Landracing Forum
Bonneville Salt Flats Discussion => SCTA Rule Questions => Topic started by: vespazari on December 05, 2007, 02:38:09 AM
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My name is Nate and I am writing from Australia , I am attempting to build a LSRacer so that I can participate in the DLRA races held in Lake Gairdner South Australia. Since the DLRA runs on the basic rulesbook that is presented by SCTA. I figured why not ask for clarification here as well.
My current design is for a 125cc monocoque frame streamliner, under the current rule interpretation is it safe to assume that only a reclined feet forward racing position is permissible? Or is a head first design allowed in a streamliner?
the closest vehicle that I have seen with a head first rider position was in a partial streamliner, is the fact that rider must use safety restraints,harnesses the reason for the change in position, or is there another reason I am overlooking? any input would be appreciated.
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The Costello Rock 'liner (5050B) is a head first 'liner. If you poke around the SCTA site I think you'll find some photos.
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I believe Jim Deist made the safty harness for Jack's 5050. Seems to have a remote, cable release.
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If you were standing where they are, you would see Nick's back. His head is underneath near the front "windshield" just behind the front wheel.
(http://www.universmoto.ro/ams-photos/photogallery/10118_B5050_mic.jpg)
Your design limitations are only based on safety. It's pretty much wide open.
The 5050 streamliner has the record at 151.481 mph. Something to shoot for!
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Well, maybe you'd see Nick's back. The last time we saw the #5050 run, at World Finals '07, it was piloted by a young lady (sorry, I don't remember her name). She told me the story about it -- but I do think she's now the regular rider and Nick has gone on to other projects.
But yeah, the rider is belly-down and head first. For good details see the DVD "Bonneville Wide Open", which features Jack Costella and Andy Sills (I think that's who was his first rider in the bike) and quite a bit of information about the little bike. "B W O" is available from Benn Karne, a frequent contributor on this forum. If he doesn't pick up on the thread you can find him in the "members" folder.
PS The shameless plug about the DVD is prompted only by my selfish ego -- since Nancy appears in the video, too, and there's even a few seconds of me.
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I have pictures here:
http://purplesagetradingpost.com/sumner/bville%20bikes-3/5050-2006.html
and here:
http://purplesagetradingpost.com/sumner/bville%20bikes-3/5050-2007.html
c ya,
Sum
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you may be able to lower FA with a cranium forward riding posisition but the sensation of speed is much higher.....inner ear balance with a total flat riding posisition is also affected....one other overlooked point is being able to see out of your helmet.....put your helmet on and lay on the floor, can ya see out of the eye opening?
you might want to consult your local motorcycle rules commitee about the monocoque chassis.... I thought your rules closely followed the SCTA rules... if so your proposed chassis design would not be legal...
kent
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....one other overlooked point is being able to see out of your helmet.....put your helmet on and lay on the floor, can ya see out of the eye opening?
kent
Maybe that's why they changed riders, to one that's "propped up" a bit in the front....
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Stainless, with all due respect to all parties involved, she wasn't Nancy, that's for sure.
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I was looking at it in line a while back at E Mirage. The harness latch is on the riders back with a release cable running up front to the riders hand.
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you may be able to lower FA with a cranium forward riding posisition but the sensation of speed is much higher.....inner ear balance with a total flat riding posisition is also affected....one other overlooked point is being able to see out of your helmet.....put your helmet on and lay on the floor, can ya see out of the eye opening?
you might want to consult your local motorcycle rules commitee about the monocoque chassis.... I thought your rules closely followed the SCTA rules... if so your proposed chassis design would not be legal...
kent
....while watching the sun go down at Lake Gairdner a few of us were talking and the topic of that riding position came up...One of the guys asked had we considered it for what we were building ...no! It was more the car guys who had a look of alarm about the suggestion and the agreed feeling was " if I'm going to be going that fast something inside me wants my feet in front of my face" however I think there is more to it .Kent's point about balance is one I hadn't thought about , I knew the sensation of speed would be different ...there are other points to consider , you can't breathe as well when you're lying on your chest and your body is close to the limit of it's range of movement too, that is your back doesn't bend much further and so shock won't be as well absorbed.....Finally for someone with a damaged neck the the prospect of watching telly in that position is bad ..let alone racing ..
OK that said when I was a kid I built a billy-cart that was a long plank ....that I lay head first on and rode down the only decent sized hill in our area , great low centre of gravity ....didn't feel that in control though and the bail-out prospects weren't that good.....It didn't have a long career , not sure but I think my dad may have spirited it away...
