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Old 07-05-2009, 03:13 PM   #7531
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Hey guys, so I got my LiPo chassis (and replacement flex plate ball cups) in and all installed.

The setup is:
BMI DB12RR-LiPo Chassis w/ SMC 1S 25C LiPo with custom leads.

Front:
Flat Servo in the forward position
.20 springs
5 Deg Caster block @ 4 deg position
-1 Camber
Jaco Prism Black Foam @ 1.68"
4mm Ride height

Mid:
Gold Spring
Silvia Shock W/ 60 Weight oil
Darkside racing front shock mount at mid position (equal to about the med ball stud w/ 2mm shims position on the stock mount.)
4mm Ride Height
Standard RR Flex plates at the long position
Dampener tubes with 5000 weight diff lube in them

Rear:
4mm Ride Height
Jaco Yellow rears trued to 1.75"
Orion Vortex 2 Race 10.5T BL
46 Pinion / 78 Spur

Total weight with a heavy duty body : 740gm.


The car was responsive, easy to drive, fast, and transitioned side to side very well... Not twitchy or nervous at all to drive. No pronounced push, and no double steer. I was very rusty at driving so I didn't get its all out of it.. but the car was fast and very easy to get used to.

In the pic you can see I am running a GTB 4 cell ESC with the big cap, and a Hobby King Voltage booster hard wired into the ESC lead and attached to the Rx. Most of the heavy items are pushed back. I didn't move the RX back because the way I saw it this caused some bad geometry with the steering to result.
Attached Thumbnails
BMI's DB12R-p7050015.jpg   BMI's DB12R-p7050016.jpg   BMI's DB12R-p7050018.jpg   BMI's DB12R-p7050020.jpg  
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Old 07-05-2009, 04:00 PM   #7532
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The BMI chassis fits the SMC packs like a glove and I love it. But I am curious about the new Thunderpower packs that look to be square - no bumps - and a tad wider than the SMC spec size. (about 1mm) Anyone have one of these in a BMI chassis? Curious how the fit is with the square cut out on the chassis.
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Old 07-05-2009, 09:04 PM   #7533
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haha my bad.. double post hours after the original.
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Old 07-06-2009, 08:25 AM   #7534
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Clegg.....Black front and yellow rear? Are you doping full front? Cant believe your not pushing to the boards with that far of a split on compounds.

DK
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Old 07-06-2009, 09:20 AM   #7535
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Quote:
Originally Posted by PartTime View Post
Clegg.....Black front and yellow rear? Are you doping full front? Cant believe your not pushing to the boards with that far of a split on compounds.

DK
The track I run on is pretty high bite ozite, and yeh thats with full coated fronts. Lilac, Purple and 2x Pink work also but I have terrible issues with them fuzzing later in the run. Black seemed to be a little more pushy than the stickier compounds, but kept that grip much more consistent than the others that fuzz over and gum up.

the push i do get from the blacks is very stable and reasonable, some may not like it, but I'd rather have a car with a very slight push than a car that had oversteer issues or dynamic traction as the race goes on.
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Old 07-06-2009, 10:42 AM   #7536
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Quote:
Originally Posted by Clegg View Post
The track I run on is pretty high bite ozite, and yeh thats with full coated fronts. Lilac, Purple and 2x Pink work also but I have terrible issues with them fuzzing later in the run. Black seemed to be a little more pushy than the stickier compounds, but kept that grip much more consistent than the others that fuzz over and gum up.

the push i do get from the blacks is very stable and reasonable, some may not like it, but I'd rather have a car with a very slight push than a car that had oversteer issues or dynamic traction as the race goes on.
I have run black/gray and love how consistant they are but black/yellow? If you say it works then I will take your word for it. Im running magenta/pink now. I like the pink rears, good traction/wear and harder to chunk then yellow. Thinking dblpink or purple up front with the thin L-plate and full dope frt/rear. Still in testing stages. Not sure where its gonna land.

Im racing wed and will post what I find on the second race with the car. Either way this is the best lipo car I have tried and its only one race old..and its the old R chassis ! Cant wait to see how it acts after being dialed in. Then the upgrade to RR.

