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Old 07-03-2005, 11:11 PM   #10186
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Originally Posted by Jon Kerr
By raising the rear roll center, that will usually give less rear grip. A good rule of thumb with the lower suspension mounts is lowering on either end will give that end more grip. Raising the rear to 1mm above the 2mm riser plate should have made the car pretty loose going in. I've only tried that a couple times and have always gone back to just the riser. I prefer to tune turn in with the front of the car and exit with the rear of the car. It seems to keep things a little more balanced that way. Of course there are exceptions to that depending on the circumstances.
Which is why he was so confused, , I race with Bender, he had no turn in, but the car was loose coming out, and he took out the spacers from the rear and had more steering straight away. I had the opposite when I tried it, I had no rear grip what so ever.

I on the other hand had my Mi2 going well atm, I have a 1mm spacer at the front (with no riser) and std at the back, and was thinking, I would like the rear a bit more locked in, would having 1mm (with no riser) in the rear and no spacers in the front give a more locked in feeling but keep the steering the same??

Also, the alloy pivot blocks, do they give 2.5* toe in or 2*? I run with the 1.5* setting in mod.

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Old 07-03-2005, 11:39 PM   #10187
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The alloy blocks give 2º rear toe. If you're running 1.5º now, I'd put the alloy ones on to go to 2º. That will give the rear more bite going in. That's one of the exceptions as far as tuning the rear for turn in. The problem Bender had with a push going in and loose coming off is common. If the car pushes going in you'll have a tendency to try and whip the car into the corner and that will break the back end loose coming out. By fixing the turn in, you now don't have to throw the car around so the rear is able to work properly. It's all about balance.
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Old 07-03-2005, 11:59 PM   #10188
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According to the Xray tuning guide raising the rear roll centre gives the rear end less grip through a corner BUT more grip when turning in to the corner.

And obviously the reverse is true, so a lower rear roll centre will give less rear grip turning into corners and more grip through and out of corners.

It was after reading that that I decided to try it and it was immediately obvious that it was the right change.

I know it's not an Xray but obviously their idea worked for me.
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Old 07-04-2005, 12:02 AM   #10189
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Quote:
Originally Posted by Jon Kerr
Did you say you've lowered the rear roll center too by removing the riser? If so you'll want to put that back in. Having that too low may be causing the rear to have too much grip and not flow into and through the corners. Also one thing we've been doing on the front to gain some turn in is taking the carpet tower and notching the top middle camber link up about 2mm.
ok... i will put back the riser in the rear then, leaving the front without it. i'm sold out with the carpet tower already and will just have to make do with the ones that came with the kit. torn between opening the TEEMU chassis and ordering the BMI chassis any thoughts? also have you tried the new improved "heavy duty as they say" front one-ways? might order it next from schumacher. cant wait for the weekend to try out the car! btw, you e-mailed me your set-up a few months ago, its the one i have on my car now and i'm pretty sure you've made some changes... mind mailing me a new one? many thanks!
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Old 07-04-2005, 12:24 AM   #10190
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Generally running less than the standard riser plate will give you more traction on that end of the car. However, there are situations where it can give you less traction. Unfortunatelly there is no way to tell until you try the other options and know what to look for. What you are dealing with in this case is not an increase or decrease of rear traction. You are dealing with a increase or decrease in front traction because your chassis is able to roll more because of the rear roll center change. By allowing the "rear" to roll more you inadvertently are transfering more weight (left and right) on the front end also (remember it is a stiff chassis right?). This should be why you got more steering. Unfortunately, NO ONE can tell you what an adjustment is going to do. They can only give you advice, and their personal experience.

Ignaranuses can stop reading at this point.

This is why people get confused when they make an adjustment and the car doesn't do "what it is supposed to". As if the car has a mind of it's own and it is secretly plotting against you. "Fu## no I won't do what cha told me!" The car does exaclty what it is supposed to do with the setup it has on, unless it is broken, it has no choice. When it doesn't work the way you expect, it is because you don't understand what is happening. These are, as far as I am concerned, the most important tuning experiences you can have. This is because you are forced to understand that which doesn't make sense.

(Okay, now in your best yoda impersonation repeat after me- "Smart you will become, for now you are not.)

