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Old 07-21-2008, 12:02 PM   #1
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Default Lowering the weight of Touring Cars that use lipo

Hi
I have been in this sport for just of 9 years, and have seen our cars sit at the same weight all this time 1500 grams (except for 5 cell mod) , but since the introduction of Lipo cells which weigh in the region of 230 grams as apposed to 440 gram NMH's it seems its time for a weight reduction, as it seems that we are for ever having to find a way of bring the cars upto minimum weight, which seems to me a little crazy. The electrics on my car (Cyclone TC) down the left hand side weigh approximately 330 grams, I know the lipo is lighter, but is about weight distribution to balance your car left and right front to back. Take a look at the pics of my car in this thread post #21 http://www.rctech.net/forum/showthre...88#post4658288
As you can see ive got my Orion 3800 Lipo to the outside of the car, but if I didn't have the hassle of making a weight plate (150 grams) to fit in the car, I could have put the Lipo closer to the middle of the car and put lead down the middle of the car. There are so many Lipo's out there now, and manufactures of Lipo cells wont/cant bring them upto weight, maybe we have a separate class for racers that use lipo 'Lipo Class Racing' (LCR) I think a good starting point would be around 1400 grams. I just think its time for a weight review, Any thoughts on this one
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Old 07-21-2008, 12:13 PM   #2
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While I understand what you are saying, I would have to say that it's too early for this change. There are still many using NiMh packs and I think it would hurt race programs to segregate into LiPo and non LiPo by weight. I happen to run LiPo but see many guys still running NiMh at our local tracks.

I also believe that many of the current platforms are built around the weight of NiMh and with my TC5(r) I used the PPD Billet setup which got me where I needed to be for weight distribution. Perhaps when LiPo is the norm - they will start manufacturing the chassis to run lighter and I personally think that would be the time to review the current weight standard.

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Old 07-21-2008, 12:19 PM   #3
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2 issues with lowering the weight. First, everyone has to be running lipo for it to be fair. Second, the cars get a LOT faster. We were running HPI rules this weekend (no weight limit). I had my car down to 1410g and was racing someone at 1300g. His car was ballistic. At least as fast as a 13.5.
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Old 07-21-2008, 12:26 PM   #4
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Originally Posted by Catalyst View Post
While I understand what you are saying, I would have to say that it's too early for this change. There are still many using NiMh packs and I think it would hurt race programs to segregate into LiPo and non LiPo by weight. I happen to run LiPo but see many guys still running NiMh at our local tracks.

I also believe that many of the current platforms are built around the weight of NiMh and with my TC5(r) I used the PPD Billet setup which got me where I needed to be for weight distribution. Perhaps when LiPo is the norm - they will start manufacturing the chassis to run lighter and I personally think that would be the time to review the current weight standard.

That's my shiny two pennies and a ball of lint for good measure...
Hi Catalyst;4658572
While I get where your coming from, I still can't see where the problem lyes, as if I hadn't had to add 15o grams, to the car, I still could have easily balance my car as the lipo is a nice piece of kit, why do we have to smother it in lead, which I first did until I came up with what ive done to keep the car upto weight, which is a PITA
Cheers Malc
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Old 07-21-2008, 12:26 PM   #5
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I disagree, as long as Nimh remain a viable power source the weight requirement needs to remain the same to keep the competition on equal ground. Lipo has made great headway in the power performance department, and will soon usurp Nimh as the power source of choice. However, as long as Nimh is a viable power source on a national/international level, the weights should remain as they are.

I have seen many cars with the extra weight added to the chassis to properly balance and bring the weight to minimum. The cars that I have seen don't look ridiculous and actually perform quite well. I have also seen cars that people gave no consideration on how to weight, and they perform like crap with wheels.

The cars that we are running today were designed with the weight of the battery in a particular location. As soon as you remove that weight you will upset the balance of the car. When the cars are designed specifically for Lipo become available, perhaps Nimh will be even less of a factor, and IFMAR will have approved their use.

Besides, just what we need, another sub-division of the classes.

BTW, I can agree to disagree on this one. When the time comes, I believe that it is not now, I will readily agree that it is time. Lipos are great tech... I just think it is stupid to mess up the balance/performance of a $500 sedan.

For club racing I run the SMC 28c 4000mah. My car is decently balanced and weighted with just 2 sticks of lead. One along the outside edge and one along the top outside edge.
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Old 07-21-2008, 12:31 PM   #6
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Quote:
Originally Posted by or8ital View Post
2 issues with lowering the weight. First, everyone has to be running lipo for it to be fair. Second, the cars get a LOT faster. We were running HPI rules this weekend (no weight limit). I had my car down to 1410g and was racing someone at 1300g. His car was ballistic. At least as fast as a 13.5.
This is why I have suggested 'Lipo Class Racing' it would still be stringent with ruling, just down to 1400 grams, so we don't have the hassle of finding around 200 grams of lead every time we get another car when using lipos
Malc
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Old 07-21-2008, 01:00 PM   #7
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I run lipo and don't want the rules changed as long as NIMH is still being used... I won't even comment on the 5 cell rule since I don't run mod....
I'm just happy that LIPO is now accepted at most if not all events....
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Old 07-21-2008, 01:02 PM   #8
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Quote:
Originally Posted by TheCoolCanFanMan View Post
This is why I have suggested 'Lipo Class Racing' it would still be stringent with ruling, just down to 1400 grams, so we don't have the hassle of finding around 200 grams of lead every time we get another car when using lipos
Malc
Take a long time and really think about what you're suggesting. How much time would that add to the race day?

