LiPo packs and overall weight .....
 

A post on the MK GP thread about weights got me thinking about this so I thought I'd start this poll to see what the world at large thought .......



So what do you think about forcing LiPo runners to add at least the amount of weight that would be required to make the combined weight of the Lipo pack and it's ballast say the same as a pack of 3700s????
(purely from the point that would be the minimum cell likely to be powering a quick brushless equuiped car)

Based on that post Cosie tells me his S2 with LiPo in weighs in at 1525g (still loads above the BRCA minimum 2wd weight so no probs there) and I stated that my RB5 with 4500s in will be nearer 1700g .......

Now to save the brain cells (I know some are running low on those as S.A.D. takes it's toll) that is 11.5% extra my poor motor has to accelerate out of each and every high grip / low speed corner and punch across the jumps too.
Now I could make that up by driving 11.6% better (but I'm not going to count on that too much!!!).

So here's the point (finally you all cry) .......

If Cosie's Lipo pack weighs in at 150g less than a pack of 3700s and my 4500s tipped the scales at 25g (guessed difference) over the 3700s BUT the rules stated that he had to make up the difference in ballast on / under the LiPo pack IN ADDITION to any weight on there for handling reasons it would level the playing field again .....

That would leave me with some choices to close the gap, dremel, run 3700s, buy loads of light weight bits-and-bobs, go and have a cup of tea and not worry about it!

Does that make sense (as far as the question is concerend)??????

I know there would still be those that say what about the 0.4V nominal voltage increase etc. but lets be honest ..... for anything much quicker than a spec the extra voltage isn't going to matter a jot. In fact most modern NiMh cells run about 1.23v anyway so that's 7.4V!!!

What is it about 'the whole Lipo thing' you don't like? :confused:

I'd say that if you choose to run NIMH in your car and I choose to run lipo in mine, as long as mine is still above the weight limit then that's fine. I honestly can't see why anyone would want to run NIMH when the chances are the availability of good quality packs will be in short supply as they have been for a while and also the lifespan of the packs is terrible. Almost everyone I know has had problems with cells going down in packs over this last season and the problem will only get worse as more and more cell distributors go over to lipo....... of course, this is just my opinion :)

To be honest I would say that this would be extremely hard to police and would not be viable. Different cells from different manufacturers weigh different amounts. You could be faced with the prospect of setting the weight limit using GP 3700's but what if someone were to run Intellect 3700's ?Scrutineers would also be faced with the prospect of asking every racer/mechanic to remove their cells from their car to weigh them along with weighing the car & cells. It can get frantic during scrutineering as is

I fully understand your point though

as long as the "lipo"car is the minimum weight, there is no problem.

Use Lipo's or use Ni-Mih, the choice is yours - if you don't want to, don't try to suggest others should compensate for your whims. The Lipo bashing is growing a tad tiresome now.

everyone will have to run to minimum weight at nationals any way, so wont make any difference, lipos are ace, and like garlic bread they are the feature,i think a more sensible poll or question would have been why wouldn't you run lipos,and the way they deliver power is miles better than nimh,we were running 6.5 last week were before lipo it was almost always a 5.5,less heat less stress less wear,

Well said...... new technology is good for everyone I think. I remember people knocking 2.4ghz and then the same with brushless. :)

.... garlic bread is the FEATURE :p

I'm with Alex - so long as the car weighs at or above the BRCA minimum limits, then they comply to the prevailing regulations - be they either LiPo or NiMh powered.

There are (as I'm sure we'll all learn soon enough) plenty of situations where the known but comparatively heavy configuration of a NiMh car will be easier and more forgiving to drive than its LiPo counterparts.

Come the 1st national in 2009, if the conditions get slick or bumpy during the day, I'm sure there will be plenty of newly LiPo converted runners who'll be busy adding weight to their cars just to get the handling balance back to something more normal that they're more used to - and lets not forget that 8mins of practice isn't a great deal of track time to start trying to learn how a new car or weight distribution really works.

