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Old 09-20-2009, 06:01 AM   #7906
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Here is the latest picture of my car.
New switch installed. This is a double pole switch. One pole switches the ESC and one switches the booster.

Battery is a SMC 4900mAh 40C. I swapped the sticker from the bottom to the top. Not sure way SMC make them this way. Same with the 2-cell packs. Maybe it's so others can't see what pack you are running

In this form with full size tires, no transponder and light weight body (40g) it weighs 726g. This is also with the Tekin RS PRO and heavy wire which adds 10g over the RS and lighter wire.
Looks good. Now you just need to cut those tires down and you will be all set.
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Old 09-20-2009, 08:22 AM   #7907
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Hey all!!
Need some help, we only starting to use LiPo in 1/12th next year in South Africa. What is the best way to do this; 1. Use Novak step up voltage to prevent LiPo cut-off from kicking in with the LRP SXX, or 2. Use a receiver pack and a voltage regulator to 6A??

Thanks,
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Old 09-20-2009, 08:33 AM   #7908
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Hey all!!
Need some help, we only starting to use LiPo in 1/12th next year in South Africa. What is the best way to do this; 1. Use Novak step up voltage to prevent LiPo cut-off from kicking in with the LRP SXX, or 2. Use a receiver pack and a voltage regulator to 6A??

Thanks,
From what I've heard - booster is better in stock classes as it takes less space, less weight, and no need to recharge between runs. In mod top drivers are usually using the receiver packs as runtime is an issue with mod.
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Old 09-20-2009, 10:08 AM   #7909
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From what I've heard - booster is better in stock classes as it takes less space, less weight, and no need to recharge between runs. In mod top drivers are usually using the receiver packs as runtime is an issue with mod.
Thanks, we only have Mod class for 1/12th here so I guess receiver pack...
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Old 09-20-2009, 11:12 AM   #7910
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Thanks, we only have Mod class for 1/12th here so I guess receiver pack...
Same here. But as I am extremely lazy, charging 2 packs after each run doesnt seem such a good perspective to me.. So I want to try out booster first with 5000mAh pack adn I think 4.0-4.5 motor should give me enough juice on a 25x14m carpet track. Will be trying this out in November.
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Old 09-21-2009, 01:18 AM   #7911
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With the bench testing i have been doing with the boosters (hobbycity and Tekin RS PRO) you will draw a maximum of 250mA (if not less from your main pack). This takes into account the efficiency of the booster and the current draw of the ESC.
If this is going to cause issues with run time then you many need to look at gearing, motor or even driving style.
Lipos aren't going to last long before they start to go soft treated like this.
Also charge time is a killer. It will take around 80 minutes to full charge the pack if you take it down to 0%.
This is charging at 1C. The slow part of the charging is the final Constant Voltage phase.
You may end up needing 4 packs to do a meet.
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Old 09-21-2009, 03:43 AM   #7912
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Originally Posted by GWH74 View Post
With the bench testing i have been doing with the boosters (hobbycity and Tekin RS PRO) you will draw a maximum of 250mA (if not less from your main pack). This takes into account the efficiency of the booster and the current draw of the ESC.
If this is going to cause issues with run time then you many need to look at gearing, motor or even driving style.
Lipos aren't going to last long before they start to go soft treated like this.
Also charge time is a killer. It will take around 80 minutes to full charge the pack if you take it down to 0%.
This is charging at 1C. The slow part of the charging is the final Constant Voltage phase.
You may end up needing 4 packs to do a meet.
250mAh sounds a LOT! CRC guys say they were using Losi 180mAh packs which were good for 2 runs without charging, so it's ~90mAh per run and if that's the case then I really rather drop 1 tooth than get a receiver pack. We are all driving 5.5 brushless + 4cell, so to keep up I think I will have to switch to at least 4.5, hope I will be able to get the 8 minutes and still keep the speed without the pack.

BTW, has anybody tried the hobbycity booster with Novak 4cell or Speedpassion GT LPF 1.1? It's wired differently than novak or BTW booster so it doesn't feed the speedo, only receiver + servo, I've heard that may cause problems with some of the speedos.. I think it's not hard to rewire it just as the TQ though..
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Old 09-22-2009, 05:49 PM   #7913
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Hey guys what are some of the other boosters for 1cell lipo other than Novak that are available and where can they be purchased. I see some mention of hobbycity booster on some of the threads. Thanks
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Old 09-22-2009, 07:08 PM   #7914
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I am using the Losi Micro-T battery which is 150mah. I end up using about 80mah per run. I need to find the 180mah battery then.
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Old 09-24-2009, 02:55 PM   #7915
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So I pulled out my DB12RR to get it ready for the next race and decided to clean up the wiring. I shortened the servo and speedo wire to the receiver. While doing this I noticed that the deans plug could be soldered right on to the solder post on the Tekin RS.
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Old 09-25-2009, 12:06 AM   #7916
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Hey guys what are some of the other boosters for 1cell lipo other than Novak that are available and where can they be purchased. I see some mention of hobbycity booster on some of the threads. Thanks
There's the TQ booster and Hobbycity.
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Old 09-25-2009, 07:14 AM   #7917
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There's the TQ booster and Hobbycity.
Which are pretty much the same booster, just one has a a wire soldered to the back instead of the pins.
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Old 09-26-2009, 12:59 AM   #7918
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BMI Parts Lists

is there a complete parts listing for both the DB12RR & BD10RR?

link please
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Old 09-29-2009, 11:04 PM   #7919
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Hi Jason,
i have been having a good time racing the 12rr with 13.5 1s lipo for the past few months with basically the same setup, but now i want to sharpen the chassis tuning to go a little faster. the setup has been very predictable and relatively easy to drive (slight push thruout the whole run) this is a carpet track with medium grip and a little bumpy in places.

the chassis setup prior to this last weekend:
Front

5 degree blocks with (centered) 4 degree castor
front width increased slightly with 2 brass shims on axles
.020 front spring w/ #3 on the kingpins
flat servo
black 42mm full sauce
1 1/2 degrees camber
0.5 toeout
3.5mm ride height
slight droop (3 shims above eyelet but springs are several months old and little sagged, maybe this is the source of laziness in the front steering due to too much droop?)

Rear
lipo centered in slots
std flex plates in long position w/o set screw
#3 in the tubes
Gold spring w/ 50 wt. oil in the silva shock
medium ballstud +2 brass shims on shock mount 1 step from most aft location (shock is pretty close to 2.95" free length)
yellow rear tire 45mm
1. to 1.5mm pod droop
3.5mm ride height
172mm wide
pod level

i have a little bump steer with the servo on center and on the smallest tires, the medium ballstuds are shimmed slightly. do you fiddle bump steer as the tires wear down?

i have been using black/yellow with full treatment front and rear. the blacks are consistent thru 8minutes but do push a little on turn in.

i tried to loosen the up the rear with short flexbars and lilac fronts, grey rears. the rear is a little slippery feeling at speed but still a little lazy in the tight slow off power corners.

do you have any suggestions on what changes to try to get more low speed steering and without it getting unsettled thru the fast and/or bumpy sections?

any insight is appreciated,
tony
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Old 09-29-2009, 11:30 PM   #7920
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Running a flat servo your going to get some bump steer, the medium ball studs help reduce it but don't completely eliminate it. Most ppl run 1/3rd to half sauce on the front so it could be the blacks are not aggressive enough since you are having to sauce the full tire. Might want to try dbl. pink. That's what I ran on carpet at the IIC.
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