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Old 09-30-2007, 07:34 PM   #1906
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It was from an 18T and he also had a 360 sized mamba brushless in it also. He put it in his CK 3.2 and it just wouldnt turn and had no forward bite. I will give it a shot again with a 1 cell but the voltage is just not there nor is the weight.
OHHH

So it wasnt a proper sized pack..... I guess there was no bite lol, those packs weigh nothing....

I was thinking something bigger.
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Old 09-30-2007, 08:15 PM   #1907
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With the lighter battery and/or motor if someone were to try 380 sized much softer tires would be needed to compensate for the loss in weight. At least whites I would think. If enough research were done into it I think 380/lipo would be great for 1/12th once brushless is mainstream. Just think with the really small pod you could make how much more options become available in designing bodies. If we could just get the upper arms lower on the front suspension you could have some really nice and very scale looking bodies.
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Old 09-30-2007, 08:26 PM   #1908
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Note that this is not a "Tweak screw". There is no such thing on the DB12R because it will not tweak...trust me...we have done some evil testing on this point.
So then how does one adjust the chassis to compensate for uneven tire wear?
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Old 09-30-2007, 08:31 PM   #1909
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So then how does one adjust the chassis to compensate for uneven tire wear?
Rotate the tires and adjust your camber for even tire wear in the front.
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Old 09-30-2007, 08:37 PM   #1910
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Going to race 12th scale and TC at the stockton indoor track for winter

They have been lipo legal, but my out door track is only 10 mins away from me, and lipos are now legal... Stockton is about 1 and a half hours away
lipo won't be legal at stockton for 12th. unless of course, Mr. Race Director changed his mind and didn't tell me
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Old 09-30-2007, 08:58 PM   #1911
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5000mAh 1cells LiPo with 5.5 motor, wonder how much run time it can last, 15mins?
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Old 09-30-2007, 09:00 PM   #1912
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lipo won't be legal at stockton for 12th. unless of course, Mr. Race Director changed his mind and didn't tell me
Ohh, I thought lipos in everything were legal as long as they have a hard case.....

I guess your racing there also?
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Old 10-01-2007, 03:23 AM   #1913
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So then how does one adjust the chassis to compensate for uneven tire wear?
Carlos is correct. No matter which car you run, you do not want to run tires that are uneven left to right. You always want to rotate the tires each run. Unfortunately uneven tire wear is inevitable unless the track has no straight away. The sweeper or hard turn at the end of the straight is the tire killer. Keep rotating tires after each run and you will not have any issues.
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Old 10-01-2007, 03:26 AM   #1914
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With the lighter battery and/or motor if someone were to try 380 sized much softer tires would be needed to compensate for the loss in weight. At least whites I would think. If enough research were done into it I think 380/lipo would be great for 1/12th once brushless is mainstream. Just think with the really small pod you could make how much more options become available in designing bodies. If we could just get the upper arms lower on the front suspension you could have some really nice and very scale looking bodies.
Yes, it would be cool but the 360 and lipo will require a whole new design of car. There is too much to change to make it work. Tires alone will not do it.
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Old 10-01-2007, 07:15 AM   #1915
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I really appreciate the BMI 1/12 scale site. It has alot of information that helps alot. Saturday at the race track I started 3 and finished 4. The car was great I had one bad corner and let the fourth place guy around me, and was not able to get back to him in time to pass him.

Still like the car.

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Old 10-01-2007, 07:22 AM   #1916
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Default proper thrust bearing

Is the proper Slapmaster thrust bearing for the DB12R part #101 or #109?

I'm going to order one of them, just want to be sure I get the correct one.

Thanks!
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Old 10-01-2007, 08:29 AM   #1917
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Jason,
I see a person asked the rather rude question "do you pay for your own cars". As a manufacturer you know you pay the hightest price for your personal cars, mega R&D costs. The car you are running is the prototype and it has the highest cost of all, about 10X's. As a developer of performance products myself I do the same thing, run the prototypes. The customers get the final products that are refined. As a manufacturer it is your right to use a production kit if you need a second car. Is that no different than you sending a kit to one of your team drivers?

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Old 10-01-2007, 08:50 AM   #1918
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Kind of a weird question J

But do you pay for your own cars?

When was the last time you had a free meal???? What did it really cost????

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Old 10-01-2007, 09:01 AM   #1919
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So then how does one adjust the chassis to compensate for uneven tire wear?
I set mine by eye sight

place the car on a smooth flat surface ready to run but no bodyshell.

place something you know to be a true 90 degree angle, in my case a small set square.

adjust the camber turnbuckle until your happy that the gap between the rim and the straight edge is the minimum you can get after spinning the wheel a few times.

after a few runs you may see the foam showing signs of wear then adjust to reduce the wear. I'm only talking of say 1/16th of a turn @ a time either way
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Old 10-01-2007, 10:04 AM   #1920
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adjust the camber turnbuckle until your happy that the gap between the rim and the straight edge is the minimum you can get after spinning the wheel a few times.
Adjusting front camber to eliminate coneing is a pretty basic part of setting up any pan car. This is not what most would call uneven tire wear -- the term used is coneing. The target is with a small amount of negative camber -- as the tires wear, the amount of negative camber required is reduced.

Uneven tire wear happens on most race tracks (Suzuka in Japan is an exception) because there's more turns one way than the other way. In general, road course races are run in a clockwise direction, while oval races are run counterclockwise. It's pretty basic coming to the realization that on oval cars, the tires on the right hand side of the car wear quicker than the tires on the left. Similarly, on road course cars, the left side tires generally wear quicker than the tires on the right.

Simply rotating the tires from one side to the other every race will tend to even out the tire wear, but nonetheless, they will not wear entirely evenly. Also, the placement of gear on the chassis will affect the cross-weight, which is what the tweak adjustment controls.

One of the important lessons I've learned in my years of racing 1/12 scale cars is to always check the tweak after adjusting the ride height. Adjusting the shims in the front, no matter what shims you use, will cause a slight change in the cross-weight of the car. Swapping out rear bearing excentrics will also cause a slight change, since no two parts are truely identical. If you're used to a car that handles well, throwing your car on the track after adjusting the ride height and not tweaking the tweak is sure cause for a 3rd place finish at best.

Pardon me for being skeptical, but the above is just my experience running a few T-bar cars (Associated 12L and Revolver), as well as the CRC Carpet Knife. True, I didn't throw my 1st 1/12 scale car (an Associated 12i) on the board much, but since it didn't have provisions for adjusting tweak, there wasn't much point. It's also true that a Carpet Knife could run circles around a 12i. Although I've never run a Corally, one advantage of that chassis is the lack of tweak adjustment.

If the BMI truely doesn't benefit from a tweak adjustment, that's pretty cool. However, unless the chassis is laid out in a way different than how I think it's laid out (I've yet to see one in person), it seems to me that this may come back to haunt the design. As mentioned previously, this adjustment is critical in my experience for fine tuning the adjustment of the chassis after changing ride height. Not only that, but on some track lay-outs, it can be advantageous to run a little wedge (the term used when you intentionally run a little bit of tweak). If there's no provision for adjustment, than this go-fast tuning trick just doesn't apply.

Besides, rotating tires every race is a pretty big pain in the butt when you're running the race day as well. Not only that, but this technique definately will NOT work if you're runnnig two classes with the same chassis -- you'd need one set per class, and it would be a major inconvenience (not that I do that).
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