Anyways, Schumacher makes (made) many sets of alloy blocks that will fit on the Mi2 (mostly from the fireblade series of cars). When did you buy the blocks? (are they new?) The best thing to do is measure it by holding the chassis verticle (rear end down, body mount off) on your tweak board and use a camber guage to tell you how much toe you have.
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Old 07-04-2005, 01:51 AM   #10191
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Originally Posted by Jay Dub
This is because you are forced to understand that which doesn't make sense.
How can you understand something which doesn't make sense?

I am confused as to why there seems to be two schools of thought on just about every item that can be adjusted on a car.

Surely adjustments are constant between car manufacturers? I mean, if I put harder springs on the back of my Mi2, then shouldn't this be the same as putting harder springs on the back of an Xray, Yokomo or whatever

Castor is one adjustment that no-one seems to agree on. You read that running less castor increases turn-in, then you read somewhere else that it increases corner-exit steering - how can both be right??

You mentioned that no one can tell you what an adjustment does - in that case, if your car isn't working too well, how do you know where to start making adjustments?, and just as important, how do you which way to make those adjustments?

And if the change "felt" the same (or the laptimes are no different) then what did it do??

I am a very experienced off roader (but never too good at setups), but a newbie when it comes to touring cars, and frankly, I'm baffled

At least one of the good points of forums like these is that there is advice available when you are stuck, and of course you can just copy someone's entire setup (which I'll be doing once I get some Tamiya shocks )
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Old 07-04-2005, 02:35 AM   #10192
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hey ppl some guy says that the mi2 is the same as the 415 the chassis dsign etc is totally differnt right
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Old 07-04-2005, 07:55 AM   #10193
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Greetings to all!

I know for a fact that Schumacher produces one of the best r/c cars in the market today but this RAYMAN guy or whatever he is thinks of the mi2 as something else. He’s posted on the rookie zone thread, specifically on the “Does TT-01 have potential” thread a very nasty view on the mi2. Lots of guys and newbies like me occasionally monitor this thread and I hate to see a guy with a very big ego spreading nasty gossip to guys like us of things that he doesn’t even know of. I hope you guys could enlighten this RAYMAN on his perspective and straighten him out. I’ve seen the mi2 on our local tracks and I can truly say that is one of the best touring cars when in good hands.

Here’s the link to the thread and its thread number 219.

http://rctech.net/forum/showthread.php?p=1678952
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Old 07-04-2005, 08:58 AM   #10194
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Originally Posted by XTREMERCHOBBIES
ok... i will put back the riser in the rear then, leaving the front without it. i'm sold out with the carpet tower already and will just have to make do with the ones that came with the kit. torn between opening the TEEMU chassis and ordering the BMI chassis any thoughts? also have you tried the new improved "heavy duty as they say" front one-ways? might order it next from schumacher. cant wait for the weekend to try out the car! btw, you e-mailed me your set-up a few months ago, its the one i have on my car now and i'm pretty sure you've made some changes... mind mailing me a new one? many thanks!
Carlo D.
mail to: deonysius@hotmail.com
I'm working on good outdoor setups for the BMI chassis right now. As soon as I get something I'm like a lot, I'll post it up. As far as the heavy duty one-way, the only place I'll run a one-way is SoCal raceway in Huntington Beach. It's a very unique track. The only thing that's fast there is a oneway on any car. Yet it's a tight little indoor asphalt, high bite track. And I run the standard one-way when I do race there.
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Old 07-04-2005, 09:51 AM   #10195
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i have used up two sets of one-ways and broke broke both when i jumped an apex... the local track i'm running has high traction, not as big and has a 112ft straight... the SPOOL just isn't enough on turns YET, i ain't giving up this time! my JRXS made it with a SPOOL and so my Schuey should too! will be looking forward to your new set-up... thanks JK
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Old 07-04-2005, 09:54 AM   #10196
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Quote:
Originally Posted by bender
How can you understand something which doesn't make sense?

I am confused as to why there seems to be two schools of thought on just about every item that can be adjusted on a car.

