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MG Midget and Sprite General - rocker box racer

I am making good progress with my challenger although to get everything within the regs is proving just about possible

Anyone getting near complete?
Robert (Bob) Midget Turbo

Having trouble finding the loophole?
Trevor Jessie

LOL
Robert (Bob) Midget Turbo

During a recent garage tidy-up, I unearthed a couple of spare 'bodyshells'!
Dave O'Neill 2

Greasy palms can make just about anything legal.

Nice one trevor..... i needed that laugh, thanks

Prop
Prop

G'day Robert,
Once you get started it's all down hill.;-)
Is it a cut down MGC rocker cover.:-/
Don't they allow Austin tappet covers.:-(
All new vehicles must be fitted with air bags.8-/
Correct engine colour, I like Longchamps green.:-p

I'm only jealous of the fun you will be having.
Regards Phil the Dill
PRC Cuthbert

look out for my mate's, I'm SLICK-50 ing the tyres on it

you'll recognise it as it'll be the one that just by a small margin wins every heat and the Final

plus of course it'll be the only one with an owners Handbook (and revised for steering column)
Nigel Atkins

what are the rules on moveable aero, tyre changes and KERS?
Rob Armstrong

The rules are very strict and very limited, ie no movable devices!

However I hope like every other engineer I can find little areas where gains can be made. Within the rules of course!

I have identified 3 areas where I think gains would be made if Adrian N were competing.
:)
Bob Turbo Midget England

I think that perhaps the most important thing that one can do for their rocker box entry is to actually purchase a ticket for the event - after all, without that you will NOT be allowed to enter :)

Aside from this, I am stating now, that I am NOT going to get involved in the rules - the rules are the rules, and they have been agreed and passed by the Chief Scruitineer - who is an excellent engineer, so, if he says they are fine - then they are fine .....
rachmacb

Where or where can the rules be found !

Not obvious to me on the M50 web site or have I missed the vital link.

I have set aside a whole hour tommorrow to build mine !

R.
richard boobier

Thats strange?
I downloaded the regs of the site some month or so ago yet now they have disappeared

I am hoping the worst will not be happening?
Robert (Bob) Midget Turbo

I looked yesterday and couldn't see anything.
Dave O'Neill 2

If it is any help Rich these were the critical stats

Max wheel dia 6 inches
Max width of car also 6 inches
Nothing to protrude beyond the rocker box front and rear.
I have forgotton the max weight?
Finally no metal contact with surface ie no metal tyres.

Got the rules at work so could check maybe monday :)
Robert (Bob) Midget Turbo

Max weight - that is my Adrian N dark horse - need that most of all !! (along with my carbon fibre spoilers !!!) not to mention trick rear wing/end fences and DRS.
The zero friction wheel hubs have caused hours of debate @ the pub - ptfe/micro ball bearings/polished plastic plain hubs with teflon lub - oh for testing time !!!

R.


richard boobier

Ah Bob..

Because its you...

http://midget50.com/downloads.html

(They were published under the news section - there has been so much news that it has dropped off...)
Toby Anscombe

Thanks Toby :)
Bill 1

Thanks Toby.

The one thing that I would like clarification on is...

"If the wheels of the car cross over the line marker, the car is disqualified."

What is the line marker and how are you supposed to stop the car from crossing it?

It would also be useful to know details about the length and incline of the track.
Dave O'Neill 2

Thanks Toby,

Adrian N is too busy at Barcelona to help this weekend so lowers my chances - LOL.

R.
richard boobier

There shouldn't be a line marker on the Midget50 track.

The rules simply allow for compliance with other tracks that have painted lanes.

Ours has lane fences I understand.

Pictures are around someplace.

(How to stop running over? Presumably by making it with very accurate running gear. I wasn't ever very sure) :(

The length of track is about 24 feet, I understand it has been built on three eight by four boards. How that translates metrically I am at a loss to know. I don't buy eight by four boards.

I don't know the inclination of this track, not seen it yet, though some of you may have as it is owned by the Austin Healey Club and had been used in events by them.

They have kindly loaned it to us for the event and the same track is expected to be used at MG Live for the follow up event.

