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Re: Mid motor car question

Posted: Wed Nov 25, 2009 6:23 pm
by scr8p
so, is this 4 gear trans an upgrade for them? because on their earlier cars i've seen, the endbell is clearly on the right side.

Re: Mid motor car question

Posted: Wed Nov 25, 2009 6:48 pm
by scr8p
pic from oople..........

this is supposed to be an x-6 squared. i guess that's the new one?
P4180064.jpg
as you can clearly see, the motor is installed from the right. being this way, i can fully understand the need for a 4 gear trans. but it wouldn't seem like the rotation of the motor in that configuration would be promoting more rear bite.

i'll understand it eventually...................

Re: Mid motor car question

Posted: Wed Nov 25, 2009 7:10 pm
by scr8p
alright, i think i got it now. it's supposed work under the...... every action has an opposite reaction.

being as though an armature spins counter-clockwise (looking at it from the pinion side), if you were to hold that, which way would the can spin? clockwise. so, they're using that clockwise force of the can to transfer weight to the rear, because it's bolted down (unlike the armature), that force is transfered into the chassis.

i think that's it anyway...........................

Re: Mid motor car question

Posted: Wed Nov 25, 2009 7:46 pm
by SoloGraphix
I have an x-6 squared, and you are exactly right. They changed to the 4 gear to utilize the rotation of the engine to properly transfer weight. I just got mine dialed pretty well and the last race I ran I won over 4WD buggies because they combined us.

Have you ever seen the Dynotech delta sprint car where they stood the motor up to help utilize the rotation of the motor to rotate the car in the turns?

Re: Mid motor car question

Posted: Thu Nov 26, 2009 12:19 am
by m_vice
scr8p wrote:
markt311 wrote:hold a motor in your hand with the endbell to the left like a conventional setup and hit the gas, it wants to rotate to the rear. Hold the motor with the endbell to right and do the same thing, it wants to take off towards the front.

That same force is either pushing the rear of the car down creating more rear traction, or (to the right) trying to lift the rear end. By adding the fourth gear and keeping the endbell facing the left you are using the motor as a mechanical advantage by pushing down the rear of the car under acceleration, creating more rear traction.
i know how a motor rotates. which is why i can't seem to wrap my head around why they (x-factory) would add a 4th gear to the trans in order to have the endbell on the right side of the car. especially if the whole goal in the design is to create more rear traction. :?
:?

if we are talking about motor rotation. The motor rotated the same way in my car as it on the new X-6... but the X-6 needs a extra gear because the motor is pointing to the other side.
NO?

sorry about this guys, but it is a confusing situation.
thanks for you working on clarification to this situation.

Re: Mid motor car question

Posted: Thu Nov 26, 2009 12:54 am
by SoloGraphix
OK, this is from the x-factory forum, and the best info I can find.

The semi-detailed explanation: for ever action there needs to be a reaction, right? Well, when the motor puts torque to the drivetrain, it 'pushes' against the chassis through its mounting screws - and the chassis has to provide that torque back. Where's the chassis torque against? The ground, and we call this action 'fore/aft weight transfer'. With three serial gears in the transmission, the motor spins opposite of the wheels. That means the chassis' torque against the motor is in the direction the tires spin, or front down, rear up: weight transfer to the front wheels. Adding the fourth gear changes that direction: to push against the motor's torque the car loads up the rear wheels, giving more rear bite on acceleration.

Re: Mid motor car question

Posted: Thu Nov 26, 2009 8:10 pm
by cmain
It is confusing all last season when I was running a 3 gear I tried to get the truck to squat but could not figure it out till I stumbled on the x-factory thread. It is a night and day difference it went from a unpredictable truck that could spin at any time to a traction machine :D

Re: Mid motor car question

Posted: Sat Nov 28, 2009 5:38 pm
by trx450racer174
This thread is very informative as i am building a mid motor truck.
After doing some research i stumbled across this pic on oople and it is a very good idea at adding a 4th gear to a 3 gear trans.
4TH GEAR PIC.jpg
4TH GEAR PIC.jpg (50.32 KiB) Viewed 1370 times
4TH GEAR PIC.jpg
4TH GEAR PIC.jpg (50.32 KiB) Viewed 1370 times

Re: Mid motor car question

Posted: Sat Nov 28, 2009 8:24 pm
by m_vice
trx450racer174 wrote:This thread is very informative as i am building a mid motor truck.
After doing some research i stumbled across this pic on oople and it is a very good idea at adding a 4th gear to a 3 gear trans.
4TH GEAR PIC.jpg
I have seen this photo, (thanks) and it is very logical to me to add the 4th gear to this set up if you have the motor plate to this side of a 3 gear tranny because of motor rotation.
But, if the motor plate is in the opposite side and you want the motor to rotate the same way as this setup you need to keep 3 gears.
I have a feeling that this 4th gear setup has to add something more than motor rotation to add traction.

Correct me if this is incorrect, please someone.

Re: Mid motor car question

Posted: Sun Nov 29, 2009 3:27 am
by Mr. ED
it confuses the hell out of me, but if it works someone should do this with a YZ10 type transmission ;)

should be easy to test: disconeect your gearbox from the wheels and hit the throttle: which way does the suspension act: lifting up or pushing down

Re: Mid motor car question

Posted: Mon Dec 07, 2009 2:27 am
by AscotConversion
I don't know how many of you ever ran a TC3, but the "torque steer" everybody talked about was a similar concept. The motor wanted to climb the spur gear, so the right rear tire could get light. A lot of people would add extra droop to the right rear tire to compensate. A brush motor also adds to this as the wire packed arm creates a lot of intertia.

Re: Mid motor car question

Posted: Sat Dec 12, 2009 8:00 pm
by JK Racing
Maybe this will help some....with a 3 gear trans, your spur rotates opposite as the rear tires, 4 gear it rotates the same. Your motor rotates "up" with a 3 gear, "down" with a 4 gear. Something like that...maybe I have it backwards, but I know the 4 gears helps push the rear end down during acceleration.

But lets see if my little graphic helps...

Re: Mid motor car question

Posted: Sat Jan 02, 2010 2:09 am
by Jacobey
SoloGraphix wrote: Have you ever seen the Dynotech delta sprint car where they stood the motor up to help utilize the rotation of the motor to rotate the car in the turns?
I always wondered why they stood the motor up on the Dynotech's, makes since now. Definately a different design and way of thinking :wink:

Re: Mid motor car question

Posted: Sat Jan 02, 2010 5:39 am
by Lowgear
The simplest answer I can give to the ones who are still having a tough time understanding this is they are using the motors gyroscopic effect.

Re: Mid motor car question

Posted: Mon Jan 04, 2010 11:14 am
by cyberded
Having race B4 and X6,im thinking that the dynotech car would be realy touchy to throtlle input.im not convinced of the design.
they do make super a-arm for rc10 thought... :mrgreen: :mrgreen: