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Old 12-05-2008, 05:40 PM
  #6286  
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Hey Jason, here is my current set-up(I think this is what i am running anyway.... I keep a binder of all the changes i make to my cars and well i lost my binder)
So, this is what i can remember
nothing on the kingpins-> didnt like it with the 5K
.020 Linear spring
Angled Servo
25wt oil in the rear with the red spring
The standard shock ball end with 2mm of shimming
middle battery placement
10K in the tubes
Parma magenta tires all the way around, right outta the box
speed 12 body
Everything else is right outta the box.
Its running on medium-high traction carpet that is smooth in some spots and bumpy in others. The track is only up for a night then gets torn down. Its fairly tight being only 50x24.
At the beginning of the night i sauce the whole front tire, then the next heats i only sauce the inside half.
We are running 27t/13.5 motors. I am waiting for my speedo and motor to show up. Currently i have a t-bang 27t geared at 23/88 (i think)

I think that is everything. I hope this helps and any help you fellows can post about my mid-corner "chassis rollover" will be greatly appreciated.
The customer support for the BMI car is crazy wicked and its not just from Jason but from everyone running the car.
Thanks again,
Anthony
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Old 12-05-2008, 05:52 PM
  #6287  
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Hey lowrider, try this setup. I run on a similar sized track as you. One thing I did notice. You run full size tires right out of the box. How sharp are the sidewalls? A sharp corner on the edge of the tire will increase the chance of traction roll.

Originally Posted by schreff
Here's what I ran this past weekend at 360 Raceway with the updated car...

-Front-
4 deg caster
5 deg reactive blocks
-1.25 deg camber
.020 BMI spring
.010 spring sag
#3 SureLube on king pins
servo on angled mounts (gonna try flat next time out)
Parma Magenta tires (41.6mm)

-Rear-
Hot Bodies shock w/ Losi 40wt oil and ASC gold spring
ASC shock mount raised with 2mm shims and medium ball stud on shock mount
shock all the way back on chassis
battery full forward
.070 side plates
#4 SureLube in damper tubes
Parma Grey tires (43.6mm)

Use whatever shims/ride height adjusters to get 4mm ride height. I also ran a Parma Speed 8 LW body since I was running 17.5.
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Old 12-05-2008, 06:33 PM
  #6288  
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Originally Posted by lorider75
Hey Jason, here is my current set-up(I think this is what i am running anyway.... I keep a binder of all the changes i make to my cars and well i lost my binder)
So, this is what i can remember
nothing on the kingpins-> didnt like it with the 5K
.020 Linear spring
Angled Servo
25wt oil in the rear with the red spring
The standard shock ball end with 2mm of shimming
middle battery placement
10K in the tubes
Parma magenta tires all the way around, right outta the box
speed 12 body
Everything else is right outta the box.
Its running on medium-high traction carpet that is smooth in some spots and bumpy in others. The track is only up for a night then gets torn down. Its fairly tight being only 50x24.
At the beginning of the night i sauce the whole front tire, then the next heats i only sauce the inside half.
We are running 27t/13.5 motors. I am waiting for my speedo and motor to show up. Currently i have a t-bang 27t geared at 23/88 (i think)

I think that is everything. I hope this helps and any help you fellows can post about my mid-corner "chassis rollover" will be greatly appreciated.
The customer support for the BMI car is crazy wicked and its not just from Jason but from everyone running the car.
Thanks again,
Anthony
Hey Anthony,