I hope this helps you all.
Bill 1

Watching U-tube videos, the commonest failure of many of the faster cars is disqualification after veering off their lanes. Clearly wheel alignment / self steering design is the key to success.
Guy

Guy it sounds as if our regulations person got it dead to rights then


:)
Bill 1

David I asked the same questions a while ago and subsequently the answers were posted onto the site here. and have been for a while

http://www.midget50.com/tja.php

Seems like some committee do not watch the site LOL.
Robert (Bob) Midget Turbo

OK - yet again, it is necessary to point out that it's a tad ungracious for people to attack members of the Midget50 committee, when there was a general call for ANYONE to put themselves forward and help at this event - which is for the general Midget and Sprite community, to be held in a spirit of friendship and fun.

Sadly, once again, it is the rocker box racing that is causing most of this bitterness and ill-feeling.

I am here, mostly under my own steam, and, believe me, I've counted to approx 1 million - VERY SLOWLY - before I write this ....., so, before there are any further bad comments towards ANY member of the Midget50 committee - please remember that, without them, none of this would be happening, and there wouldn't be several hundred tickets sold - and a mass of people looking forward to the event from ALL AROUND THE WORLD.

On the subject of Rocker Box - to make it abundantly clear, since it became "my baby" - the RULES as they are are the STANDARD rules which are taken from many governing bodies of Rocker Box Racing - on an international scale, and, therefore, if you have a problem - take it up with them!

Secondly, they have been checked over by the person I have requested does the Scrutinering on the day. This person is a qualified engineer, as well as a well-respected member of the MG world - and will NOT be there for any abuse as they have kindly volunteered their time for YOUR ENJOYMENT.

Thirdly, the ramp is the property of the Austin Healey Club - so, is not there to be insulted or criticised in any way. It was kind of them to let us - and then MGLive - borrow it, and, as is CLEARLY STATED IN THE RULES "The ramp is the one provided by the organisers" - as such, it will be as it is on the day - and that is FINAL.

It is up to each individual to check the rules - which have been kindly uploaded again - and to make their rocker box racer fit within the rules. If you do not do this and rely on other peoples' interpretation of the rules, then this will NOT be an excuse if you are spun out of the competition at Scrutiny.

Sadly, I noticed on another thread, that many of you have complained about the committee in the past - but NO-ONE has actually said thanks for any of it.

I, for one, did NOT join the committee for thanks - but to make the best day possible - and the day before with the link up with Lincs MGCC Autosolo - and the cheap entry to the Museum - but, perhaps those who criticise first and loudest - might like to think about taking up the organisation of Spridget - and then Midget - 75!!!!!!!!!!!

Sorry to be blunt and direct - but, it would be nice if Rocker Box racing was not turned into something nasty and took away the general fun of the day.
rachmacb

Sorry Rachel - Over reaction alert!

I don't read any criticism of the plans, rules, equipment or committee. Just the normal easy chat and divergent views that appear on any subject on the BBS.

I am looking forward to seeing the entrants to this event. Should be a fun part of the day!

Guy
Guy

Where abouts is there aggro about rocker box racing? I thought it very good that people are interested and are building a car.

Personally if I were organising an event I would love enthusiasm and questions from those who are keen to enter.

I am with Guy What is the problem?

Who has expressed that they have a problem with the rules?? They seem fine to me and everyone else I have seen post?
Robert (Bob) Midget Turbo

Seems to me that some folk have very short memories - but if we are all only intending to have a good time - then get on with building them and getting cars ready for it and everyone shall be happy :)
rachmacb

I wouldn't have dared post my comment above for Rachel, except as I gather it is the End of the World I thought I have nothing to loose.

PS Thanks for all your hard work Rachel, we all love you really!
Guy

Oh dear Guy - didn't you hear - it's been moved to June 12th and I'm your guardian angel ....!!!!!!!!!

Safe driving down :)
rachmacb



I also haven't noticed anyone criticising the ramp, or the rules...only that there didn't appear to be any rules on the website.

It's very difficult for people to "check the rules" when they can't actually find them.
Dave O'Neill 2

What criticism ?

