Clarifications to the GT12 Rules

[mark christopher]

Originally Posted by LongRat

Indeed, somewhat more. I run the Hobbywing sensorless setup, £60 for motor and ESC and an £11 2S LiPo. Any servo will work.
The main thing is that it will be so much less stressed on 2S. Although the 1S and 2S cars are similarly paced, 1S systems are pushing about twice the current which heats up motors and ESCs and kills cells quicker. I wouldn't be comfortable running one pack for a whole meeting on 1S which is my current practice. I am not arguing that it doesn't work, but it is wrong to exclude 2S as a confusion. Newcomers generally don't race at National meetings, nobody is getting confused about anything. The fact is, 1S should never have been started and from a purely technical point of view, it is 1S that should be banned and 2S only allowed if there's some sort of confusion to be avoided.

More rubbish
Mardave class was allways 4 cell nicad,nimh before it went to gt. Not 6 cell which would be 2s.

I did a 2 day national on one 1s cell, no performance change. Full entries of 1s cars at nationals shows 1s is the class...

[keenbutkrap]

go down the fusion exceed route £80 motor speed control combo buggy saddle packs 2 for the price of one 1s buy a fast servo off ebay job done works without a booster if it all goes ti-s up can buy a buggy for less than a gt12 and have some fun in the dirt without all this politics stuff i did and dont miss it at all all this petty rambling is taking the fun out of gt12 pick a system and someone will try and introduce a "better"one usualy someone who has deep pocket and little talent and uses deep pockets to win run what you want but make sure everyone runs the same try not to mix 1s and 2s it will end in tears

[mark christopher]

Originally Posted by RogerM

Oh dear, SOMETHING needs to happen as since the beggining of GT12 I've wanted to race this class, especially at my local club. However in order for me, and many many many many others I suspect, to take the plunge there needs to be a very clearly stated set of totally unambegious rules.

This is crazy! Please for your own sake, and that of the clubs, sort this mess out! I currently would rather do a 100 mile round trip to race a different class than go to a club less than 4 miles from my house to run GT12 as I KNOW whatever I buy will be the wrong damn thing in a few months time.

The class looks great fun, should be super close racing ... please don't kill it!!

You seem to be miss in formed, there are a clear set of rules for nationals, 1s 13.5 only, clubs may use 2s 21.5 at the clubs disgretion. 1s is here to stay.

The rules are set for gt class in April when the 12th section has its agm. Ie end of the 12th season.

[mark christopher]

Originally Posted by f888fhw

Understand what you are saying regarding the endbell, but i can say if it is blinking it is not actually stock.......

The motor list also has the line "If a model is chosen that does have a degree of mechanically adjustable timing it is up to the driver to prove that the timing is set to zero degrees"

To check a Speedo is in blinky mode you need to compare it to the list.

Do you know how to check your motor is in 0 timing without using the marks, there is a way

[RCMadShane]

Its all very well to say a club can do what it likes but in reality this is a bad thing, as we found out to our cost… People get a great boost by racing in a National event you get too see much more and really get a chance to spread out but if you do not follow the BRCA rule book then this is out of the question.. you then end up with those with money or who are sponsored who can and those who have to go it alone who can't..

I do not believe this should be the way of the GT12 class

You want to go pro go 12th or TC lets not be so tight on the GT12 otherwise there is no where for the young guns to start

[mark christopher]

Originally Posted by RCMadShane

Sorry guys I don’t know what the hell is going on.. This is the best way to kill a class before its properly established!!!!

This is the current rules on the BRCA website:…
http://www.brca.org/index.php?q=sections/subsections/pages/gt12-rules/13572
and it states...........
3 Definition of Brushless Motor
3.1 13.5 brushless - Any motor listed in any of the Electric Board Homologation List for Brushless Spec Motors (13.5) as updated from time to time.
3.2 21.5 brushless - Any motors listed in Appendix 3 to these Rules