Go to 35-40 wt. oil in the center shock and cut your tires down some. I run mine at around 1.750 in the rear and 1.670 in the front. For real high bite i go to 1.7 rear and 1.630 front. Make sure you have your ride height around 3.5mm. Go to 20,000 in the tubes and 10,000 on the kingpins. You should be good to go.
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Old 12-05-2008, 09:38 PM
  #6289  
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Just finished building my Silva shock Wow is it smooth! I did notice though when the shock is compressed quickly I think I feel the bladder compress then pop back. I remember years ago some people where putting little pieces of foam between the bladder and the shock cap on some shocks and was thinking of maybe some cotton or something in this shock. It will probably work just fine as is and doesn't need any modification...but I just like to tweak every little thing...what you guys think?
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Old 12-05-2008, 10:23 PM
  #6290  
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Adding foam between the bladder and cap will add rebound, which i dont think you want to gain. If anything trying to find a 'stiffer' bladder would be best.
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Old 12-06-2008, 01:11 AM
  #6291  
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Originally Posted by InspGadgt
Just finished building my Silva shock Wow is it smooth! I did notice though when the shock is compressed quickly I think I feel the bladder compress then pop back. I remember years ago some people where putting little pieces of foam between the bladder and the shock cap on some shocks and was thinking of maybe some cotton or something in this shock. It will probably work just fine as is and doesn't need any modification...but I just like to tweak every little thing...what you guys think?
Gadget,
I've built a few of the Silva shocks and one problem with them is that there is too much space between the eclip grooves on the shaft, which allows the piston to move up and down as the shock compresses and returns. You can really feel it as a little 'pop', so I bet that is what you are noticing there. You can add a 2mm id shim (slot car armature size) between the eclip and the piston or just glue it in place to get rid of the 'pop' Truth is, I don't think this piston play is fine at all, as it takes up a lot of the movement that the shock uses in normal travel on the track
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Old 12-06-2008, 02:28 AM
  #6292  
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That's exactly what I am noticing...I'm sure I can find something to shim it...thanks!
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Old 12-06-2008, 03:31 AM
  #6293  
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Well that was it thanks OD...I couldn't find a shim so I was trying to make one out of some thin plastic when I noticed one of the E clips I took off was bent out of shape. The E clips used just don't seem to fit right, I think they are too small for the groove. Anyway, I remembered I had an HB shock and that they had the same sized shaft so I thought I would replace the E clips with the HB ones. Turns out the HB ones are thicker too and take out all the play on the piston without having to shim or glue it. The shock is smooth as butter now
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Old 12-06-2008, 03:53 AM
  #6294  
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Here in the Uk we are lucky enough to have high bite carpet to run on, and after reading Jason's post about running his servo flat on carpet it sounds like it would help smooth my car out.

Question is, I'm not sure on how I should be mounting the servo, obviously I realise I have to turn the servo mounts round the other way but which holes do I use, and should I fit the turnbuckles front or rear on the servo saver etc.

Be grateful if someone could offer I bit of help here, a picture would be cool as well.

Thanks guys
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Old 12-06-2008, 05:51 AM
  #6295  
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Mount it as low as possible and turnbuckles in front.
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Old 12-06-2008, 08:06 AM
  #6296  
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Originally Posted by terryh
Here in the Uk we are lucky enough to have high bite carpet to run on, and after reading Jason's post about running his servo flat on carpet it sounds like it would help smooth my car out.

Question is, I'm not sure on how I should be mounting the servo, obviously I realise I have to turn the servo mounts round the other way but which holes do I use, and should I fit the turnbuckles front or rear on the servo saver etc.

Be grateful if someone could offer I bit of help here, a picture would be cool as well.

Thanks guys
Here ya go. Originaly I ran with the servo mounted to the front chassis hole with the arms to the back of the saver. However with that set-up the servo mount ears are smashed against the front lower arms.
Attached Thumbnails BMI's DB12R-img_1415.jpg   BMI's DB12R-img_1416.jpg   BMI's DB12R-img_1417.jpg  
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Old 12-06-2008, 08:40 AM
  #6297  
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Originally Posted by mrrcguy
Here ya go. Originaly I ran with the servo mounted to the front chassis hole with the arms to the back of the saver. However with that set-up the servo mount ears are smashed against the front lower arms.
Just what the doctor ordered, top stuff thank you
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Old 12-06-2008, 11:52 AM
  #6298  
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I ran mine in front like mrrcguy but that was because I never liked how the steering links can hit the servo before full servo lock. But with 1/12th you won't be using that much steering so it really isn't an issue. Most setups have the servo foward and the links behind the servo saver. With my rebuild to the 12RR I will be trying the servo more foward to see how it effects steering.
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Old 12-06-2008, 12:49 PM
  #6299  
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mrrcguy,

What lipo batteries are you using?
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Old 12-06-2008, 01:31 PM
  #6300  
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Its a 2000mah 7.4 15C from Common Sense RC. I does not have a hard case, but in the BMI cars the pack is extreemly well protected so I dont be a problem with it. The pack is small enough to get the weight right where you want it. Im running a 21.5 and as long as you dont push the gearing limits run time is not a issue. In fact you can gear to a point that makes the car even with a 4cell 17.5 car and the you get about 10 minutes of runtime.
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