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Post by Mark Townsend on Jun 17, 2008 11:01:57 GMT
So I have my brushless, lipo powered carbon and titanium lightweight racing car. And half a ton of lead weights to make it back up to the BRCA weight limit.
Here's my crazy idea should we be looking at a lower weight limit in the future? e.g. 1400g or even 1350g not 1500g.
Remember all 'ideas' for rule changes happen at the BRCA AGM in October.
Do you think it's worth changing? You get to show off all your carbon again, less wear on your car and tyres, they'll be faster to boot.
Thoughts?
Mark
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Post by saintroeer on Jun 17, 2008 12:00:28 GMT
well as im aware that this year has kind of been a try it and see year with respect to the introduction of lipos and Brushless motors i would see that if they become standards for next year it would only make sense to raise the issue.
there will be arguments against lowering the weight but if all this time is going into designing top of the line cars with everything balanced and designed for speed and smooth driving only for us to add half a kilo of weight to where ever we can fit it to the car is pointless.
you raise it you got one vote.
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Post by yellowshark on Jun 17, 2008 12:18:02 GMT
Need to be careful here. You will force everyone to switch from NiMh to LIPOs and as we know the LIPOs are much more dangerous because they have to be enclosed whilst charging – not a good message to send to the outside world
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Post by lesbaldry on Jun 17, 2008 13:02:02 GMT
The majority of Nhims are very close in weight but Lipo's arn't,sticky weights will still have to be added ,my 3600's are half the weights of Nihms,the 4900's 120grams short..besides removing weight from that side of the car and it will upset the lateral balance,unless you redesign the chassis layout..all chasis's(unless sadle pack and one other make) at the moment are designed to carry Nims weight on one side or the other...just my thoughts
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Post by Mark Townsend on Jun 17, 2008 13:20:31 GMT
As I said it's just a crazy idea but with my low profile servo, lightweight lipos, tiny PT, and a nice shiny BL set up it seems madness to stick a church roof full of lead in the car. Maybe an extra lipo cell would counter the weight issue......................
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Post by lesbaldry on Jun 17, 2008 14:31:31 GMT
I too was fed up with the Zinc sticky weights so I found some box section alloy(B&Q,various sizes and shapes) and made some moulds to suit my needs,proper lead was used as this is more dense so you need less of it compared to the skicky Zinc strips,it can be moulded,shapped and worked with a rough file to whatever shape you want..Yes I know lead is toxic and great care should be taken with molten lead but I feel the effort was worth it.if any one wants to have a bash at making/moulding his own weights for the first time there are some important do's "n" dont's,speak to me first,Ill do my best to help.
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Post by keitheroonie on Jun 17, 2008 16:22:54 GMT
I'll have to add that lowering the weight limit would put many drivers including myself at a disadvantage, my car weighs 1540 with no weights added and thats with a lipo
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Post by chris84t on Jun 17, 2008 18:09:37 GMT
Wouldn't this hinder beginners at the moment, as lipo cells are more expensive? It might be a good idea for modified racers, but I feel that lipo battery's need a few years to get established before the rules are changed to suit lipo use. I haven't been in the game for ages now, but surly in stock class, cars should be made as cheap as possible to encourage new members? That being said there are price limits set by the BRCA on stock motors, why not on battery's too?
As for having to add weights, you don't see them when the shell is on So I don't see a problem there anyway, If you want your car to look [stupid expression]blinging[/stupid expression] in the pits why not just take off the weights when you are not racing?
Sorry if my opinions are misled as I say I haven't raced for ages.
I know that the BRCA should move with the times, and that technology is always changing, but I think it would be a bad idea to change the rules so drastically in such a short period of time. Having said that, in the future I should think that more and more people will start using lipo, I know I will as soon as I update my chassis and motor, but Not until I get established at racing again.
I hope I don't come across as too naive.
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Post by yellowshark on Jun 17, 2008 22:05:00 GMT
Chris I would question the view that Lipos are more expensive. Yes a single pack probably is but you have to look at the entire picture. You do not need as many. You could almost get away with one Lipo pack but certainly 2. For the last few racemeetings since Ross went over to Lipos I have been running the two cars on 3 Lipo packs. I would need 6 Nimh packs
You need 3 Nimh packs. I am sure 2 Lipos are cheaper than 3 Nimhs. Of course you have to add the cost of 120gm of lead weights ;D. Then there is the point that Lipos will probably last longer eg twice as long (not based on experience, just based on quoted figures for Lipos ie number of charges, vs how often our Nimh packs have gone duff). So now the cost disadvantage goes out of the window.
