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Old 01-30-2014, 04:29 PM   #13531
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Originally Posted by Bracket View Post
MM3 will handle a little more like a RM3 because of the weight transfer under acceleration.

It honestly comes down to your driving style. Mid-motor rewards smooth driving with faster corner speed, whereas rear-motor rewards twitchier driving with better on-power traction.
The problem I have with MM4 is the weight shift. It gets worse with increasing power. A 4 gear setup can pick the front wheels up pretty easily. The certainly makes it a bit more difficult to steer when under power coming out of a corner. With an MM4 setup, you really need to coast through a corner or go very gently on the throttle until you are most of the way through it. I do all of my braking for a corner before I even turn. By the time I start turning, I'm back on the power again. This isn't point and shoot driving either. MM3 allows me to do that easier.

When you let off the gas and hit the brakes, MM4 will transfer weight forwards more abruptly in that instant you hit the brakes. This unloads the rear tires faster which decreases your braking power and hurts a little bit of your rear grip. Hit the brakes hard after you've turned the wheel on an MM4. The rear end will come out faster than it will on an RM car.

Once you understand that the important thing for making traction is weight on the wheels, you'll learn how to move the weight around so you can make the car handle like you need it to. You need a certain amount of weight on your tires. Too much is just as bad as too little. A rear motor car as a consequence of it's layout, has more weight on the drive wheels than a mid motor car does. It is this sole fact that allows RM cars to have more rear grip. About 67-69% or so of the total weight is on the rear wheels on an RM car. With the motor hanging behind the rear axle centerline, it acts like even more due to leverage. An MM car has about 62-63% or so on the rear wheels with the random car hitting 65%. This few percent difference may not seem like much but it makes a world of a difference in grip.

That added weight in RM is typically so much that we try to counteract it somewhat. The opposite rotation of the motor helps with artificial weight shift and running antisquat also resists artificial weight shift as well. With MM however, in MM4, this weight shift from the motor rotation is being relied upon since there isn't enough static weight back there. This gives good straight line forward grip for acceleration but at the expense of shifting weight off of the front tires which are used for steering. On power acceleration is more difficult as a result. People still like to run antisquat to counter this. I prefer to run MM3. You don't get the artificial weight shift as in MM4 mode so on power steering is maintained at a higher level. By having the proper amount of rear weight, but inside the wheelbase of course, there is now enough forward traction. I also run no antisquat which helps. Under braking there isn't as dramatic of a rear end unloading so braking and corner entry are improved.

Yes you can tune out the on power understeer on an MM4 setup. You'll sacrifice off power turn in though. Yes you can tune out off power turn in problems in MM4 but you'll sacrifice on power corner exit. MM4 is all about chasing your tail because it isn't addressing the fundamental problem of static weight. It relies on aritifical weight transfer to compensate.

I know the guides state which setup to use and when but the one thing they fail to mention is static weight. That is the missing piece of the puzzle and the least understood. There's a good reason why the new B5M has a full saddle (square) pack run all the way back against the motor while the B5 has the same pack moved forwards in the center. Yes the B5M is run as MM4 but they certainly seem to be zoning in on the fundamental issue.
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Old 01-30-2014, 05:09 PM   #13532
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As english is not my language there are some things that i cant understand... Anyway, im trying this setup and ser what it feels like... Im not racing so it justo to try and ser what happens...
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Old 01-30-2014, 05:30 PM   #13533
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Fred, have you posted any pics of your chassis? I know you said you've made your own. I'd be interested to see what you came up with.

From the looks of the v2 pics posted earlier, looks like durango didn't change their layout to do saddles. Pretty disappointing.
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Old 01-30-2014, 06:09 PM   #13534
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Originally Posted by fredswain View Post
The problem I have with MM4 is the weight shift. It gets worse with increasing power. A 4 gear setup can pick the front wheels up pretty easily. The certainly makes it a bit more difficult to steer when under power coming out of a corner. With an MM4 setup, you really need to coast through a corner or go very gently on the throttle until you are most of the way through it. I do all of my braking for a corner before I even turn. By the time I start turning, I'm back on the power again. This isn't point and shoot driving either. MM3 allows me to do that easier.

