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Old 01-17-2015, 03:55 PM   #15781
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I just finished listening to the RIP podcast with Kody Numedahl and he was asked about the new b5 three gear tranny. He said that they (AE) originally designed it thinking it would be good for stock because of the less rotating mass because of 1 less gear, but what they are finding out is that it does not transfer as much weight backwards on acceleration and also does not transfer as much weight forward on braking. Well that is interesting because we have known that for sometime with the durango platform, but I guess it is true now that AE says so.
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Old 01-17-2015, 04:05 PM   #15782
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You mean a guy that actually designs the cars is surprised at elementary physics and didn't realize this until they actually built and ran it? If that's true then it really calls into question the logic for the entire vehicle design. Incidentally it's the same suspension physics that the 210 copied.

Durango: Here's a free tip. Redesign the front end so that with the 25° nose kick, the front arms move at the exact same angular displacement as the rears per the same vertical amount of wheel travel. The arms won't be the same length front to rear like AE does. They don't understand this either. Durango will be the geometry to beat if you do this.
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Old 01-17-2015, 10:21 PM   #15783
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I'm not done listening to that podcast, but running the 3mm set up in the b5 was an after thought for mod, it was made specifically for stock and less rotating mass. Maybe I'm not smart enough yet, but what do you mean by angular displacement?
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Old 01-17-2015, 11:03 PM   #15784
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I'm not done listening to that podcast, but running the 3mm set up in the b5 was an after thought for mod, it was made specifically for stock and less rotating mass.
There has been lots of info on this thread as to why mm3 makes for a more planted chassis because it does not get affected by weight transfer like mm4 does. So the theory is, set your car up mm3 and put the weight were you want it to be and then because mm3 does not transfer as much weight under acceleration and braking the car will be easier to drive and will handle better. This all depends upon it being set up correctly first though. Then AE comes out with a mm3 and states it is for stock because it has less rotating mass. During the podcast Kody says that same thing but what they are discovering is what I just stated above. He says that wow it even makes a mod car better to drive because of the less weight transfer.

Just look back through this thread at Fred's posts and he has been saying the same thing. There are a bunch of guys running mm3 for that same reason. My point was that now since AE says that it must be true, if you know what I mean ...


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Maybe I'm not smart enough yet, but what do you mean by angular displacement?
Not to answer for Fred, but I think what he meant was he wants a chassis where the front is not kicked back like they are now. He wants the kickback to be the same on front as it is on the rear. Fred you can correct me if I am wrong about this.

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Old 01-17-2015, 11:13 PM   #15785
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Wow...had no idea my setup could be so night and day. With 14 buggies and 2 bump ups, I barely got in and started last in the A main after struggling like crazy with the setup. Didnt change anything between the B and A main yet somehow finished 3rd just by the track cooling down and getting tacky. Interesting day to say the least haha
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Old 01-18-2015, 12:59 AM   #15786
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why would you want less weight transfer?

weight transfer is good....isn't it?

weight transfer gets the job done of putting weight on the rear wheels during acceleration, and putting weight on the front when coasting/braking to assist cornering duties.
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Old 01-18-2015, 01:01 AM   #15787
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why would you want less weight transfer?

weight transfer is good....isn't it?

weight transfer gets the job done of putting weight on the rear wheels during acceleration, and putting weight on the front when coasting/braking to assist cornering duties.
You do want some but too much can upset your car...can't steer if doing wheelies, can brake if rear wheels are jacking.

If you set your car up correctly so the weight is at where it is needed then why do you need weight transfer?

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Old 01-18-2015, 02:08 PM   #15788
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hey guys, I am working on setting up my vehicle and I am looking through my spring sets but having trouble identifying 2 sets in particular.

1 set has the color towards the end of the spring like the durangos, but rolls it over to the "front of the spring by alot.

Any ideas on what brand this is? I can post pics, but the colors that make me thing not durango are that it has a white spring and I don't see that on my durango chart.

