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Old 02-14-2011, 08:06 PM   #31
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i like that one.
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Old 02-14-2011, 08:17 PM   #32
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Here's a simplistic equation to calculate chassis frequency:

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Old 02-14-2011, 08:21 PM   #33
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Here's a simplistic equation to calculate chassis frequency:

I'm glad I never learned that in Physics (something useful)...I hate High School
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Old 02-14-2011, 08:23 PM   #34
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The main difference in how a heavy truggy will jump vs. a lighter one is that the heavier one will take more fuel to do the same thing and need a bit more speed to go the same didtance. Like always, it's a trade off of sorts. The lighter truggy will more than likely jump easier and further, but may not feel as planted in the rough. The heavier one will feel more planted in the rough, but may not jump exactly the same.

Many former MX guys seem to pick up the 1/8th class pretty easy. The physics being so close to one another makes it that much easier to pick up. Getting used to not actually being on or in the car or truck, probably takes a little more effort to feel comfortable.
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Old 02-14-2011, 08:42 PM   #35
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The main difference in how a heavy truggy will jump vs. a lighter one is that the heavier one will take more fuel to do the same thing and need a bit more speed to go the same didtance. Like always, it's a trade off of sorts. The lighter truggy will more than likely jump easier and further, but may not feel as planted in the rough. The heavier one will feel more planted in the rough, but may not jump exactly the same.

Many former MX guys seem to pick up the 1/8th class pretty easy. The physics being so close to one another makes it that much easier to pick up. Getting used to not actually being on or in the car or truck, probably takes a little more effort to feel comfortable.



well thats one reason why i wanted a heavyer truggy anyways because it says more plated on the rough i can always lighten it up anyways if i want to.

yea i notice on my 1.0 t i did jump pretty far its light for a truggy.
so a heavyer one when jumping will nose dive more down nose up more ?

or is that all about where the weight is in the rear or the front ?
i know most truggys now have the engine mounted foward and tank also.

so a heavyer truggy in onces will be harder to jump with ?
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Old 02-14-2011, 11:48 PM   #36
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I'm glad I never learned that in Physics (something useful)...I hate High School
Don't worry about it, you are definitely not in the minority...
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Old 02-14-2011, 11:57 PM   #37
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well thats one reason why i wanted a heavyer truggy anyways because it says more plated on the rough i can always lighten it up anyways if i want to.

yea i notice on my 1.0 t i did jump pretty far its light for a truggy.
so a heavyer one when jumping will nose dive more down nose up more ?

or is that all about where the weight is in the rear or the front ?
i know most truggys now have the engine mounted foward and tank also.

so a heavyer truggy in onces will be harder to jump with ?
The reason why a heavy chassis can feel more planted is because the chassis frequency does not interfere (too high or too low of natural frequency) with the damping frequency of the suspension.

Nose up or down is all depend on the front/rear weight distribution and your throttle control. Jump distant/height is related to weight, that's why elephant don't jump...
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Old 02-15-2011, 03:12 AM   #38
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TC,

It's pretty much what ganymede said.

Two truggies that are only ounces apart, the differences between the two probably wouldn't be much. Two truggies that are a pound or so apart would be a little more of a difference. The issue is that in order to find the difference between the two, you'd have to drive both. One after the other. There's so many variables to consider there's not one simple answer.

As for weight placement on the chassis, that's a Mfg.'s design thing. There are many designs to look at these days on different Truggies, with each Mfg. claiming that "their" design is the best. Like I said before, it's a trade off. Finding the right balance in a design is why the designers get paid the big bucks. Sometimes it's perfect and sometimes not.
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Old 02-15-2011, 07:51 AM   #39
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Originally Posted by CJ Weaver View Post
I'm glad I never learned that in Physics (something useful)...I hate High School
I did.

Not sure what resonant frequency has to do with the original question (mass and relation to inertia and jump stability), but I think that the answer to the question lies more in the design of the suspension-related geometry, spring rates, shock pistons, fluids (both diff and shock), weight of the wheels/tires (unsprung weight and gyroscopal force), and aerodynamics (body and rear wing design/angle).

The question was in relation to how weight affects jumping. Weight has a bit to do with it, but also you need to take into account The following:
-how much the suspension loads up at the base of a jump (all you other MXers know about this!)
-speed: more speed typically means higher/longer jump
-curve and angle of the jump.
-Load/Rebound rate: consider this launch control.
-Wheel/tire weight: heavier tires will provide less "spring," due to the increased mass required to leave the ground. However, they will also provide you better pitch control (up/down angle, using throttle/brake) and yaw/roll (spinning wheels produces a gyroscopic effect, changing the axis' angle results in force on the mounted object).
-Tire BALANCE: Gyroscopic precession (wobble) directly effects stability in the air, particularly with truggies' heavier (relative to buggy) wheel/tire/foams.

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Old 02-15-2011, 08:05 AM   #40
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There will be a quiz at the end of the hour.
Damn, i hate quizzes.
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Old 02-15-2011, 08:40 AM   #41
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I did.

Not sure what resonant frequency has to do with the original question (mass and relation to inertia and jump stability), but I think that the answer to the question lies more in the design of the suspension-related geometry, spring rates, shock pistons, fluids (both diff and shock), weight of the wheels/tires (unsprung weight and gyroscopal force), and aerodynamics (body and rear wing design/angle).

The question was in relation to how weight affects jumping. Weight has a bit to do with it, but also you need to take into account The following:
-how much the suspension loads up at the base of a jump (all you other MXers know about this!)
-speed: more speed typically means higher/longer jump
-curve and angle of the jump.
-Load/Rebound rate: consider this launch control.
-Wheel/tire weight: heavier tires will provide less "spring," due to the increased mass required to leave the ground. However, they will also provide you better pitch control (up/down angle, using throttle/brake) and yaw/roll (spinning wheels produces a gyroscopic effect, changing the axis' angle results in force on the mounted object).
-Tire BALANCE: Gyroscopic precession (wobble) directly effects stability in the air, particularly with truggies' heavier (relative to buggy) wheel/tire/foams.

There will be a quiz at the end of the hour.
On handling, the chassis's mass affects the chassis frequency and that in turns affects the damping frequency of the suspension, if everything is tuned properly then the ride will be planted.

All things being equal, a lighter car will sure jump further and handle better if the suspension is tuned to the chassis.
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Old 02-15-2011, 09:09 AM   #42
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ok so if a heavyer truggy in onces is tuned to the chassis it whould be the same as a lighter truggy in onces ?
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Old 02-15-2011, 09:13 AM   #43
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(I think you meant oUnces)
No, because you're still carrying around more mass. Think a cadillac with a sport suspension versus a corvette.
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Old 02-15-2011, 09:19 AM   #44
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(I think you meant oUnces)
No, because you're still carrying around more mass. Think a cadillac with a sport suspension versus a corvette.


yea, i meant ounces i have aka premount truggy tires so that takes a good bit of weight off anyways alright im getting the rc8t ce thats final in march \

rc8t ce specs : 9.3 pounds without electrics and engine etc.

eight-t 2.0 : 8.5 pounds i believe without the electrics and fuel engine etc.


i dont think i will notice a diffrence im just a club racer.
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Old 02-15-2011, 09:29 AM   #45
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Maybe we should change the title of this thread to "Should tc5 man buy a new truggy?"
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