Lucky Kaiser's recent 'liner was a piece of steel pipe and despite his protestations about it's strength it "didn't have a roll cage" and they wouldn't let it run under the DLRA rules ,
(http://i227.photobucket.com/albums/dd35/Jarman-Stewart/Luckyliner167.jpg)
(http://i227.photobucket.com/albums/dd35/Jarman-Stewart/luckylinerbars079.jpg)
It is possible ,Vespazari ,to make the mistake of trying to "think outside the box" without first having a proper rummage through the "box" itself.........If you spend time going over every 'liner you can find you will see myriad approaches to a relatively simple pursuit . With a lot of looking time you will get a better idea of what you are capable of creating because you will see that the options are fairly narrow , the nut is the very fine detail......
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THIS NEEDS A CHAPTER IN A BOOK
The last words will not be "The End", but "Don't make the same mistake the first time."
Their are a number of very good reasons to not build it the way you propose.
Kent touched on some of the operator reasons and there are many more.
Take rider position for example.
If your head is at the limit of it's travel in an unnatural position, what is going to happen when you crash ?
If the mass of your body is allowed to surge forward, even if restrained every way there is, you will break your neck.
The limited visibility of the liner that was mentioned has already resulted in a near miss at El Mirage that has caused considerable concern.
The required construction methods are minimums and stress skin or supplemented by other methods is allowed and encouraged.
Kent has the remains of a bike designed liner that crashed well over 300 mph and it is a good lesson on survivability.
The largest part was the rider compartment and he went on to make LSR history at speeds more than 100 mph faster. :wink:
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(http://pages.sbcglobal.net/dean4/_images/DSCN1567b.JPG)
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Nate, passenger?? If you're the fella I'm thinking of come over and have a look at the bike I'm building and we can talk all things salt.I'm sure can help in the wright direction.If you can't find my number, email is bonesracing25@yahoo,com.au. Maybe you could streeech a vespa (bring beer :lol)
cheers
Bones
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...........................My current design is for a 125cc monocoque frame streamliner, under the current rule interpretation is it safe to assume that only a reclined feet forward racing position is permissible? Or is a head first design allowed in a streamliner?
I can only see an advantage of head first if you are running a very small engine, which you are. Once you get to say 750 cc and up the frontal area of the motor is going to give you enough frontal area to be in a more conventional lay-down foot first position that has been tested in many crashes. You can also see that Jack has used the conventional feet first approach for the Salt Snake probably due to the fact that it has to have enough frontal area for the larger motors they plan on running.
What if you do the head first and the racing organization takes a look at it and somewhere down the road decides that maybe this is not best in the interest of safety and bans it? Then you are more or less screwed and will have to start a whole new build.
(http://purplesagetradingpost.com/sumner/b-ville%20meets/2006%20BUB-29.jpg)
http://purplesagetradingpost.com/sumner/b-ville%20meets/2006%20BUB-5.html
Eric and John have done an exceptional job with the lay-down feet first streamliner and have run speeds that are in my opinion more impressive than the 5050 liner (not to take anything away from them). I think the 5050 has started to run a 50 cc motor, so maybe we will have some head to head competition between the two of them. My money is on John and Eric.
c ya,
Sum
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There is a THIRD configuration and that's the way rider on/in the Kreidler mid '60s/'70s machines rode.
Kind of a crouch on one's knees.
From unsucsesful LSR bike work,I firmly believe the supine (reclining) seat is the hardest to learn, but you can't argue with the sucess of the fast guys that have gone that way and continue to do so.
We'd messed around with a rider on his belly but with the ability to extend legs out thru stirups in the body sides to balance back in the early '70s. The sides would retract with the rider's legs when balance was achieved.
Not too legal today I suspect!
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My money is on John and Eric.
I'm right with you. It's hard to convince anybody that a record under 200 is amazing, but that's the only description for a record set with a piston you can hide in your hand.
This isn't from their engine, but you get the idea. 133 freakin miles per hour.
(http://img205.imageshack.us/img205/9806/cylindreculassepistondmontage5gb8.jpg)
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Yes I do have the Vesco lightning bolt bike liner in my shop…those whom have seen it at last weeks party all have commented how badly Don destroyed it and walked away. Mike Akatif looked at it today and got a pretty good chuckle when I said they wanted to rebuild it….the problem with a “kneeler” or a belli flopper is when you get your back flat, you cant see out the front of your helmet… Mike McCarty even had problems with the “ironing board” record setter.
Here are pix of the Kreidler…..
The only thing you definitely need to do is to get the riders inner ear above his belli button, you cant lay flat…… when you raise the riders head you will be able to balance the vehicle
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Thank you everyone for your input, I will certainly take all your feedback on board.
