BMI's DB12R
#6691
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Join Date: Jan 2004
Location: Outside doing things in places... Denver, CO
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My setup: (editing Jasons setup)
Front:
5 degree block w/ 4 degree castor
.020 linear springs and 30K on the kingpins
3.5mm ride height
servo flat w/ medium ballstuds on the steering blocks
Lilac front tires (Jacon Prism stock height)
.25mm droop (I think this is how much droop, but not exactly sure - I was in a rush when I was testing this)
Servo mounted forward with the ball studs on the back of the servo saver
-1.5 Deg Camber
Neutral Toe
Rear:
Gold center shock spring
Silva shock w/ 60 wt Trinity oil
Medium ballstud on shock mount w/ 1.5mm worth of spacers
batteries in the middle
30K in the tubes
Stock flex plates mounted in short position
no tweak screws
Yellow rear tires (at full Jaco Prism size)
172mm rear width
1mm pod droop
Pod Level at ride height
4.0mm ride height
Novak 17.5 BL
Pinion: 45
Spur: 78
Body - Protoform Speed 12
I have 10K and I have 30K silicone, and the hobby store says they cant order 20K cause they cant find it. They also dont know know where to get Sure lube from. Not entirely sure I am going to start experimenting and mixing 10 and 30K to get 20K.
#6692
How tight is your track layout??
The one thing I really dont like doing is setting up a car with the front and back off on ride height, I always try to make it even.
I use Kyosho 20k. Part #SIL20000. Sure Lube your hobby shop should be able to get if they can get IRS parts.
From what I can see your back end is farely hard and you should be getting a good amount of rotation out of it.
The one thing I really dont like doing is setting up a car with the front and back off on ride height, I always try to make it even.
I use Kyosho 20k. Part #SIL20000. Sure Lube your hobby shop should be able to get if they can get IRS parts.
From what I can see your back end is farely hard and you should be getting a good amount of rotation out of it.
#6694
Actually I think it is a little bit softer than 20k. Not by much though. I never go higher than red or 20k on the front end though. My track is too bumpy for it.
#6695
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Join Date: Jan 2004
Location: Outside doing things in places... Denver, CO
Posts: 4,609
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How tight is your track layout??
The one thing I really dont like doing is setting up a car with the front and back off on ride height, I always try to make it even.
I use Kyosho 20k. Part #SIL20000. Sure Lube your hobby shop should be able to get if they can get IRS parts.
From what I can see your back end is farely hard and you should be getting a good amount of rotation out of it.
The one thing I really dont like doing is setting up a car with the front and back off on ride height, I always try to make it even.
I use Kyosho 20k. Part #SIL20000. Sure Lube your hobby shop should be able to get if they can get IRS parts.
From what I can see your back end is farely hard and you should be getting a good amount of rotation out of it.
I am not seeing a terribly high amount of rotation (excessive), it seems to be pretty under control. I normally have setup cars with a .5mm rake to the front. Because normally by the end of a fast 8 min race you will knock that down to .2 or less difference front to back. If you start off with an even ride height by the end of the race you may have more rake to the rear and cause the front to push.
#6696
The track is pretty tight, theres a very tight section followed by a real fast flowing sweeper/straight.
I am not seeing a terribly high amount of rotation (excessive), it seems to be pretty under control. I normally have setup cars with a .5mm rake to the front. Because normally by the end of a fast 8 min race you will knock that down to .2 or less difference front to back. If you start off with an even ride height by the end of the race you may have more rake to the rear and cause the front to push.
I am not seeing a terribly high amount of rotation (excessive), it seems to be pretty under control. I normally have setup cars with a .5mm rake to the front. Because normally by the end of a fast 8 min race you will knock that down to .2 or less difference front to back. If you start off with an even ride height by the end of the race you may have more rake to the rear and cause the front to push.
#6697
#6698
#6700
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Join Date: Jan 2004
Location: Outside doing things in places... Denver, CO
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I carry a copy with me to refference if I am confused on how a certain change will affect the car.
#6701
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Join Date: Jan 2004
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So since 30K is too heavy. Would 10K be better to use? I have some bottles of sure lube on its way, but it wont be here till early next week.
I am half set to run the car as is on Sunday in the race... but I am curious what thinning the fluid in the damper tubes may do with such a tight rear end setup on the car.
I am half set to run the car as is on Sunday in the race... but I am curious what thinning the fluid in the damper tubes may do with such a tight rear end setup on the car.
#6702
Tech Rookie
yes I think 10k would be fine to used.. I used it on something similar and it worked fine...
#6703
Moderator
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Join Date: Jan 2004
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So whats your thoughts on a LiPo setup for the car. Preferably a setup that doesnt require massive changes going from 4 cell to LiPo. the LiPo setup is around 120 or more grams lighter in the center of the chassis.
Running a 13.5BL.
I have voltage booster in hand and am thinking of giving it a try this weekend sometime to test stuff out. Just curious what you guys would think.
I am already thinking some softer tires (Pinks in the rear dbl pink fronts) to make up for the fact that the car will be putting less weight on the tires.
Softer suspension is also going to be needed just to compensate for the lack of weight.
Running a 13.5BL.
I have voltage booster in hand and am thinking of giving it a try this weekend sometime to test stuff out. Just curious what you guys would think.
I am already thinking some softer tires (Pinks in the rear dbl pink fronts) to make up for the fact that the car will be putting less weight on the tires.
Softer suspension is also going to be needed just to compensate for the lack of weight.
#6704
Tech Champion
iTrader: (4)
The DB12RR has new longer flex plates and flex plate mounting positions in addition to the stock position that soften the suspension. This was done for two reasons. A softer side to side spring rate mellows the cars steering at super high grip races and it allows for softer suspension in case you run 3.7v lipo batts.
I wound run the car stock the frist time to see how it does with no changes.
Then I would try the following changes one at a time to see what they do.
1. Run .020 linear front springs and adjust the king pin shims so I had .5mm droop up front with the lighter battery.
2. A blue center spring with 25wt oil.
3. The stock natural fiberglass RR flex plates in the long position.
4. You will want to step down on the side damper oil viscosity.
5. You will also need to slam the battery back to get the weight distribution back to normal. Running a lighter battery is like moving a 4 cell pack forward as far was weight distribution is concerend.
With these setup the car will be very soft and should roll even with the lighter battery.
#6705
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Join Date: Jan 2004
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Thanks Adrian! Moving the battery real far back is an issue with the flex plates. Due to the squared off nature of the LiPo pack the plates seem to have interference if you move the back much beyond mid way toward the back. I will give it some testing and see what I can work out.
I am curretly running the stock flex plates for the RR in the short config, so just moving them long, replacing the center shock setup and damper tube setup is about the extent of the changes it seems.
I am curretly running the stock flex plates for the RR in the short config, so just moving them long, replacing the center shock setup and damper tube setup is about the extent of the changes it seems.