DK
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Old 07-06-2009, 10:56 AM   #7537
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Quote:
Originally Posted by PartTime View Post
I have run black/gray and love how consistant they are but black/yellow? If you say it works then I will take your word for it. Im running magenta/pink now. I like the pink rears, good traction/wear and harder to chunk then yellow. Thinking dblpink or purple up front with the thin L-plate and full dope frt/rear. Still in testing stages. Not sure where its gonna land.

Im racing wed and will post what I find on the second race with the car. Either way this is the best lipo car I have tried and its only one race old..and its the old R chassis ! Cant wait to see how it acts after being dialed in. Then the upgrade to RR.

DK
I have found gray and yellow to be very close on feel. the Yellow just have a bit more bite when I get on it it seems. The yellows tendancy to chunk is less than optimal though. Magenta and Pink is what I have heard some others use... I may try that at some point.
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Old 07-06-2009, 02:58 PM   #7538
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My car is on the way, tomorrow i see in the track, is in Post Office กกก
Generally, i use Purple, Lilac, in front and Pink, magenta rear.
Magenta-magenta, work good for open tracks, and magenta-grey, in high traction thecnical tracks.

Greetings, Luis C.
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Old 07-07-2009, 06:33 AM   #7539
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Got a question: I just started building my new DB12RR last night and noticed the different front spring setup compared to the typical AE springs. What advantage do the larger diameter springs give to the car versus the smaller AE style springs?
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Old 07-07-2009, 07:54 AM   #7540
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Quote:
Originally Posted by Fuzzy View Post
Got a question: I just started building my new DB12RR last night and noticed the different front spring setup compared to the typical AE springs. What advantage do the larger diameter springs give to the car versus the smaller AE style springs?
for a given spring rate and wire diameter, a smaller spring diameter requires more coils.

thats why these larger diameter springs have so few coils, to me this is a benefit because the more coils will become coilbound sooner for the same free length.

there may be other reasons, but i think you get a shorter spring with more available travel.
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Old 07-07-2009, 09:49 AM   #7541
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Originally Posted by avs View Post
for a given spring rate and wire diameter, a smaller spring diameter requires more coils.

thats why these larger diameter springs have so few coils, to me this is a benefit because the more coils will become coilbound sooner for the same free length.

there may be other reasons, but i think you get a shorter spring with more available travel.
There definately is more travel to the front springs. We went with the larger diameter and less coils for a few reasons. The main reason is that the AE style springs are prone to failure as it uses a small coil diameter which has a tendency to allow the spring to fail or collapse. They become much more progressive being wound at suck a tight diameter and the wire actually is under much more stress and the spring reaches its binding point. We also were after a more linear spring rate. You dont come close to coil bind under compression of the front end. With that, the spring has less of a chance of failure. Then add to that, we preset the spring lengths to assure that they will not collapse.
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Old 07-07-2009, 01:21 PM   #7542
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Got a question. I have crc lower arms on my car. Do the AE lower arms fit? Is there a performance advantage to either?

DK
Edit: found out there IRS lower arms, not crc. So they are the same arms fit wise but is there any handling differents?

Last edited by PartTime; 07-07-2009 at 04:14 PM.
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Old 07-08-2009, 05:18 AM   #7543
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Quote:
Originally Posted by PartTime View Post
Got a question. I have crc lower arms on my car. Do the AE lower arms fit? Is there a performance advantage to either?

DK
Edit: found out there IRS lower arms, not crc. So they are the same arms fit wise but is there any handling differents?
The AE lower arms will fit fine. They will need to be cut where they mount to the chassis to run very small tires. We do offer AE cut arms if you are interested.
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Old 07-08-2009, 10:18 AM   #7544
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Quote:
Originally Posted by PartTime View Post
Got a question. I have crc lower arms on my car. Do the AE lower arms fit? Is there a performance advantage to either?

DK
Edit: found out there IRS lower arms, not crc. So they are the same arms fit wise but is there any handling differents?

I dont know of any difference in the handleing aspect, thay just allow you to run the tires down to the rim if you choose.
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Old 07-08-2009, 10:28 AM   #7545
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The other nice thing about the IRS arms is they are universal left to right. So when you break an arm your spares will fit on either side.
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