I've just recently come back to RC, but a common point seems to be classes are to diluted as is and having large enough number to run can be a problem.

You want to take a class and slit it into battery types? really bad idea.
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Old 07-21-2008, 01:41 PM   #9
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I agree,

Lower the weight limit or remove it completely.

Classes wil have to change. Technology and classes change all the time.
Unfortunately times are/have changed lets not allow obsolete rules restrict the performance of the cars.

Maybe we should notify grenpeace that we are sticking lead weights all over our models because we gave up the lead in the cells! not too mention the idea of extra energy used to carry the excess weight.

The racers will decide by demand the future designs and you may have already seen offroad cars already designed and suited to lipo.

Sorry to all you nimh/nicad lovers but you will need new batteris soon why not buy LIPO? they are not scary they are cheaper overall and kinder to the enviroment.

Lets use them to the full.
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Old 07-21-2008, 01:50 PM   #10
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I am all for lowering the weights to reflect changes in the batteries.

If the weight limit is set too low, NiMH will be abandoned as LiPO would be the only battery that didn't penalize a racer with excess weight.

The weights should be lowered between 50 and 100g to encourage the use of LiPO, but not discurage the use of NiMH. Once the market focus changes to LiPO chassis will follow just as they did for 5-cell NiMH.

The only future problem I see with lowering the weights is the same struggles 1:12 and 1:10 pan cars have. With a lower weight, any motor can just about push the car to mod speeds.

I am all for lower weights because parts last longer, things break less, and tire last more laps and motors, batteries, and speed contorllers cost less with less power needed. I am concerned that if class weight for sedans were dropped to 1300g (completly possible) that the sedans would be bullets and then the Sedan class would be looking for a less powerful motor for stock racing. Back to the same problem pan cars have. The motors are too powerful when used with LiPO.

The answer to high powered motors is not incresing the windings. Windings just slow the motor down with low RPM but the wattage still remains high. With high wound motors, Torque causes problems with gearing properly. The answer will be a smaller diameter motor, with similar RPM range that we use today.
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Old 07-21-2008, 02:02 PM   #11
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has there been anymore talk about saddle pack lipo touring cars? i read this a while back and i'd like to know before i purchase another car.
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Old 07-21-2008, 02:02 PM   #12
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For club level theres no way you'll find a regular amount of racers to form a championship for it.

National level, yes there will be enough entrants potentially to make a class, but why dilute the classes. Same with STCC, SLCC etc etc...

International level... This is where I could see it happening but with a twist- put them all in the same class.... Give the best of the best a choice and see what they can do with it.

Everyone would be wondering what the other is using LOL... tactical racing?

Some would argue they are different cells and demand a seperate class. But I don't see it happening in the near future. Especially in the UK.

Brushed and brushless together though... oops, different can o' worms
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Old 07-21-2008, 02:12 PM   #13
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Quote:
Originally Posted by brit_bulldog View Post
I agree,

Lower the weight limit or remove it completely.

Classes wil have to change. Technology and classes change all the time.
Unfortunately times are/have changed lets not allow obsolete rules restrict the performance of the cars.

Maybe we should notify grenpeace that we are sticking lead weights all over our models because we gave up the lead in the cells! not too mention the idea of extra energy used to carry the excess weight.

The racers will decide by demand the future designs and you may have already seen offroad cars already designed and suited to lipo.

Sorry to all you nimh/nicad lovers but you will need new batteris soon why not buy LIPO? they are not scary they are cheaper overall and kinder to the enviroment.

Lets use them to the full.
Nobody is forcing you to use lead, that is your choice of ballast. There are many other things you can use to add ballast to your car; depleted uranium, tungsten, stainless steel, compressed cow chips and llama dung are just a few examples.

Like I said, I use Lipo in sedan. I want to know that I am on equal footing with a driver racing Nimh. Why should I alienate someone that perhaps can't afford to run out an purchase all new equipment because some dilweed wants to force feed their feelings on his sorry poor ass? Selfish and inconsiderate jackasses are all over the place.
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Old 07-21-2008, 02:18 PM   #14
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Originally Posted by trailranger View Post
I am all for lowering the weights to reflect changes in the batteries.

If the weight limit is set too low, NiMH will be abandoned as LiPO would be the only battery that didn't penalize a racer with excess weight.

The weights should be lowered between 50 and 100g to encourage the use of LiPO, but not discurage the use of NiMH. Once the market focus changes to LiPO chassis will follow just as they did for 5-cell NiMH.
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Like I said, I use Lipo in sedan. I want to know that I am on equal footing with a driver racing Nimh. Why should I alienate someone that perhaps can't afford to run out an purchase all new equipment because some dilweed wants to force feed their feelings on his sorry poor ass? Selfish and inconsiderate jackasses are all over the place.
Agreed, the switch to LiPO shouldn't be forced. If the hobby wants to move onto LiPO just do as I posted. Reduce the class weights a little here and a little later and over time racers replace their aging batteries and chargers a step at a time rather than a maxxed out credit card.
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Old 07-21-2008, 02:20 PM   #15
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I agree that lowering the wait needs to be slow progression due to the fact that people still use Nimh. I also agree that creating an all lipo classe would just make class size smaller. Could you imagine Stock/17.5, Stock/17.5 Lipo, 13.5, 13.5 Lipo, Mod, Mod Lipo as the classes at a trophy race? That would kill club racing.
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