Besides, I've got no idea where I can put 170g's worth of ballast in my 4WD:woot:

My personal experience:

My trakpower packs weigh roughly 4 sub c's so when i first ran my X6i put two infront of the lipo to simulate 6 x sub c's - the car wasn't that great, but was superb with the LIPO alone..I run no ballast. There are few folks that disagree but my last result at worksop showed that it suits me personaly..

I have a lipo cat and a nimh one, they both feel pretty similar. The LIPO perhaps feels better indoors as its a bit more snappy, all i've done to it is add 15g on the rhs to even up weight distribution L to R..

I'm not really worried that i'll have to bring the cars up to weight for Nats, i can just play about to find where it goes best.

Valid question .....

I personally don't like the way they deliver their power, but that's my own opinion based on what I like. I plan on staying with NiMh for 09.

The main issue for me is the one this poll is based on .... how to level the mass based issues between NiMh and LiPo racers. More mass is bad in both the breaking and acceleration zones ... the two places where most time can be found on track!!!

The other thing that worries me a little is the abusive charging / handling issues. Somebody will do something stupid with LiPo and set the damn thing on fire, worse case taking a sports hall with it on a club night. I know that the serverity is no greater than a NiMh blowing up (some would say more confined so maybe even a little better) however little Jonny is unlikely to have IB4200s or any of the other suspect cells and also unlikely to be trying to charge them at 1,000,000 amps. What I am trying to say is those that are at the most risk from blowing up a NiMh are unlikely to actually achieve it.

That said, if all the shops are responsible and explain why it is a good idea to always charge in a quality sack, not abuse the cells and only provide quality equipment then I can not honestly see a problem with LiPo safety.
The problem will come when they filter down to the mail order catalogues, Argos etc. or even those local model shops often staffed by people who can barely grunt their name let alone provide good quality advice to a noob.
It's not the experienced racers and quality race shops that worry me with LiPo, it's little Jonny who shops at "Neandertal Models"!!!!

I'm with you Roger, lipo's are voodoo magic and should be banned completely, just like fireworks and pixies. They contain non earth-like materials that are way too complex for humans to understand and besides they are the wrong shape, I mean what's up with these square edged flat batteries? They just look weird. :confused: And a linear power curve!? That's simply ridiculous. :yawn:

Couple that with the absolute stupidity of staying cool while charging, it just doesn't compute. There are so many issues to consider, weird power delivery, reduced weight, being able to charge them and re-use them many times in a day and all that. It will change this sport forever and things will get totally out of control freaky. What's next? Batteries that don't need charging in cars that don't break? What will we do in between races? Will we actually have to talk to the people next to us and be all friendly like :eh?:



:thumbsup: lipo's rule dude, get with the program.

I'm not LiPo bashing not at all, just throwing an idea out there that's all!!!

In gerneral response ......

The power delivery thing first .... I want less not more ..... that's what I meant, personal choice though.


The weight issue is really aimed at those that are on tight budgets and planned on reusing there 08 cells in 09. A new charger and a pack or 2 of LiPos might be more than the budget can stretch to!
If they feel that they are at a big disadvantage before they even start they may not go to the race meetings in the first palce. The last thing we can afford to do as a sport is turn people off. Afterall the entry fee of these people is at least as important to the club holding the meeting as that of a world champ ... in fact these are the sort of people who probably race at that club every week and thus might be considered more imprtant than a roaming superstar!!

BigRed ...... garlic bread might be a meal feature but the future ... I think not ;)



(I know Super_Dan will be along in a while ..... did I mention starting a debate??? lol)

If BigRed is right and garlic bread becomes the norm do you really want close contact with your fellow racers????? :woot:


Why did I know people would see this as LiPo bashing ..... go back to my original post and find the bit where I say LiPos themselves are a bad thing ..... it's not there.