I only wanted to find the rules so I could have a go at building a fun toy - if its causing this sort of concern and aggro' I for one am rapidly loosing interest and probably won't even bother to finish it.

I also thanked Toby for reposting same.

To be topical - lifes too short !! or so they say !

Yes I am very greatful for everyones hard work - its logistically impossible for some of us to get involved etc.

I sincerly hope everone is only hoping for a fun day to meet old friends and make new ones etc.


R.
richard boobier

Keep building Rich
I want to see your version of the Adrian car, preferable the Webber version LOL.
Robert (Bob) Midget Turbo

Chaps I should probably point out that most of the committee do not watch the BBS. Rachel does and has made a fine job of keeping you informed and acting as a pathway to questions you may have raised.

Some committee members would be hard put to actually find us in here.

I couldn't find the rules on the link Robert posted, it has track info but not the rules you all wanted, on that page. Maybe my cache has lost them by now, I am not racing rocker boxes in June.

Nice picture of the track though. :)

Anyway, thanks to Toby keeping track of "news" changes he was able to restructure the website to have the rules in the "Downloads" section for future reference.

Thanks for helping us keep track.
Bill 1

blimey take a chill pill rachel. You should know my now to take Bob's off the cuff comments with a pinch of salt. I believe they come across in a slightly different way than in his head.

anyway, who ever heard of a committee not getting heat from time to time? If you can't stand the heat .... !!!
Tarquin

Aha

I knew I had little comooot-ability

Found the newly updated extra RBR downloads page "off" that one

cheers Bob
Bill 1

Dare I have a discussion with friends about Rocker box construction?
I think I will risk it. :)

Have a read of the rules please anyone and see what you think.

The rules state maximum overall length is the Spridget rocker cover. Do the group think that means that the rear wheels must NOT extend beyond the rocker cover? Thats what I think?
Robert (Bob) Midget Turbo

Bob,

Your best bet is to talk to Charlie Whiting.
He'll be in Monaco from friday morning until late sunday!

Alternatively, the Pirelli bloke may be able to help you but be warned, Charlie has told him not to supply rubber that lasts the full race length.

Peter
PJ HOBSON

The wheels must not extend beyond the FRONT of the rocker cover.

Nothing can extend beyond the FRONT of the rocker cover.

Overall length: Midget rocker cover with no overhangs.

This is how I see it...

If a 1500 rocker cover is longer than an A-series, the rear wheels can extend beyond the rocker cover as long as the overall length is not more than the length of the 1500 rocker cover...and vice-versa.
Dave O'Neill 2

And the world call the US a litigious society.

Perhaps rather than enter law school in America this fall, I should consider persuing a career as a Barrister in the UK!!

Phil, "I agree with Dave's interpretation, That'll be 100 quid please"
Phil Burke

Bob, you better sand the front and back edges of the cover back to bare metal. You wouldn't want to get disqualified for the extra length added by a coat of paint.
Guy

Guys, this doesn't take "rocket science" to build a nice rocker box racer but it does help.
My advice based on actual racing experience,
Strong axles that won't bend and alter steering.
Adjustment for steering corrections. Must be easy to adjust and lock into position. Most events will allow some testing time before the actual racing begins.
Very good bearings, low friction. If using sealed bearings, remove seals and wash out grease and replace with light oil for minimal drag.
Low friction tyres, large O-rings work well if you can fabricate or find narrow pulleys to fit for wheels.
Weight, maximum allowed is desirable, but test if you can. More weight means more friction on the bearings, so it's a matter of balance.
Adding a bit of style and flair doesn't hurt. Racing numbers or other bits add to the look.
Make the front tyres exactly even with the front edge of the body, meets the rules and allows easy alignment of the car to the track as the nose and both tyres will touch the starting gate at the same time automatically aligning the car.

B Young

LMAO - my advice - to READ the RULES!!!!!!!!
rachmacb

We have read the rules?
What is your opinion then Rach?

The rules state nothing to extend beyond the Rocker box. So that is easy but the inference is different.