When you let off the gas and hit the brakes, MM4 will transfer weight forwards more abruptly in that instant you hit the brakes. This unloads the rear tires faster which decreases your braking power and hurts a little bit of your rear grip. Hit the brakes hard after you've turned the wheel on an MM4. The rear end will come out faster than it will on an RM car.

Once you understand that the important thing for making traction is weight on the wheels, you'll learn how to move the weight around so you can make the car handle like you need it to. You need a certain amount of weight on your tires. Too much is just as bad as too little. A rear motor car as a consequence of it's layout, has more weight on the drive wheels than a mid motor car does. It is this sole fact that allows RM cars to have more rear grip. About 67-69% or so of the total weight is on the rear wheels on an RM car. With the motor hanging behind the rear axle centerline, it acts like even more due to leverage. An MM car has about 62-63% or so on the rear wheels with the random car hitting 65%. This few percent difference may not seem like much but it makes a world of a difference in grip.

That added weight in RM is typically so much that we try to counteract it somewhat. The opposite rotation of the motor helps with artificial weight shift and running antisquat also resists artificial weight shift as well. With MM however, in MM4, this weight shift from the motor rotation is being relied upon since there isn't enough static weight back there. This gives good straight line forward grip for acceleration but at the expense of shifting weight off of the front tires which are used for steering. On power acceleration is more difficult as a result. People still like to run antisquat to counter this. I prefer to run MM3. You don't get the artificial weight shift as in MM4 mode so on power steering is maintained at a higher level. By having the proper amount of rear weight, but inside the wheelbase of course, there is now enough forward traction. I also run no antisquat which helps. Under braking there isn't as dramatic of a rear end unloading so braking and corner entry are improved.

Yes you can tune out the on power understeer on an MM4 setup. You'll sacrifice off power turn in though. Yes you can tune out off power turn in problems in MM4 but you'll sacrifice on power corner exit. MM4 is all about chasing your tail because it isn't addressing the fundamental problem of static weight. It relies on aritifical weight transfer to compensate.

I know the guides state which setup to use and when but the one thing they fail to mention is static weight. That is the missing piece of the puzzle and the least understood. There's a good reason why the new B5M has a full saddle (square) pack run all the way back against the motor while the B5 has the same pack moved forwards in the center. Yes the B5M is run as MM4 but they certainly seem to be zoning in on the fundamental issue.
Curious about one thing... I'm installing a new motor on the car, i would like to see your cable configuration, or your electric configuration.. I'm tempted to change the ESC to the right and the receiver to the left but would like to see how have you done
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Old 01-30-2014, 06:50 PM   #13535
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Originally Posted by lovethebuggy View Post
Curious about one thing... I'm installing a new motor on the car, i would like to see your cable configuration, or your electric configuration.. I'm tempted to change the ESC to the right and the receiver to the left but would like to see how have you done

Here is a pic of my wiring job not great but gets the job done.
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Old 01-31-2014, 02:19 AM   #13536
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Here is a pic of my wiring job not great but gets the job done.
Thanks!! I was asking for the mid motor 3 gear configuration but i can see it just to be the opposite of your configuration! I like those direct connections to the battery, are these really safe to use?
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Old 01-31-2014, 02:33 AM   #13537
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Originally Posted by lovethebuggy View Post
Thanks!! I was asking for the mid motor 3 gear configuration but i can see it just to be the opposite of your configuration! I like those direct connections to the battery, are these really safe to use?
It's perfectly safe, just need to pay attention when plugging your leads in
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Old 01-31-2014, 02:39 AM   #13538
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Originally Posted by flame56mx View Post
I ran mine all the way back, but that was in blinky. Mm4 will create a ton of weight transfer, especially with a mod motor, so shock oils/pistons will really come into play. I went 5wt lighter in the rear, and the lost on power steering almost altogether.
are you guys running shorty in mod class? I"m running an SMC shorty and 6.5 with my Speed Passion ESC and I seem to get great run times and my motor stays very cool. Usually less than 120F when I come off the track.