Appendix Three – 21.5 motors allowed – (Construction) Rule 3.2
21.5t motors which have locked or fixed mechanical timing (ideally from the EB list) are suggested. For example:
HobbyWing / Xerun “Stock” 2.15t (part number 90040150/1)
SpeedPassion Ultra Sportsman V2 21.5t (Part Number SPF21V2)
SpeedPassion Ultra Sportsman V3 21.5t (Part Number SP00008)
Novak SS Pro 21.5t (Part Number 3421)
Losi Xcelron 21.5t (Part Number LOSB9409)
The Corally Pro Red motor is specifically excluded. If a model is chosen that does have a degree of mechanically adjustable timing it is up to the driver to prove that the timing is set to zero degrees.
(Intent – that the 21.5 motors are not used with mechanical timing advanced as this will give a performance advantage over the 13.5/1S combinations. It is intended that use of 2S cells simplifies installation, not gives a performance advantage.)
So to be messing around now is just taking the “p” people are buying kits for Christmas presents and they could end up with rubbish

So remove all that and everyone knows what to buy, job done....

[RCMadShane]

Originally Posted by mark christopher

So remove all that and everyone knows what to buy, job done....

I think not... Please show me where in the Rules (Link below) that it states that 21.5 is for club only??

http://www.brca.org/index.php?q=sect...12-rules/13572

[f888fhw]

Originally Posted by mark christopher

So remove all that and everyone knows what to buy, job done....

But what about the people that have already gone the 2s route!

Also from what i have seen 4 cell is a million mile away from 1s/13.5 so it should not be in the rules also then!

[SlowOne]

Steady Tigers!

1S systems do not put more stress on the motors than any other system. Whilst they have a higher current draw they have much lower revs. If you over-gear any motor on any system you will wreck it. On 2S, the motors rev higher putting higher mechanical strain on the parts. If you run 1S you put a higher electrical load on the motor. It's a trade of one set of strains on the motor for another. In both systems if you do not correctly gear a motor you will harm the rotor, but we have never, ever had a rotor explode on 1S whereas it has happened in 2S. I've never had a bearing replaced in a motor on 1S, but plenty were replaced at the Worlds on 2S. Different systems, different strains, different results, both able to toast a motor if incorrectly geared.

As for the cells you may think what you like but the facts are against you. Any 1S pack on the BRCA list will last you 200+ races or more even in a 12th Modified car before you could even call it tired. At club it will go even longer. Interestingly, the biggest growing electric classes in the last five years are the 1S classes - 12th, GT10, GT12 and F1 - in all corners of the world. If 1S was a cell-killer it would have got nowhere. You are entitled to your opinion, but for everyone else your summary does not reflect the facts.

Roger, I am sorry you find the Rules confusing. Here's it in a nutshell:

For National racing we run 13.5BL with 1S cells. For anyone organising meetings outside Nationals we have put in details of G2/4-cell and 21.5/2S to use.

The G2/4-cell needs no further clarification. For the 21.5/2S we gave guidance in two areas - a list of motors locked on timing so performance is closer, and using 'micro' 2S cells for which there is no BRCA list.

A car must be supplied as a rolling chassis, with wheels and tyres for £100. Whatever chassis comes with that car is what you use. If you want to modify the car and use a diff it races in GT12.1. If you just want to tune springs, dampers, etc. and run without a diff you can run on GT12.2.

Taking your point, I will make sure that such a summary is available on the BRCA website for 2013. I take issue with the 'mess' description as you are the only person to mention that since we started. I have had a lot of questions, but no one prepared to travel as far as you to avoid the class!! I'll try to make this a non-issue for you with the 2013 rules as I am mindful that you might be saying what others are only thinking!

To clear the rest up - we will have something on 2S classes more easily discoverable in the rules, and we will not be doing any more on bodies than presently in the Rules. Reverse can be discussed only if someone puts a proposal up for it, and the 2013/14 rules will be published next April after the EGM in early April.

If there's anything else, please come back an ask. It would be great if we could please all the people all the time, but we are realists! nonetheless, as I have said before, your feedback is appreciated and valuable. Please be part of any changes - things suggested on here will not make it into the Rules unless they are proposed at the EGM, discussed and voted on. Play your part to shape your class!

[RogerM]

That is the problem Mark, I'mmmissing informed, little Johnny who wants to start racing is alsommisinformed & his dad thinks "stuff this, a play station is easier" & yet another junior racer is lost forever.
Mardave's have always been a great place to start racing... until now it seem . :-(

[Dave Dodd]

Originally Posted by LongRat

Indeed, somewhat more. I run the Hobbywing sensorless setup, £60 for motor and ESC and an £11 2S LiPo. Any servo will work.
The main thing is that it will be so much less stressed on 2S. Although the 1S and 2S cars are similarly paced, 1S systems are pushing about twice the current which heats up motors and ESCs and kills cells quicker. I wouldn't be comfortable running one pack for a whole meeting on 1S which is my current practice. I am not arguing that it doesn't work, but it is wrong to exclude 2S as a confusion. Newcomers generally don't race at National meetings, nobody is getting confused about anything. The fact is, 1S should never have been started and from a purely technical point of view, it is 1S that should be banned and 2S only allowed if there's some sort of confusion to be avoided.

I use a core 45 esc on 1s using half saddles from my buggy, my 13.5 bl motor comes off track only luke warm, as the esc can only draw an average 45 amps whereas my 2wd buggy has a 150 amp esc on 2s which means its drawing 3x as much and twice the voltage..
....................

[LongRat]

Originally Posted by mark christopher

More rubbish
Mardave class was allways 4 cell nicad,nimh before it went to gt. Not 6 cell which would be 2s.

I did a 2 day national on one 1s cell, no performance change. Full entries of 1s cars at nationals shows 1s is the class...

Sorry man but 4 cell NiMh does not equal 1S LiPo. There is a +30% nominal voltage difference (4.8V/3.7V), which is the cause of the problems on 1 cell systems. The voltage difference between 6 cell NiMh and 2S is nominally only +3% which isn't a problem at all. The huge current and therefore significant voltage sag seen in 1S only compounds the problem, as Mardaves ran low power motors that never asked much of the 4 cell NiCds this issue never arose there.

These issues will not kill the class, it is too much fun to race for that. But you'll end up with a fixed elite doing Nationals with much less penetration from club racers wishing to give it a go. None of us have the full picture on what systems are used nationwide in GT12 clubs, but for sure there are many, many people using 2 cell LiPos.

[Dave Dodd]

Originally Posted by RogerM

That is the problem Mark, I'mmmissing informed, little Johnny who wants to start racing is alsommisinformed & his dad thinks "stuff this, a play station is easier" & yet another junior racer is lost forever.
Mardave's have always been a great place to start racing... until now it seem . :-(

Thats why it always best for little johnny and his dad to visit local clubs to find out some information and be guided to the right path.. but they may still go away and come with something entilely different from what you suggested..
mardaves are still a good place to start and most likely would have been 4cell - which as we all know is 1s.....
or Oval stock car/hot rod 6cell - 2s

[keenbutkrap]

little jonny goes to his local modelshop and ask what have you got not many will say mardave as for cost a 1/10 buggy ready to run is less than a mardave kit and can be run anywhere gt12 is now a racers class not a beginners

[Dave Dodd]

Originally Posted by LongRat

Sorry man but 4 cell NiMh does not equal 1S LiPo. There is a +30% nominal voltage difference (4.8V/3.7V), which is the cause of the problems on 1 cell systems. The voltage difference between 6 cell NiMh and 2S is nominally only +3% which isn't a problem at all. The huge current and therefore significant voltage sag seen in 1S only compounds the problem, as Mardaves ran low power motors that never asked much of the 4 cell NiCds this issue never arose there.

These issues will not kill the class, it is too much fun to race for that. But you'll end up with a fixed elite doing Nationals with much less penetration from club racers wishing to give it a go. None of us have the full picture on what systems are used nationwide in GT12 clubs, but for sure there are many, many people using 2 cell LiPos.

thats why 1s is for bl and 4cell g2.. 4cell powering a 13.5 bl is stupid quick.. TBH im glad i dont use cells anymore (all that charging and discharging got on my tits, havent the time) - lipos are brilliant
..............

i honestly havent spent a fortune on buying top gear, core esc, half saddles, dynamite 13.5 bl was even using a rtr servo up untill i crashed, so now have savox 1357.. 40 megs radio and pt ive had for 4-5yrs... im just an average driver, most of the stuff ive got is second hand
but i will be racing at the tamworth national on sunday, just for the experiance of doing so and no doubt i'll be in the bottom final.

[furball85]

also hotrods for 2013 are 1s, so are stockcars if running bl!!