I think to be sure I will email the man who knows. Simples :)
Robert (Bob) Midget Turbo

Email whomever you like - all the details are in the rules - and they will be the ones that are used ... SIMPLES

Since you obviously didn't take the hint at Belton, then, there's nothing further I can say :)
rachmacb

I am not sure what the problem is Rach? but if you can not suggest what the correct interpretation of the rules is then please refrain and allow those who are interested in making positive contributions do so. Thank you.

Refering to "Dave O" does anyone know the length of a 1500 rocker cover?
Robert (Bob) Midget Turbo

For the FINAL time - these are the CRITICAL DIMENSIONS for the Rocker Box Racing.

Overall length: MIDGET Rocker Cover - with NO overhangs
Overall width: MIDGET Rocker Cover to the Maximum of 15.25cm
Overall height: MIDGET Rocker Cover to the Maximum of 10"
Maximum weight: 2.75kgs (6.1lbs)

ALL racers WILL be checked prior to racing.

ALL entrants MUST have a ticket for Midget50 - and this also will be checked

Judges decisions are FINAL
rachmacb

Guys, be careful of getting them too low. I've seen cars that would scrape the bottom on uneven portions of a track and that would slow them or cause them to veer off course.
B Young

So was I right the first time?

The rear wheels are the same as the front and can not extend beyond the rear/front flange of the rocker cover?

Not sure of the need to become aggressive?

Rach by the way I will enter Midget50 as and when I decide which vehicle to bring and if I can construct a racer before any deadline.

For my benefit does anyone here believe that I have been argumentitive on this thread? I personnally thought we were having a conversation about rocker box racing and I have helped some find the rules which has highlighted the fact that the rules had fallen accidentally from the site. That can only be good can't it?

Not sure that I should be reported to anyone?
Robert (Bob) Midget Turbo

Argumentitive? I don't think so.
Dave O'Neill 2

Bob,
I reckon you have found the loophole! The rules say no overhangs, but my interpretation of the word overhang is not the rear wheels extending beyond the length of the body but the body extending beyond the wheel with the proviso that the overall length is not greater than a Spridget rocker cover. Thus it does seem you could base your dimensions on a 1500 cover but have the body of an a series with the rear wheels sticking out a bit.
However, would it make a difference?
It might be worth a try just to carry on this merry banter on the day. If the rule makers don't want a degree of interpretation then they should make the rules watertight and crystal clear in the first place but where would be the fun in that? I think some people seem to have lost their sense of humour!
Rules are there to be bent to just before breaking point! If not Colin Chapman wouldn't have bothered!
Matt1275 Bucks

This seems like fun!




I'm glad I declined taking this on.

Like anyone considering this FUN pastime I looked at the rules and they seem very simple and straightforward.

The Midget came in two flavours so there are two basic items to build the "racer" from, 1500 Triumph based valve cover and the BMC A series cover.

Whichever unit you use surely the length of your "racer" has to be the length of the cover you use. Including the wheels in overall length.

In building the wheels/axle you have the allowed width of 6" / 15.25 cm but they must still be within the length of the "body".

Bob's question "The rules state maximum overall length is the Spridget rocker cover. Do the group think that means that the rear wheels must NOT extend beyond the rocker cover? Thats what I think?"

That's what I think too...

LOL Bob since Rachel IS the authority with regards Rocker Box Racing at Midget 50 who do you think she is "reporting" this to?

And yes we are grateful that you and Richard helped bring the loss of the rules section from the website to our attention.

Ta.

Richard, I hope you all do bring racers, if I can find some time I'll pop across to see them.

Lets face it, this is all for fun, only two weekends to go before the big day. Don't forget your balloons :)
Bill 1

""Whichever unit you use surely the length of your "racer" has to be the length of the cover you use. Including the wheels in overall length""

A very factual statement Bill and thankyou for clarification as you will see there are a number of other interpretations, what is so difficult in simple explanations?

If I have been causing trouble for anyone then let me apologise it was certainly never intended? However if any of this is trouble then you want to try racing in a RACMSA championship now that is trouble.

I had a car and wanted to modify the front roll bar. The rules "clearly" stated "front anti roll barS are free"

I made a duplex front anti roll bar for my car. After another couple of races that I won (that is always the problem, if you lose no one cares what you do LOL) the technical rep approached me with a complaint. he said the following:

"We meant that the front bar could be replaced by a bigger diameter bar, not by a duplex!"