Also, anyway to tell what a durango spring is without the color present? got some worn ones but not sure how to tell what they are without some sort of spring dyno.
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Old 01-18-2015, 03:01 PM   #15789
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The less rotating mass thing is just moronic. Yes, technically one less idler gear has less rotating mass but it's a small diameter and that extra gear is only worth about 1% in efficiency change. Temperature has a greater effect than that. I used to design drive systems for oil drilling so I laugh at what some people believe vs what is.

In regards to the front kick, lets say we have arms with no kick, so level. If you move the wheels up and down, keys say 2" in total travel. If you lean that suspension back 25° but then move those arms the same amount, you will not have the same amount of total wheel travel. You'll have less. You'll need to physically move the arms over a wider total angle to obtain the same wheel travel vertically. By lengthening the arms to compensate, you can maintain the total amount of movement the arms make in regards to how many degrees they move in order to maintain the same wheel travel vertically. Obviously we get to a point where it's impossible. A 90° take would equal no vertical movement. The reason this is important is because the roll center changes would stay the same front to rear with suspension travel. They don't currently.
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Last edited by fredswain; 01-18-2015 at 06:39 PM.
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Old 01-18-2015, 06:40 PM   #15790
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Quote:
Originally Posted by fredswain View Post
The less rotating mass thing is just moronic. Yes, technically one less idler gear has less rotating mass but it's a small diameter and that extra gear is only worth about 1% in efficiency change. Temperature has a greater effect than that. I used to design drive systems for oil drilling so I laugh at what some people believe vs what is.
I always wandered that... One small idle gear, including the bearings, probably has less rotational inertia than the spur gear, diff, clutch, and shafts at least. Then a minuscule amount compared to the motors magnets and wheels/tires.

Why I think its more of a selling point than useful point.
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Old 01-18-2015, 09:33 PM   #15791
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Whats the offset of the new Exotek 12mm Rear hexs do you know ?
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Old 01-18-2015, 09:41 PM   #15792
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Quote:
Originally Posted by Cain View Post
hey guys, I am working on setting up my vehicle and I am looking through my spring sets but having trouble identifying 2 sets in particular.

1 set has the color towards the end of the spring like the durangos, but rolls it over to the "front of the spring by alot.

Any ideas on what brand this is? I can post pics, but the colors that make me thing not durango are that it has a white spring and I don't see that on my durango chart.

Also, anyway to tell what a durango spring is without the color present? got some worn ones but not sure how to tell what they are without some sort of spring dyno.
Might be Losi springs. The originals were marked at the ends
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Old 01-18-2015, 09:49 PM   #15793
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For the Trans….I actually prefer the stock components with the weight, even for 17.5. Sure it slows the acceleration, however, if you don't lock the slipper it doesn't matter since your losing efficiency to gain steady usable traction which is really what makes the car move. The car is way smoother and easier to drive too. BTW…B5RM for sale now. Just built my first DEX210(old short chassis with updated flat arms in front), running MM3 in 17.5 and the car has such good manners. Its way better than any MM B5 I have driven.
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Old 01-18-2015, 10:13 PM   #15794
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Im asking because with them hexes there is about 3 axle treads showing and it looks like it narrows the Rear witch more than the Front . With the B4.1 Proline Hexs its wider and more equal to the Front end im just going by the eye i haven't try them out yet though.

Noticed a difference and handling also . Seemed like less grip out of the turns and not as stable/understeer on the buggy.

Im using the Evo 12mm Rear rims for the Associated since im running Evo tires.
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Old 01-19-2015, 07:09 AM   #15795
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Quote:
Originally Posted by bambambennett View Post
Might be Losi springs. The originals were marked at the ends
got a link to a pic of these?

I'll post a pic of what I got too when I get a chance. Heck got some springs here I am not sure what they are, no colors to be seen on them.
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