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Old 03-02-2009, 03:15 AM   #7141
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Thanks buddy.
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Old 03-02-2009, 12:28 PM   #7142
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Off the start line my car pulls to the left, I have also noticed that the steering blocks are getting a little loose on the kingpin so there's a bit of play, could this be the problem?

The car is fine once it's rolling, any idea's??
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Old 03-02-2009, 03:24 PM   #7143
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Hey,
check front tire diameter is the same both sided, also for rear. If the camber is different left to right the car will pull a bit to one side. Also check ride height left to right and make sure its the same. Also under low traction conditions if the diff is too tight the back end will lose traction and swing out.
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Off the start line my car pulls to the left, I have also noticed that the steering blocks are getting a little loose on the kingpin so there's a bit of play, could this be the problem?

The car is fine once it's rolling, any idea's??
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Old 03-02-2009, 03:34 PM   #7144
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Originally Posted by terryh View Post
Off the start line my car pulls to the left, I have also noticed that the steering blocks are getting a little loose on the kingpin so there's a bit of play, could this be the problem?

The car is fine once it's rolling, any idea's??
Also make sure your axle is centered properly. It needs to be centered almost perfect. If you face the shorter boss on the clamping hub towards the bearing in the pod plate, you will need 3mm of shims per side and you will be at 172 mm and perfectly centered. This is with the offset of jaco and the new parma black wheel.
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Old 03-02-2009, 06:25 PM   #7145
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So Jason. In the DB12RR kit it comes with 3 lil brass washers to space out the rear axel. But your site sells the machined 3mm spacers. the 3 brass washers are about 1.5mm thick total (I dont have em with me). So does this mean that the kit as-is is too narrow on the back end?

I noticed when I had the 3mm spacers put in the rear wheels were stickin out from the body a bit so I went back to the 3 brass spacers.
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Old 03-02-2009, 08:05 PM   #7146
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The 3mm spacers bring the back out to 172mm when using the Jaco or the black Parma wheels. Other brand wheels have different off-sets so you need the shims to space it instead. Like with the CRC rims I believe I only had 1 shim on each side to reach 172mm.
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Old 03-03-2009, 01:25 AM   #7147
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Wow that's light, what batteries and motor are you using? I am at about 900g with mod brushless motor and 4600 mAh batteries.
Jason

I like the ".020 linear springs"
they work real good on my new front end
and i looks like they don't compresses

keep up the good work :-)

weigh
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Johnny Carey

I have be working and focus on weigh whit my car
my car T*Star12 is not the BMI car but this things
apply to all 12 scale cars, sow I hope. I don't
piss off any one here.

I have my car down to 818 grams this is whit mod motor and
Orion 4200 SHO, and Laje ESC, and my custom parts, frontend, etc.
parts.

I can get the car down to 799 grams whit my custom built motor.

Alf
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Old 03-03-2009, 03:20 AM   #7148
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Quote:
Originally Posted by Clegg View Post
So Jason. In the DB12RR kit it comes with 3 lil brass washers to space out the rear axel. But your site sells the machined 3mm spacers. the 3 brass washers are about 1.5mm thick total (I dont have em with me). So does this mean that the kit as-is is too narrow on the back end?

I noticed when I had the 3mm spacers put in the rear wheels were stickin out from the body a bit so I went back to the 3 brass spacers.
There are a few different offsets on the wheels available so i sent enough with the kit to be at 172 with a 1.5mm offset as opposed to the 3mm offset. Some wheels have no offset. I came to this decision before parma went to a 3mm offset(jaco wheel) being that jaco had just released the only 3mm offset wheel.
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Old 03-05-2009, 05:53 AM   #7149
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Do you have an editable pdf setup sheet for the 12RR? If so could someone post it or PM it to me? Thanks. Easier to keep track of the setups and changes.
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Old 03-05-2009, 08:11 AM   #7150
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BMI's DB12R
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Old 03-05-2009, 04:01 PM   #7151
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looking for some ideas on how to gain some Off-power steering. My car has great on power steering but off-power/ slow speed isnt as good.

currently have BMI .20 front springs
60 weight shock oil
Stock shock spring
sure lube 3 in tubes
ride height is 3.5mm front 4mm rear
double pink fronts and pink rears.
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Old 03-05-2009, 09:26 PM   #7152
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My first choice would be to move the battery back. Next go a step heavier on the center spring (red). Also try a little toe-out (I prefer about .020-.030). Then go to the next stiffer flex plate setting.

On our carpet I also find that Yellow rears are almost always faster than Pink. They feel like they have a similar amount of traction but allow the rear end to rotate a little more because they don't have the rubbery stick of pinks.
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Old 03-06-2009, 04:41 AM   #7153
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My first choice would be to move the battery back. Next go a step heavier on the center spring (red). Also try a little toe-out (I prefer about .020-.030). Then go to the next stiffer flex plate setting.

On our carpet I also find that Yellow rears are almost always faster than Pink. They feel like they have a similar amount of traction but allow the rear end to rotate a little more because they don't have the rubbery stick of pinks.
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Old 03-06-2009, 07:48 PM   #7154
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so a friend and I both run DB12RR's and have had the same failure of the front shock mount ball stud. When using the long alloy stud, we have found they tweak or snap in collisions. Now I know we shouldnt hit stuff... but it happens.

Both of us recently have fallen out of mains and qualifiers from failure of that front ball. Now we know this is a legacy associated bit from the 12L3 series of cars, so its not a BMI design failure. But I went and found a solid solution.

After seeing the new 12R5 center shock mount position and then looking at the 1/10th offerings out there, I picked up a Darkside Motorsports Adjustible center shock mount (#140). I rocks. In the same position as the AE mount it takes a lil more distance on the shock to give the same geometry, but overall its perfect. I used a small Ti ball stud in it and its rock solid. It has a pre threaded delrin base that fits fine.

Its probably a few gm's heavier than the AE setup, but I have no fear of busting those long ball studs anymore. And it complements the cars looks rather nicely.

I did also... somehow... bust the Silvia shock cap. I snapped the threaded portion right off. so I put an aluminum 4x40 scew through the hole with a small Oring on it, and a thin nut on the other side, and its good as new and longer which works for the darkside setup.
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BMI's DB12R-img_3826.jpg   BMI's DB12R-img_3827.jpg  
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Old 03-06-2009, 07:58 PM   #7155
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Also you can just swap it out with the long Corally ball stud which is steel
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