My original intention for running is not set a motorcycle land speed record but to beat the records set by the vespa and Lambretta motorscooter manufacturers in the 1950's , under their definition of a motorscooter as a two wheeled vehicle with rim diameter of 10", total capacity of 125c.c and a direct drive transmision ,built directly off the engine cases. But do to the fact that those records were set independently and under no restrictions of safety regulations to build a similar vehicle today, I would not be allowed to run.
Therefore I have decided to continue and attempt to build something using the current regulations.
I am attempting to base a design around my body build which I believe will aid in such a small capacity machine. I am only 5 feet 4 inches tall, and weigh approximately 55kilos.
I sat down last night placed a helmet on my head and with the aid of my trusty camera proceded to take a few snaps of different positions, before I read these replies and figured out that if length is not really a factor laying on your back feet forward would be the lowest possible position you could attain, even lower than head first due to the vision restricions of a helmet. is length really not as big of a concern?
i still did not come to any conclusions on which will be best for what i want to do .
If I decided to go with the kneeled Kreidler position , would this be acceptable today, or have we already confirmed that as long as you are indeed strapped in it will pass current regulation.?
yep bones its Nate I guess after swinging off of roadracing LCR sidecars I just don't want to be a strapped in and can't shake the box monocoque designs
(http://www.vespaclubempoli.it/Foto/Story/Mazzoncini.jpg)
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The kneeling riding position is not a problem...(our LSR sidecar is a kneeler just like Bone's LCR
roadracer)
The problem is in finding a way to attach and mount the safety belts for a inclosed liner...........
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quote
The kneeling riding position is not a problem...(our LSR sidecar is a kneeler just like Bone's LCR
roadracer)
bob do you have to wear seatbelts in your sidecar at bonneville willie
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Sure looks like the thumb got between the hammer and what ever you were trying to hit. :-D
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Willie....no seat-belts on our sidecar required....
in fact we don't won't them.....................................
That video you have watched several times, of our mishap just off the starting line showed that Larry had no problem getting off and away from the outfit.......................................................................
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the scta says if the riders exit is restricted you have to run in the streamline class --then in the streamliner class you would need to meet all of the streamliner rules do they do the same at bub or can your exit be restricted and if so how much and who would make that ruling --is that more than one question ? willie
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BUB also want the rider/passenger to be able to exit the outfit unrestricted..................................
The final decision to be made by AMA Steward
Ken Saillant and FIM Steward Charles Hennekam.
However, it should be noted that the Tech. inspectors and officials are more "liberal" and they do not expect you to bring a saw to Tech.
to modify your bike and/or sidecar. They are.... and have been very open to discussion.
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so nate... ya still plan on running 10"hoops?
kent
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so nate... ya still plan on running 10"hoops?
kent
legal down under kent for motor scooters
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may be legal but ya think they are safe? How fast ya plannin ya go.?...
kent
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may be legal but ya think they are safe? How fast ya plannin ya go.?...
kent
The vehicle will be limited to the speed rating of the tyres ,a direct drive 125cc vespa ,use your imagination :-D
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DefiNATEly going to run ten inch wheels , I would be over the moon to break the lambretta record of 204km which is 126miles , however I do not know If I can afford to go that fast .... I had a visit from bones the other day, and had a chat with him about designs etc... I think that for what I would like to do /achieve a tiny partial streamlined special construction scooter is much more the way to go. the vespa record of 106miles per hour would my stage 1 goal .
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I think that for what I would like to do /achieve a tiny partial streamlined special construction scooter is much more the way to go. the vespa record of 106miles per hour would my stage 1 goal .
In what sanctioning organization are these records? I don't see a DLRA scooter class in their rulebook. FIM scooter records are for very limited modification stock-type chassis.
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Hi all
this is my first post but i,m also looking at building a scooter powered stream liner. been reading some of the previous posts Regarding 10"tyres with these old scooter engines (Vespa & Lambretta) you have no choice on the size of rims as the engine casings on both brands restricts tyre size. But you can buy scooter racing tyres here is a link to the best ones.
http://scooter-center.com/catalog/product_info.php?products_id=8706&language=en&PHPSESSID=55e5345d5e09d012e9d85ab326a97d83
would appreciate an feedback on this subject , and any other comments.Sorry not trying to hijack this post only add to it.
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Though they're not 10" (RIM) size, yrs truly is pretty sure Costella has used tires other than the obsolete Goodyear Top Fuel tires but rather racing tires from the mini-moto road racing world which are7" rim bonifide racing tires from Italy on the yellow laydown bike. The TF tires were for 5" rims.
Not the same, but if those 7"s were run, a precedent has been set, seems to me.