[mark christopher]

Originally Posted by RCMadShane

I think not... Please show me where in the Rules (Link below) that it states that 21.5 is for club only??

http://www.brca.org/index.php?q=sect...12-rules/13572

exactly its not clear as the "club guide lines" are in the rules as an a apendix.

21.5 is NOT a national class

try reading the entry form, i have posted this before and Look at section 7 of the rules

http://www.brca.org/index.php?q=cont...onbridge/17800


Class Rules
13.5T brushless motors as per Electric Board list.powered by a 1S LiPo cell on Electric Board list. Approved ESC in “blinky” mode as per Electric Board list
Or
G2 brushed motor powered by 4 cell NiMh

NB 21.5/2S combination is NOT allowed at National level

[mark christopher]

Originally Posted by f888fhw

But what about the people that have already gone the 2s route!

easy, keep running it at thier club at club level and buy 1s if they wish to go to a national...

[mark christopher]

Originally Posted by RogerM

That is the problem Mark, I'mmmissing informed, little Johnny who wants to start racing is alsommisinformed & his dad thinks "stuff this, a play station is easier" & yet another junior racer is lost forever.
Mardave's have always been a great place to start racing... until now it seem . :-(

it still is, you just need to make sure you have the correct info, as i did, i emailed the 12th officials who were more than willing to ensure i got the correct facts in my head, the reason i "seem to know" about this subject is because i took time to find out and spent time chatting to pete winton (slow one)

[mark christopher]

Originally Posted by SlowOne

Steady Tigers!

1S systems do not put more stress on the motors than any other system. Whilst they have a higher current draw they have much lower revs. If you over-gear any motor on any system you will wreck it. On 2S, the motors rev higher putting higher mechanical strain on the parts. If you run 1S you put a higher electrical load on the motor. It's a trade of one set of strains on the motor for another. In both systems if you do not correctly gear a motor you will harm the rotor, but we have never, ever had a rotor explode on 1S whereas it has happened in 2S. I've never had a bearing replaced in a motor on 1S, but plenty were replaced at the Worlds on 2S. Different systems, different strains, different results, both able to toast a motor if incorrectly geared.

As for the cells you may think what you like but the facts are against you. Any 1S pack on the BRCA list will last you 200+ races or more even in a 12th Modified car before you could even call it tired. At club it will go even longer. Interestingly, the biggest growing electric classes in the last five years are the 1S classes - 12th, GT10, GT12 and F1 - in all corners of the world. If 1S was a cell-killer it would have got nowhere. You are entitled to your opinion, but for everyone else your summary does not reflect the facts.

Roger, I am sorry you find the Rules confusing. Here's it in a nutshell:

For National racing we run 13.5BL with 1S cells. For anyone organising meetings outside Nationals we have put in details of G2/4-cell and 21.5/2S to use.

The G2/4-cell needs no further clarification. For the 21.5/2S we gave guidance in two areas - a list of motors locked on timing so performance is closer, and using 'micro' 2S cells for which there is no BRCA list.

A car must be supplied as a rolling chassis, with wheels and tyres for £100. Whatever chassis comes with that car is what you use. If you want to modify the car and use a diff it races in GT12.1. If you just want to tune springs, dampers, etc. and run without a diff you can run on GT12.2.

Taking your point, I will make sure that such a summary is available on the BRCA website for 2013. I take issue with the 'mess' description as you are the only person to mention that since we started. I have had a lot of questions, but no one prepared to travel as far as you to avoid the class!! I'll try to make this a non-issue for you with the 2013 rules as I am mindful that you might be saying what others are only thinking!

To clear the rest up - we will have something on 2S classes more easily discoverable in the rules, and we will not be doing any more on bodies than presently in the Rules. Reverse can be discussed only if someone puts a proposal up for it, and the 2013/14 rules will be published next April after the EGM in early April.

If there's anything else, please come back an ask. It would be great if we could please all the people all the time, but we are realists! nonetheless, as I have said before, your feedback is appreciated and valuable. Please be part of any changes - things suggested on here will not make it into the Rules unless they are proposed at the EGM, discussed and voted on. Play your part to shape your class!

cheers pete did not want to start pointing him towards the correct lipo/motor facts too, knew you would get here in the end