I have not done a thorough market survey but get the feeling that the price of a half decent Lipo charger is not any different to a half decent Nimh charger.
Then of course on top of that and the real winner for a beginner is there is zero maintenance; my view now is that all beginners should buy Lipo technology
So just rough figures
3 nimh at £40 =120. Twice per year over 2 years £480
2 Lipos lasting 2 years £100
Charger, well the cheaper version of the BC-6 is £50 I doubt you can get a comparable Nimh for much less. I am sure cheaper chargers with less facilties exist for both technologies
Then of course you have the optional extras
Lipo sack £10 Lead encasement for Nimhs £1250
There does not seem to me to be any contest here, except that perhaps the very top racers feel they can get a performance advantage from new Nimh cells - but they probably get 3 free packs new for every race meeting.
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Post by chris84t on Jun 17, 2008 22:24:32 GMT
You raise some very good points there, and have cleared up a lot of questions I might have had about lipos. It seems then that lipos are probably the best type of battery to use. If they are as efficient and cost effective as that then all we really need to do is wait for those using nimh to see the light!
I Think I need to update my equipment and see what is best for me, but for now I am stuck with what I have.
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Post by ukcmf on Jun 18, 2008 5:30:23 GMT
So I have my brushless, lipo powered carbon and titanium lightweight racing car. And half a ton of lead weights to make it back up to the BRCA weight limit. Here's my crazy idea should we be looking at a lower weight limit in the future? e.g. 1400g or even 1350g not 1500g. Remember all 'ideas' for rule changes happen at the BRCA AGM in October. Do you think it's worth changing? You get to show off all your carbon again, less wear on your car and tyres, they'll be faster to boot. Thoughts? Mark Hi Mark, My vote would be to move all classes with Lipos to 1400g inc PT. Col
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Post by lesbaldry on Jun 18, 2008 7:03:28 GMT
Unfortunatly no mater what we power packs we put in our cars they will still need 450grms/14ozs or so on one side for lateral balance,I cant see another way to get the weights off and keep the weight down without upsetting the handeling...thoughts anyone?
Take a 100grm or so off the battery side off your car and try and drive it fast,for sure it will be fast off the line but it will pull to one side under power"tweak" understeer one way and oversteer the other
Lipos are starting to become cheep,talk to Reality racing, Terry's found some very cheep packs ideal for new drivers and stock ...2800s about £28 I think
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Post by yellowshark on Jun 18, 2008 8:07:45 GMT
I think 1400 is too much. I am running 130 gms with 4900 Lipos. If I fit the fan I think that is around 20gms. I assume the 008 is one of the lighter cars out their, only becuase it is new, I could be wrong. My speedo is 18gms and there are plenty that come out heavier.
So I think going to 1400 would penalise those who cannot afford to change to ultra lightweight components. 1425/1450 would be better I suspect. In facr what we need is ht eLipo mnaufacturers to make the casings heavier!!
And Les is right on balance especilly with brushless which I understand is heavier. Oh my, that's it isn't it; I vote for an immediate reduction to 1400 in Stock ;D ;D ;D ;D ;D ;D
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Post by yellowshark on Jun 18, 2008 8:22:37 GMT
Oops sorry, I counted the weights on the battery pack and forgot the other 30gms or so on the chassis. So 1400 is more realistic. But Les's point on balance still stands
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Post by lesbaldry on Jun 18, 2008 8:35:37 GMT
Spot on in my veiw Pete,Its a shame there is such a variation in Lipo pack weights,the companys should get together and standadise pack weights for RC cars....Anyone got any Mercury or depleated Uranium ...Not only Lipo sack's but Bio suits and R.A.D meters in race controle to race....Blimey
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Post by Mark Townsend on Jun 18, 2008 8:45:53 GMT
The weight limit idea was aimed at a lipo class not to alienate the nimh class.