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Make that pocket bike rim size 6.5" and one race tire Mfr is Blata!
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Thanks for your insight,Regarding the link above does anybody think these tyres would be ok as they are for racing use only? my freind has a set but they have no speed rating on them and the link above is the only info iv'e been able to find regarding any, and i have contact the manufacers directly but not reply (and dont speak German). Vespazari i think this will have to be your biggest consideration before doing any thing(please pm me if you have any good answers regarding this)
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nope i dont think so... and neithor does the scta.
kent
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can you give me anymore info into why you and the SCTA think not? I dont think you would do more than 130 mph (209kph)with a vintage scooter engine and the link above say though's tyres have been tested to OVER 200kph with 200kg(440lbs) of weight (I'm from New Zealand and would like to race in the US and Australia as we have no where to race at home here)
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the tires do not have a speed rating and the construction is wrong for sustained high speed use...you can contact the scta for their determination and opinion but they have not allowed them in the past
kent
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Thanks for yor reply, I think i will try to keep contacting the people in germany how produce the tyres and see if we can obtain more info(i.e paper work) and a speed rating(As we all know germans have an eye for detail) as if we can not find a tyre we can not run. In saying that I Know a guy in the UK how does speed trials with a lambretta that uses the stock split rims and tubs, Coninential Twist tyres(70mph rated) and has run 122mph on an FIA track.
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Thanks for yor reply, I think i will try to keep contacting the people in germany how produce the tyres and see if we can obtain more info(i.e paper work) and a speed rating(As we all know germans have an eye for detail) as if we can not find a tyre we can not run.
Send a PM to Porkpie, I suspect he speaks german as a primary language... he might be able to serve as an interpreter, if you can understand his english..... :roll: Just kidding Porkpie :-D
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Stainless - you over wrote my response!
I had typed:
Just because someone is using these tires doesn't mean the tires are suited to the application. Watch some you-tube videos of people doing things that seemed a good idea at the time.
DW
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Stainless - you over wrote my response!
DW
Dan, My IP is faster than your IP, hey, racing is racing, what else can we do until the week before Bonneville when we start preparing the race car.... :roll:
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lammy...good luck with conti.!...you will have a hard time finding a tire manu that will give any tire test info....i bet the only responce you will get is "do not exceed our speed rating"...now most of us smart guys know that any kind of rating is only there for the amusement of the corp lawer but the SCTA has taken a firm stance on tire ratings... i think a good thing....
kent
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Clearly you don't want the body frontal area to be any larger than the largest thing in the bike. What's the biggest thing? The engine or you? Feet first would seem to have some aerodynamic advantages in a narrower front end. (At least, my shoulders are wider than my feet.)
Something I have not seen mentioned too much as regards the 'flat on your back' riding position is that, if you are the biggest thing (vs the engine), you need to be as flat as possible. Well, if you are laying flat on your back, I don't think you can see forward.
2 possibilities to overcome this come to mind.
First is a periscope prism/mirror arrangement that would allow you to see forward. Jack Costella had a periscope on one of his racers - so no new ground there. You're just going to have to design it to give wide enough forward vision to meet the rules. (FWIW, Jack told me he didn't like it.)
Second possibility is a video camera and flat panel display. Some of the human powered bicycle riders are using these on their fully enclosed bikes. You'll need some lenses to adjust for the short focal length. This has not been done in LSR to my knowledge, but I did float the question a while back. Response was 'we'll have to see it', but I wasn't shut down. Proof would have to be provided that whatever system provided ample visibility and (for me at least) had an automatic fail over. (going fast, screen goes dark, uh oh).
I can't address the issue of balance while lying flat on your back, might be interesting. Seems that the human head was designed for balance with the head upright - don't know how good the physiology is for head looking straight up. Certainly the mixed signals of ears say I'm going down, eyes say I'm going forward, would be an excellent recipe for vertigo.
Claustrophobic street luge anyone?
Thanks,
Jim.
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What happens when your video camera that drives the flat screen for front vision vibrates loose and falls off at 300mph?
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Pull chute, hang on, hope.
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What happens when your video camera that drives the flat screen for front vision vibrates loose and falls off at 300mph?
The human powered vehicle (HPV) guys can tell you all about how it works at 60mph, at 200 or 300mph I imagine the scrape marks are longer and deeper!
If you define success as not crashing, nobody has managed this successfully yet.
If you define insanity as doing the same thing over and over expecting different results, it would be best to learn from the mistakes of others before trying this lest people think your insane :)
I'm not saying it can't be done, but I've seen many HPV's try it and later cut a hole for a canopy, and they are operating in an environment where safety is often overlooked or taken lightly.