speed parts. You have to work it out yourself, find the engine you want or have to settle for and then put it all together. And it doesn't have to be outrageously expensive either, obsolete jet engines are essentially useless so they aren't that expensive, especially when compared with any engine putting out several hundred horsepower more than it originally did.

A set of rules would be easy, just use the existing special construction rules and maybe the weight classes for electric vehicles. Add a few rules specific to thrust vehicles and the rest is up to the builder. The limiter would be tyres, Mickey Thompson tyres can apparently cope with 400mph, which would easily grab the attention of the driver! Or take it a bit easier and run 300mph Goodyears with a smaller engine. Don't forget that jets have been used for LSR since the 1960s.

Cheers
Dave :mrgreen:

Re: Pulse jet Bike

Posted: Thu Apr 10, 2014 7:18 am
by Greg Watters
You can run FIA/FIM , there is one jet bike entered for the shootout this year , http://www.jetreaction.net/

Re: Pulse jet Bike

Posted: Thu Apr 10, 2014 10:31 am
by DLRA
Let me say upfront I have no problem with thrust powered vehicles.
Let me pose this comparison. You do not see sail boats competing with motor boats. That would be crazy right?
Well wheeled vehicles are the same. A sailing boat is the purest form of the many variants and types of boat. Well the same can be said of wheel powered vehicles. Are they cars or bikes, yes, but they are different and one has an obvious advantage over the other. You also don't see many combined sail and motor boat races. They are similar but different.
Apart from this is the historical fact that jet powered vehicles did not exist when the SCTA was formed and the fundamental requirement for SCTA vehicles to be wheel driven and our rules are based on the SCTA rules.
There is also the infrastructure required to support this form of land speed racing.
What I am talking about here is the technical inspectors with the knowledge to not only be able to enforce the unique rules for these types of vehicles but have practical experience with the wide variety of jet engines that would be available.
Also what special requirements would be needed from our Fire and Rescue crews?
All of this to cater for what would be a very much minority of vehicles at any event.
Look at it from the perspective of how you would support this form of racing and when you take into consideration all the other requirements to run an event and it all gets too hard.

Re: Pulse jet Bike

Posted: Thu Apr 10, 2014 3:28 pm
by David Leikvold
Mr Watters, thanks for getting Richard Brown onto our forum, he's impressed me for many years.

Mr Wapling, you raise interesting points, I'll try to answer them as best I can. I'm also pleased that you have no problem with thrust powered vehicles. That's a good attitude.

Technical inspectors: My brother, Peter, has 40 years experience as an engineer with QANTAS. What he doesn't know about gas turbines could be written on the back of an envelope. If a jet thingy ever turned up he could scrutineer it easily. He sets high standards too, so a junker would be sent home. Incidentally, Pete said he was very disappointed with most of the lock-wiring he saw this year so he will make himself available at scrutineering to do a proper lock-wiring job free for anyone who wants it.

Jets are like Top Fuel engines, they only stop when you turn the fuel off, so if it used an electric fuel pump isolating the battery would stop the engine. With solenoids in the fuel line the unburnt fuel could easily be isolated from a fire. Actually, that's not a bad idea for every competitor. Fire and Rescue guys would treat a jet fuel fire the same as any other gas or fuel fire.

Special considerations: If the jet cars were run first thing in the morning and last run of the afternoon the start line wouldn't be a problem. Failing that, if a jet turned up with a group of cars we'd just hold him back until last of the group and let him go when there was nobody behind him. Spectators aren't allowed to wander around in the staging area anyway and you'd only stand behind a running jet once unless you were Bart Simpson.

Your sailing boat and motor boat analogy doesn't take into account that all our runs are solo, what is lined up before you or after you doesn't make any difference. We have tiny little bikes and we have Trevor Slaughter going at least three times as fast at the same event. They aren't racing against each other so there is no "advantage".