Another point about the beginner and lipo packs is the weight distribution. As Les says if you don't add weights the car will be unbalanced left to right. A nightmare to drive for everyone especially the beginners.
And it's not about bling it's about manufacturers spending millions of pounds developing super light weight cars and electrics just for us to stick a ton of lead in there. If lipo is here to stay maybe a design direction would be to move the positioning in the cars to attain an even balance without having to add quite so much lead.
The weight limit is set where it is because of the weight in previous years of the technology. With new technology should we be looking at a revised weight limit with a new layout?
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Post by lesbaldry on Jun 18, 2008 9:00:57 GMT
The weight limit is set where it is because of the weight in previous years of the technology. With new technology should we be looking at a revised weight limit with a new layout?[/quote
Nice thought Mark and Im with you but a rethink would make every car obsoleat and we will still have the pack variation weight problem...Phooooie to it... lets all go back to mini radio gear,Nhims and brushed,or lets dig out the track fill it with water and race model submarine's ;D
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Post by Reuben on Jun 18, 2008 9:40:44 GMT
for my first few weeks and still now, i am confused as to why people spend more money on "lighter" parts and chassis, only to slap zinc weights onto the car (seems a little expensive)
as it is, my car is underweight (weighs 1420) thats with a lipo (demon one, which is quite heavy compared to most of them), but i do have the smallest receiver EVER that came with my transmitter. but even with my old nimhs i was still slightly underweight.
as with balancing the design of my chasis means that there isnt to much trouble caused by the weight of the battery, as it lays accross the width of the car at the center point. infact all the lipo has done for weight is made the back end a little lighter so i can corner easier.
so is the dual deck design the future? with batteries being more central accross the width?
plus to the point on lipos being cheaper in long run. my first few weeks i was using 3 nimhs = £18 each = £54. but now i only run 1 5000mah lipo for the whole day = £50. plus i dont have to spend any time at home faffing with it. Plus it has given me greater consistency in lap times, with my last few laps not being noticably slower than the rest.
conclusion: ide be happy with a weight limit of 1400g, and Lipos are definitly the way forward.
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Post by Mark Townsend on Jun 18, 2008 10:21:31 GMT
Reuben, I don't know if you're entering the SL or STCC but they run the BRCA weight limit of 1500G so you'll need to get some (Race control have it) to get up to weight, especially with the lipo. It also helps balance the car left to right front to back to aid tuning.
Mark
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Post by lesbaldry on Jun 18, 2008 10:39:16 GMT
Weight will always be an issue,unfortunatly with brushless/Lipos at the moment we have light packs,large heavy speedos and slightly heavier motors so weight will always have to be added somewhere,its up to the individual to do the best he can. Droping the weight too low might be a little silly,the cars are too fast in some classes at the moment,the BRCA have tried to slow down one class by the use of 5 cells and some clubs run 19t 4 cell....even the 13.5s are balistic and no way are they an entry level motor,take 100 or so grames of this class and you will have a mod from a few years ago. some may argue lighter car less wear but also faster car more wear,swings and roundabouts?? A 1400 gr 13.5 car I think will be quicker than a 1500 gr 10.5??(on some tracks) At the moment 1500gr I feel is sensible and is there for a reason,Its easily achievable by 99.9% of racers and thier pockets with the present equipment,I expect this limit to be inplace for a while yet! I for one am thinking about runing 13.5 because of the speed/wear issue..Grey and Barry have already swapped...Plus my thumbs are getting slower
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Post by Reuben on Jun 18, 2008 11:08:37 GMT
Reuben, I don't know if you're entering the SL or STCC but they run the BRCA weight limit of 1500G so you'll need to get some (Race control have it) to get up to weight, especially with the lipo. It also helps balance the car left to right front to back to aid tuning. Mark done that last week, weighs 1500 exactly, without PT. but im thinking of getting some denser weights as it was hard to find places for them all to fit to make it balanced.
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Post by Robin Howett on Jun 20, 2008 13:20:18 GMT
We could try a club prostock weight limit of 1400g as this only effects a few drivers and would possibly save alittle on tyre/ component wear.
But the cars would be even faster - do we really need more speed! and the addition of 100g would be required for any big meetings so once/twice a month it would need a weight jig about.
We could but i'm not sure its worth the effort.
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