Surely adjustments are constant between car manufacturers? I mean, if I put harder springs on the back of my Mi2, then shouldn't this be the same as putting harder springs on the back of an Xray, Yokomo or whatever

Castor is one adjustment that no-one seems to agree on. You read that running less castor increases turn-in, then you read somewhere else that it increases corner-exit steering - how can both be right??

You mentioned that no one can tell you what an adjustment does - in that case, if your car isn't working too well, how do you know where to start making adjustments?, and just as important, how do you which way to make those adjustments?

And if the change "felt" the same (or the laptimes are no different) then what did it do??

I am a very experienced off roader (but never too good at setups), but a newbie when it comes to touring cars, and frankly, I'm baffled

At least one of the good points of forums like these is that there is advice available when you are stuck, and of course you can just copy someone's entire setup (which I'll be doing once I get some Tamiya shocks )

It's because it depends on front end geometry, roll center, camber link length, camber link height, front spring stiffness. All of these things can change the vertical angle of the tire as the car enters and exits corners, so with different amounts of each, it can very the effect of tire angle and weight on each of the four tires.

Here are the basics of what determines the balance of a car through a corner, the weight of each of the four tires, the angle to the ground of each of the tires. These (and also a couple of other things I am leaving out for simplicitys sake) are what determine the slip angle of each of the tires, which is the direction the tire is pointing vs. the direction the car is going.

Lets say your comming off a straight into a tight corner that requires a little braking going in. The front spring will allow the front of the chassis to lower under decelleration, this puts more weight on the front end but not necessicarily more weight on the front tires, since instead of pushing the front tires into the ground, it compresses the spring. But as the front suspension compresses, it lowers the front roll center, allowing more body roll on the front of the car. The camber gain of the front geometry kicks in and leans the tires in. Then you begin to turn into the corner and the caster you have straightens the tires up and maximizes contact patch. And your car turns into the corner hard.

If you change one setting, it can effect the way the other whole system works together and will change the balance on the car. Example, if the front end was stiffer, the suspension wouldnt compress as much, the roll center will stay higher, the camber wouldnt change as much. and the car would need less caster to keep the tire within optimum camber range.

The key, as JW said, is to understand what the car is doing and what changes will help it do what you want it to. This is also why we ask for the whole setup when people ask for help tuning their cars.
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Old 07-04-2005, 09:58 AM   #10197
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Quote:
Originally Posted by Jon Kerr
I'm working on good outdoor setups for the BMI chassis right now. As soon as I get something I'm like a lot, I'll post it up. As far as the heavy duty one-way, the only place I'll run a one-way is SoCal raceway in Huntington Beach. It's a very unique track. The only thing that's fast there is a oneway on any car. Yet it's a tight little indoor asphalt, high bite track. And I run the standard one-way when I do race there.
the set up's should change too much when running the BMI chassis should it? Mo has been running his since the Reedy and the usual set up's still work on the car. When I get mine I will try my latest set up with the chassis and see how it feels.
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Old 07-04-2005, 10:01 AM   #10198
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Well said Jack
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Old 07-04-2005, 10:04 AM   #10199
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Originally Posted by STLNLST
the set up's should change too much when running the BMI chassis should it? Mo has been running his since the Reedy and the usual set up's still work on the car. When I get mine I will try my latest set up with the chassis and see how it feels.
The setup Donny and I have been running out here with the stock chassis was way too stiff and kept the car way too flat for the stiffer BMI chassis. It didn't have enough chassis roll and it would loose grip suddenly. We're working on getting more roll into the car without making it lazy in the left to right transitions.
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Old 07-04-2005, 10:11 AM   #10200
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Quote:
Originally Posted by Jon Kerr
The setup Donny and I have been running out here with the stock chassis was way too stiff and kept the car way too flat for the stiffer BMI chassis. It didn't have enough chassis roll and it would loose grip suddenly. We're working on getting more roll into the car without making it lazy in the left to right transitions.
The BMI chassis is stiffer than the stock chassis but we have had the thicker 2.5 adjustable chassis so if wasn't a huge switch when Mo got his BMI. At last years Reedy race I ran the 3mm PDub chassis. My set up is fairly light as is and I'm running the 2.0 chassis. For next weekends Revo race I'm thinking of putting the 2.5 back on.
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