I have nothing against people running Lipo .. nothing at all. :p


Discussion is a good thing people ........

cheesy garlic bread for sure :wub

I dont necessarily agree with the budget side of things. You can buy a trackpower saddle pack I believe for £45 new and you could run all day on the 1 pack. You would struggle to buy 2 budget packs of nimhs for that, especially assembled with bars connectors etc

Personally, I think lipo's are BETTER for us normal folk and level the playing field. I don't mind being beaten by anyone who drives better than me (and that's a lot of people), what I do hate is being beaten by people with access to superior equipment. Anyone who races, and that includes Friday night drivers on a budget or superstars, knows that you have to buy batteries/motors etc. With lipo's you can get away with a couple easy and the price tag is no worse than a decent pack of NIMH. Coupled with that to keep the NIMH from going off you have to have a superduper equalizer/cell nurser and never ever breathe on the things. ........ Put the biggest capacity lipo you can in your car and you'll never get anywhere near to dumping so the lipo will stay in top condition. Get rid of all the expensive charging/discharging/looking after stuff and spend the money on a couple of packs of lipo's ......... as Lion-O said (almost), it's the future :thumbsup:

And you couldnt keep recharging the 2 packs of nimhs allday ;)

what he says!!

where is the poll choice " if they over the min weight its ok to run either"


or rog why not take a cell out of all your packs and run 5 cell and make your car lighter, then add a faster motor?

During the summer i ran my B4 with lipos at 1405grams race ready, it had better handling for me small tweaks to my setup, REDUCED tire wear, saving pounds on said tire and the power delivery was controlled by my thumb and speedo.
If your just Quote 'I'm not LiPo bashing not at all, just throwing an idea out there that's all!!!' End Quote
your proberly to late to make a difference. i spent a total of £44 on lipos in the last year and used them up to 4 times in one day. and are just as good on the track as the day i first ran them, excluding some marks on the hard case.
AS for a fire hazard, there are lipo sacks for about a tenner or a kitchen fire blanket.

I can see that your p**s*d off cos you will only be running your kyosho cars, fare play to that i ran a lazer 07 and 08, served me well, but i suspect your displeasure is because the new FS Lazer is saddles and the current saddle packs are highly possible the wrong size, thus you having a dig, bash, winge, moan, etc etc about lipos.

Have you every seen or heard of a mobile phone set itself on fire, as they are Lithium???

double post

you could but 2 packs of nimhs would struggle to do a whole season.

rodger as for power delivery i find the lipo more consistent over a 5 min run than shop bought or even team nimhs which makes it easier for me to get my pace right round the track. i personally objected to lipo for the simple fact that u have to modify most cars to fit them, but having used them i honestly feel its worth the hassle of making them fit

Gents

You may or may not agree but there seems to have been a vogue to race 1/8th offroad over the last few years.
I think lipo and brushless will redress the balance back to electric classes just like it has in TC, i raced my B4 last sunday for first time in 3 or so years, and was so much fun again, no constant maintaince and a TP 3600 will do at least 2 heats without recharging, 25mins practise how can this not bring people back its now more accessable than it ever has been.
On the debate on weight i know with the TC the car was awerful without it due to balance issues so i imagine we will be the same.

Yes but would you trust rogers little jonny cooking 2 packs of cells at 7 amps allday :p

If you are that worried about getting yourself a super-light car run 5 cells and a 4.5 motor.

maybe you are forgetting that this is off-road and that sometimes a bit of weight in the car is a good thing, calms the car down, slows down its reactions and helps you get an error free run

Alot of valid points raised, especially the garlic bread one.

Personally I love LiPo's, Ive never had or seen any problems with them and in MY opinion most of the horro stories you hear are 'a mates mates mothers son-in-laws LiPo went bang' and nothing closer to home.

There are rumours that I have heard, and I in no way associate myself with these rumours!, that the TC section have found people over charging and going onto the grid at 8.7V.....people charging on NiMh settings.....or so the rumour goes o.O
No doubt there are ways to police the SAFE use of LiPo's and no doubt PW with all his experience as Chairman and EB blokey will be looking into every possible angle.

I think LiPo is the future. I saw a video from one of your 'up North' indoor meetings afew days ago where an IB blew up indoors during the 2WD final, yet ive never seen a race video where someone gets their face blown off by a LiPo at a meeting.

Yes, we've all see the videos of people deliberatly over charging LiPos to make them go bang for the fear factor...but under normal sensible use? Nada.