I pointed out the statement "front anti roll bars (plural) are free" this did not go down too well. Anyway rather than allowing the RACMSA to resolve this matter I removed the second bar simply for peace (I am that kind of guy)

Still won the championship and caused a number of others to remove the duplex bars that they had copied!

Sometimes you need to laugh!
Robert (Bob) Midget Turbo

No worries Bob

I think ARBs will be free here but remember the weight factor

:)

Bill 1

The catch is usually there in that well used phrase "the judges decision will be final". Which I think means that whatever discussions and opinions may have been expressed before the event, on the day a specific rule just might be interpreted in a way that wasn't expected. But maybe that is just a part of the fun and of the risk of competition.
Guy

Guy - as much as I share your twin - if you poo stir anymore I will make you wear the orange cap of shame all day if you aren't careful!!!!!

However, there was a good point in there, although nope - they won't change in some bizarre manner on the day!

Thank you Bob for the apology - we look forward to your entry and wish you -and all the other racers - the best of luck. :)
rachmacb

Rach,
I am not s%*t stirring. Nor am I saying that new rules would be unfairly introduced or interpreted on the day.

What I mean is that if one chooses to enter any competition part of the fun is in working out how to interpret the rules to give oneself an edge, and part of the risk is that the judges may take a different view! It is rare indeed that a set of rules can only be interpreted in one way, which is why the phrase about judges' decision is usually included.
Guy

Ahhh ok - sorry - misunderstood what you were getting at and yes that's normally why it's included I've found - of course, when I was younger if we ever questioned judges, we couldn't sit for a week!!!!
rachmacb

Rach, no no no

The orange cap of POWER not shame

I expect mine will vanish during the day rather like my Yellow one did at Gaydon...

I wonder where THAT went?
Bill 1

Heh - far more fun to watch this from the sidelines..

At least someone gets it (thanks Guy!)

"What I mean is that if one chooses to enter any competition part of the fun is in working out how to interpret the rules to give oneself an edge, and part of the risk is that the judges may take a different view! It is rare indeed that a set of rules can only be interpreted in one way, which is why the phrase about judges' decision is usually included."
Toby Anscombe

I still don't understand why Bob has to apologise for someone else taking his comments the wrong way!
Tarquin

Tarquin, your married, of all people you should know men always have to apoligize to women.
Doesnt mather if youve done something wrong or not, its just how women are. ;)

I think for your comment and taking Bob(R) side you should apologize to Rach. :)







Arie de Best

Is that why you're still single???

go paint some houses!

Tarquin

>>> Is it a cut down MGC rocker cover... <<<

Or NOT cut down... you could make a nice little bus out of that! :-)

By far, the most imaginative rocker cover racer I've seen was the "Shock and Awe" entry that showed up at MG2003 in St. Louis. It looked fairly typical on the outside, but its designer had concealed within a clever device with a roller ramp and an iron wedge. While on the starting ramp, the wedge would remain in place due to gravity, and provide extra weight to speed the racer down the ramp... but when it reached the level at the bottom, the wedge would slide out the back, lightening the racer up for the coast to the finish. We were all impressed, although the owners of all the racers it defeated might have had reservations about how they'd been outfoxed.

Here's a pic of Shock and Awe on its ramped display stand. Note that if it were level, the wedge would roll out the back:


Gryf Ketcherside

Preparing for a race, its designer lifts the hatch in the rear to fit the wedge:


Gryf Ketcherside

And following yet another victorious run, here's the discarded wedge on the racetrack.

Maybe some of you Midwesterners can remember the name of the designer/builder. I thought I had a pic somewhere showing the internal setup of this thing, but I couldn't find it.

-:G:-


Gryf Ketcherside

To determine the parameters to which the said vehicle, namely Bob's racer, should be presented to the scrutineers.

It would be helpfull if the scrutineers had a wooden template 15.25cm wide and whatever length the rocker box "pressings" are supposed to be. If your motor does not go inside it, it ain't racing.
A flat plank and a height template set a 10" seems to be the other physical perameter needing a check.