I"ve just spent the day at OCRC running on the Reedy race layout. It's pretty badass. Super fast, big jumps and you can tell they spent quite a bit of time making sure each lip is perfect. My 210 setup with IONS MC front and rear seems almost perfect. I just have a bit too much wheelspin on exit if I'm not too careful on the throttle. I think once the tires are broken in it will be close to perfect. I will post my full setup sheet soon. MM4, Shorty, 30wt, 1.2x6 all around, Front Springs Avid Purple, Rear Springs Avid Red. Proline Ions MC with AKA Red Foams.

For those not super familiar with OCRC check out the latest news on the Reedy race. The track is pretty hard packed clay (red clay?) and has a nice blue groove to it. It's very large for an indoor track and has very wide lanes. It has two large jump sections, a nice switch back, and a really nice long straight into a sweeper with 3 step down elevation changes. Very challenging and awesomely fun.

Forgive the long diatribe here...
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Old 01-31-2014, 02:45 AM   #13539
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Smile Shorty Pack layout

Here's a pic of my new shorty layout. It's very close to perfect side to side weight as my receiver and capacitor are very similar if weight. Shorty pack lets me get my ESC in front.

I hope they allow for SQ/Saddle setup like the others on the V2.
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Durango DEX210 Thread-img_2504.jpg   Durango DEX210 Thread-img_2503.jpg   Durango DEX210 Thread-img_2502.jpg  
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Old 01-31-2014, 03:03 AM   #13540
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Originally Posted by 13Maschine View Post
Here's a pic of my new shorty layout. It's very close to perfect side to side weight as my receiver and capacitor are very similar if weight. Shorty pack lets me get my ESC in front.

I hope they allow for SQ/Saddle setup like the others on the V2.
It's the same layout as the current buggy, can see some pics of it here http://www.area52.cc/news/4593-toyfa...m-durango.html
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Old 01-31-2014, 04:39 AM   #13541
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Looks like an alum. chassis but +8? Also looks like saddle packs down the middle with mid motor which is nice. Now I can swap packs between my 410 and 210 at least….

It's too bad they didn't consider the square packs. I know it's blasphemous but I'm kinda drooling over the B5M for this reason.
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Old 01-31-2014, 05:10 AM   #13542
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are you guys running shorty in mod class? I"m running an SMC shorty and 6.5 with my Speed Passion ESC and I seem to get great run times and my motor stays very cool. Usually less than 120F when I come off the track.

I"ve just spent the day at OCRC running on the Reedy race layout....
Yeah,I have never used anything but a shorty in 210, regardless of config, its just seems to work better for me. I have tried saddle on my V1 in mm4 before, and though they gave me better rear bite, there was a big transfer to off in off power steering (whoa?)

I'm jealous of this..
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Old 01-31-2014, 05:24 AM   #13543
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i guess i would be better making a new car than fixing this one...

Now the servo started to act strange... It stays to one side and no response from the radio, after moving the wheel like 14 times it actually moves but is always pushing to one side, it gets super hot and some smoke went from the side...

Does this mean i need a new servo

Is there any servo that not cost more than my motor :'(
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Old 01-31-2014, 05:39 AM   #13544
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i guess i would be better making a new car than fixing this one...

Now the servo started to act strange... It stays to one side and no response from the radio, after moving the wheel like 14 times it actually moves but is always pushing to one side, it gets super hot and some smoke went from the side...

Does this mean i need a new servo

Is there any servo that not cost more than my motor :'(
Yeah, sounds like yours is finished. There are some decent servos out there, and if you are not racing the car, you wont need the best or the fastest one. I am not sure how much you spent on your motor, but you can get a good servo for around $50..
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Old 01-31-2014, 05:46 AM   #13545
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Yeah, sounds like yours is finished. There are some decent servos out there, and if you are not racing the car, you wont need the best or the fastest one. I am not sure how much you spent on your motor, but you can get a good servo for around $50..
lol, i bought the speed passion competition v3.0 for 40 xD

What would be a good servo? Is impossible to fix that?
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