Also, the fact that the LiPo does not drop off at all under load is just amazing! To drive LiPo after years of NiMh's is just a different world. No more banging it out of a corner and finding that its dropped down and bogged :D

I almost don't dare post this as it all gets sooo tedious, but here goes anyway..

Regarding safety - I personally saw some NiMh explode. Twas very very nasty indeed.

Prediction: NiMh won't even be an option in 12 months time.

As far as I'm concerned as long as cars are above the minimum weight limit I'm not fussed how heavy other peoples cars are.



You're called Smart Alec, for a reason aren't you. I'm completely with you, I bet in a couple of years ago we'll all wonder why we used nmih.

I bet you NiMh's stay around in certain classes for a while yet.

Its allll about the money..... :/

i think you'll find that roger runs a 4.5 in 4wd any way and cant see the problem,am i right roger??

you can buy lipos as cheap as nimh.

I personally see it going the same way as brushless

On my return to racing, I was running brushed but having seen the light, moved to brushless pretty quickly and havent looked back

Having said that, I will be running nimh next season as thats what I have relatively recently bought. LIPO all the way once they need replacing though :thumbsup:

I dont think you understood my point the way I intended it Matty lol

Matched NiMh's x lots of packs per season = lots of profit...*etc*cough*etc*

Not if they don't keep equalising them, keeping a storage charge in them when not in use and only charging them when they're cold they won't:woot:

Seriously though for a mo. I've just gotten my head round them new fangled NiMh things (which are still far more temperamental than the good ole 1400SCRs) but having run LiPo at 3 club meetings in the past week alone - I've gotta say that they make it easier to go racing because it drastically cuts down my pre-race prep time and my boss never liked me charging my IBs on my desk at work:thumbsup:

we ran one pack at bury indoors last week, ran the same one pack all day in 2wd with a 6.5 lrp sintered in a x6, was ace took around 1100mah top up the pack for the next round and never got them warm all day,the 6,5 was a little to quick to be honest a 7.5 would have been a little easier to drive,and as far as safety issues super glue is twice as dangerous, just ask the guy that got it in his eye, when he spun the back wheels up on his car,oops we even did two runs without topping up.

A little distraction from the topic but surely if when Lipos become the standard the 1/10th side of the hobby wins the drivers back from 1/8th side and you get to do 10min finals... Surely thats worth it.

Im with spud - I hadnt raced electric for years and come last sunday at Bury with 1 pack of 4000mah Lipos and a brsuhless it was just soooo easy. No skiming, no messing, no re peaking cells...

So when do we get to race 8 or 10 minute heats? Would it work? I guess it limits the number of rounds you'd get and/or number of people racing. Having said that, running a meeting with 10 minute heats would not be twice as long as a meeting running 5 minute heats.

10min finals rather than heats. I fully agree longer heats would cause problems in terms of planning a meeting.
RallyX generally is 5min heats with 10, 20, 30min or longer finals, increasing in order D Final - C - B - A being the longest..

10 min finals make sense. I like it.

Couldn't be more wrong mate ..... running a Novak 6.5L ..... seriously considering an 8.5 or maybe even a 15x3 brushed for the 2wd on NiMh cells!!!

I have a used once 4.5R (in a TC) if anybody wants it .... lol


What I am most interested in is the fact that most people have instantly goen on the defensive with the assumption that I am trying to say the LiPo revolution is a bad thing ..... I've not said anything of the sort!!!

I just like to get people thinking and talking that is all.

All I have asked is what do people think about reducing the weight benefit of the LiPo runners to even out the playing field a little whilst NiMh cells are still in peoples race kit.

My own 4wd is a stick pack chassis and to be honest would be nearly perfectly balanced side to side and front and back with a 3200 LiPo in place so I'd rather not add weight (170g side to side inbalance with E4500s).
I have absolutely no intention of going to the saddle pack FS even in NiMh format.

As Mr Doughty has pointed out a little bit of mass around the middle can be a very good thing when getting down and dirty in the rough :p (Why I've had nice steak for dinner not a salad). I once spent loads of time and money trying to get a Losi XX-CR down to the weight limit only to find it made it much worse to drive .... I was young and foolish (now old and foolish ;) )


I am finding people's responses to this thread very interesting!!!