I will bring my junior hacksaw, and, numerous blades for those unfortunates caught out trying to do a 'chunky Chapman' on the scrutineers!

Bob, I hope you clean up!!!!

Peter
PJ HOBSON

On that Peter - already been planned ;)

The scruitineer also has declared wedges etc ARE moving parts and not allowed!!!!
rachmacb

No doubt practice demonstrated that The Wedge worked. But why? Surely the linear momentum as the car reaches the bottom of the slope is best maintained by keeping the mass of the wedge travelling with the car. (momentum = mass X velocity) So long as the weight remains within the set limit
Guy

<<The scruitineer also has declared wedges etc ARE moving parts and not allowed!!!!>>

Are wheels classed as moving parts? Are they allowed? ;o)
Dave O'Neill 2

Steady Dave you will get me into bother again :)

The most sad thing in all of this is that I was trying to get my racer looking better for the POO competition. If I could have extended the wheelbase slightly my car would have looked so much better. However my question was interpreted as some sort of devious messing in an attempt to gain some advantage!!

Better still it has prompted discussion that hopefully has brought the event to the fore and hopefully encouraged others to build and have a go!!
I really hope so.
Bob Turbo Midget England

Guy, your logic is sound, but you forget the factor of increasing the rolling resistance to the tyres and bearings that the weight adds. As I mentioned before, weight is sometimes best for a particular rocker box racer when it's not at the maximum allowed by the rules but rather the best compromise between acceleration on the ramp and rolling resistance on the rest of the course. You also need to consider the smoothness of the course. I've raced off plywood ramps that ended in a course marked out on the asphalt and on fully decked plywood courses. The heavier cars seem to have a bit of an advantage on the rougher courses as they are less prone to being knocked off course by the rough ground. Rachael, what type of surface will they be racing on?
Dave, just to be on the safe side of the scruitineer you should build your car with runners like a sled instead of wheels. ;-)
B Young

Did some test running today.

Tracking the racer so that it stays straight for an extended run is proving extremely difficult, wondered how others were performing?

Rach just a quick one please

How high is the partition between each lane?
Robert (Bob) Midget Turbo

Bob,

Been away so only had a couple of hours today to put it together - working away next week so no more time - its a Rat racer (very rough finish !!!).

Are you sure pre season testing on private tracks is permitted - Max doesent like it !! LOL.

Will need fettling in the pits !

R.
richard boobier

Ok for the avoidance of any doubt that I am withholding any information - the ramp is the property of the AH Club, and, as such, I do not know anymore information than you do! This was why the rules stated that "the ramp will be that provided by the organisers".

I hope this is taken in the spirit of helpfulness and friendship after all the cr@p that has gone on.

As for the POO - this is being judged by member of staff of Burghley House :). Therefore, it has to be within the rules of the critical dimensions, but anything goes.
rachmacb

Bob,
Try a bit of sugar on the front wheels. That should help.
Guy

Bob,

Re-reading your post about tracking problems - is your front tracking not ajustable ? All Midget need 1/8th toe in its in the handbook !

Mine is (with a BBH)!

R.
richard boobier

No problems Rach, Is it possible to ask them please?
What crap?

See what you mean Rich I was running parallel!

Must get that copy of the owners handbook. LOL
Robert (Bob) Midget Turbo

I hadn't noticed any carp, either.
Dave O'Neill 2

Lol Bob no I'm afraid it isn't!

I'm not being rude or awkward, but, aside from anything else there are two very good reasons and that is my final decision.
rachmacb

Rich sorry to inform you but have painted my racer today. :) Maybe my effort wont be faster than yours but it looks better.

Decided to mount my bumper bar about 2 inches high incase the dividing wall is not very high. Jobs a good un!
Robert (Bob) Midget Turbo

Just finished my racer and thought I would check its weight bearing in mind I was keeping it light I was staggered to find it weighed in at 2.4KGs max is 2.75KGs so in spec but closer than I expected. :) Must be the boot rack that was heavy LOL.
Robert (Bob) Midget Turbo

This thread was discussed between 17/05/2011 and 09/06/2011

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