Scott Andrews told us sincerely at the auction that copying everything Bonneville did wasn't a good idea. He encouraged us to do things our own way. He came to our Speedweek because he wanted to learn about our wireless timing system. He is very keen to copy our idea and wants to get rid of their current system asap because they have to use 35 miles of wire to make it run. Thirty five miles :shock: !

The Texas Mile people run jets. Just because SCTA doesn't have thrust vehicles doesn't mean we are under any obligation to copy them. In this instance tradition is pointless. I'm sure there would be people who would whinge about a jet car being "too fast, too easily" but I'm also sure that if they were offered a drive they might suddenly not be so disrespectful of "easy" speed.

Having said all that, I think we'll have electric vehicles running before we get thrust vehicles. I hope the Catavolt guys come back.

Cheers
Dave :mrgreen:

Re: Pulse jet Bike

Posted: Fri Apr 11, 2014 1:39 pm
by David Leikvold
One thing I forgot to mention was how ridiculously simple pulse jets are. Any sheet metal shop can make one for peanuts, they're just a three piece round steel tube with a reed valve at the front, a fuel spray and an ignition source. If you turn off the fuel pump they stop. The Nazis used them back in WWII on their V1 buzz bombs. The reed valve cycles at 50Hz so they sound like a hugely powerful and VERY noisy single cylinder four stroke doing 3,000 rpm. They were good for 400 mph in level flight. You Tube is full of examples of pulse jets. So if you can't afford the expensive internal combustion engine or the out of time jet engine your heart desires...

Cheers
Dave :mrgreen:

Re: Pulse jet Bike

Posted: Sat Apr 12, 2014 9:17 am
by AuotonomousRX
Here we go I am half way there Dave

Image

Pete

Re: Pulse jet Bike

Posted: Sat Apr 12, 2014 10:27 am
by grumm441
David Leikvold wrote:One thing I forgot to mention was how ridiculously simple pulse jets are. Any sheet metal shop can make one for peanuts, they're just a three piece round steel tube with a reed valve at the front, a fuel spray and an ignition source. If you turn off the fuel pump they stop. The Nazis used them back in WWII on their V1 buzz bombs. The reed valve cycles at 50Hz so they sound like a hugely powerful and VERY noisy single cylinder four stroke doing 3,000 rpm. They were good for 400 mph in level flight. You Tube is full of examples of pulse jets. So if you can't afford the expensive internal combustion engine or the out of time jet engine your heart desires...

Cheers
Dave :mrgreen:
My Dad was in England during WWII. he said it was always good when you could hear them
However it was not so good when you heard them stop
G

Re: Pulse jet Bike

Posted: Sun Apr 13, 2014 2:41 pm
by gidge348
I agree that trying to put in the infrastructure for the all out ultimate world speed record where they all seem to be chasing 1000mph would silly for the club to do.

But as long as they ran to a max of say 350-400mph, the current infrastructure should be fine... (and it would be cool to see something screaming along the salt at that speed.)

I don't think the fuel would be a big problem, in a lot of ways it would be a lot safer than other fuels used at the moment, it is basically a refined kerosene. An alternative (comparative) fuel that jets can run on is a mixture of 90% diesel and 10% gasoline. No invisible flames of Methanol, instability of Nitro, Gas cylinders of Nitrous Oxide or even the flash point of Gasoline or Avgas. For the purposes of the fire crew I believe it would be dealt with the same as diesel.

The engines are "mechanically" quite simple and in general VERY reliable (in an aircraft, you can't pull over to the nearest cloud if the engine dies :wink: ) unlike a modified road engine. Just think of a big turbo charger without a piston engine attached only a burner can.

I am sure they can be raced along wheel driven cars; the only question is will the club allow them and what classes we would want.

I for one would love to bring a J34 jet car out to the salt.

Cheers Ian...

Re: Pulse jet Bike

Posted: Sun Apr 13, 2014 2:47 pm
by gidge348
AuotonomousRX wrote:Here we go I am half way there Dave

Image

Pete
Yep, just throw away the pesky carb, pistons, crank, gearbox, chain, radiator etc, etc and you will be there. :)

Ian...