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Old 08-22-2009, 09:42 AM   #796
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How will you take care of LVC?
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Old 08-22-2009, 12:47 PM   #797
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Nitride (or ceramic) bearings are fine. My thoughts on wheel bearings is that they die from impact. They get brinneled or have tiny divits put in the races by the balls from an impact. Ceramic balls are harder and may make this worse. Use the ceramics everywhere but in the wheel bearings. I like rubber seals which is the other main wear factor in wheel bearings. Dirt entry. Keep it out with seals. Let the factory guys wear their stuff out with non contact bearing seals.

We are running the International Indoor Champs weight spec for rubber tires which is 1425 grams instead of Roar 1500 g. This allows a benefit for the lighter LiPos. Not much ballast now. I have not dumped. This would be the only reason to add more compexity and weight with a second battery pack. The amp draw of the fans is not enough to affect performance on the car.

Who is that LVC

Have had real good luck with Jaco blues on the hot asphalt. give it a try. Very nice looking prism wheels.

Last race was a tire disaster for me. I did come in second. Jaco blues will help me next time. I had an unoticed rear A-arm that was bent from my Tekin high speed crash in reverse (before I locked it out). This had ruined my rear toe-in setting and my rear traction.
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Old 08-23-2009, 01:44 AM   #798
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Low Voltage Cutoff, when you connect fans direct to small lipo pack it will be easy to go under allowed voltage and possible to have small pack killed.
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Old 10-20-2009, 04:33 PM   #799
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This thread has been silent for a while as I was bedeviled with an ill handling car. Ever since Our new asphalt. Here were the symptoms. the car would weave on the straight, The car would veer off line on brakes. Sometimes all the way to the boards. I was on only 65% brakes. The car accelerated crooked, often to the boards on any excess of throttle. This allowed only a delicate driving approach. I was slow. Here are things I checked and possibly the order you might do the same with similar problems.

Weight balance, both side to side, and corner weights with scales, set to perfect.
Caster blocks replaced,
Servo saver replaced,
Front arms replaced.
Servo changed and then changed back
receiver changed.

Nothing had helped.

Last night I noticed that the motor axis was slightly off perpendicular by inspecting closely the gears. I had bent the plate and then straightened it (almost all the way) the first day of the new layout. There was a new chicane with flapper bolted to a concrete 6x6. I compressed the flapper to solid rock by habit. I have never bent a motor plate before. Yesterday, I shimmed the motor only .015 inch with a thin washer between the lower motor bolt and the motor plate. I also restraightened the plate. Success, no weaving, Straight acceleration at full throttle, 100 % brakes were possible. I have also made a bunch of other needed changes so I thought I would list them.

I abandoned X-ray axles up front. The outdrives needed to be made too thin for this too work. They broke often where previously they did not break much at all. I am using the TIR locked diff with Nylon Outdrives. The x-ray axles were mated to X-ray hubs, bearings and opened up Associated caster blocks and arms.

I had some dramatic oversteer during the last race. I took the locked diff out, tuned the car in a very straight forward manner. Put the locked diff back in and I was good. I had several mistakes setting rear toe. I measure it with my camber guage and the setup board now and set it to 2.5 degrees per side.

The car felt a little tippy. I lowered the front to 5 mm and added back the thick sway bars front and back.

Acceleration out of the corner was lacking with a 3.5 that the previous track liked. I tried degearing but just got slow, I demotored and geared up an LRP 4.0 to a 25 pinion. I had great punch out of the corners now. The tires were not slipping, I got a good wear pattern finally (tiny ripples lined up with the circumference). This came along with better cornering from not having overheated tires. I used Traction Action tire prep. Motor temp 160F at 6 minutes. Modest outdoor temp.

Here is the final setup for virgin (not sealed) asphalt.

LRP 4.0 90spur/25pinion, Thunderpower 40 C 5000 mA-h pack
Integy motor fan, LRP fan on Tekin Speed control
Manutech Battery tray, offset and adjustable.

Front
4 degrees caster
5 mm front ride height
Blue spring 2cnd hole in
Heavy sway bar
0 toe in
Front camber link inner, innermost hole and downward hole
1/8 inch spacer on steering outer pivot ballstud to correct bumpsteer.
35 weight oil, .010 bevel on top of piston holes.
Ackerman stock
Front arms forward


Rear 6 mm ride height
silver spring 4th hole in
heavy sway bar
2.5 degree toe in per side rear
rear outer camber link one washer under ball stud (at wheel)
rear inner camber link, in and middle
35 weight oil, .010 bevel on top of piston holes
Rear arms back.

CS 32's

Tekin RS Pro
Report on the Tekin-It thermals easier than an old LRP TC edition. It has not caught fire like a new LRP SXX. It should have a built in fan and heatsink. Instead I have to run it on the side and blow air on the bottom and solder posts. The best so far on my pan car a Tekin R8. A little on the chunky side but receivers are very tiny now to compensate.
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Last edited by John Stranahan; 10-21-2009 at 12:24 AM.
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Old 10-20-2009, 06:56 PM   #800
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Thanks for your update John, I have a couple of questions, What would be the theory behind a bent motor mount causing your problems and I've noticed a lot of the setups you see now the the wheelbase is run long as you have with your latest setup, why do you think this is.
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Old 10-20-2009, 08:59 PM   #801
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The motor has considerable gyroscopic action. I suspect with the axis off perpendicular it was giving me some torque steer when I accelerated and decelerated, (the car was loading up a front corner or a rear corner) just enough that with difficult traction and a high powered motor, I could not compensate. We have a TC3 at present with the same condition. Almost undriveable with a 3.5 for a guy the same age as myself. I'll see if there is ever a cure as the torque steer with the Tc3 is a constant and a given. I have no other explanation for the remarkable cure. I ran the track just Sunday with no rain in between and still had my problems. The track was the same.

I put the wheelbase long just because I am on a long course with fairly large radius turns. I need stability from length rather than nimbleness for the twisties.
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Old 10-21-2009, 05:28 PM   #802
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The straightened TC5 continues to improve. I mounted my Tekin R8 and an LRP X12 3.5 right out of my wide pan car onto the TC5. The fit was excellent. There is even room to move the control forward 1/8 th inch to give the motor cooling clearance. I ran a pack with 21/90 gearing. I had no significant forward tire slip out of the corners. Mid leg acceleration was outstanding. I could use just a bit more punch off the corner. Motor temp 110 F. Speed control temp 105 F. Hardly working the system hard yet. I geared up a tooth to 22/90. Motor temp 128 F at 6 minutes., speed control temp 110F. Air temp about 86F. This is certainly the system to run in the heat at present. (I had troubles with this speed control and a Novak Ballistic 3.5. When it goes into sensorless mode at medium speed it just went to a slow throttle. It works OK with LRP). The Thunder Power battery continues to shine. No swelling ever, even in the pan car pulling 50 amps. Don't put the SMC 6000 pack in this type of rig. It will overheat at 122F and swell up badly.

The car continued to brake beautifully straight with 100% brakes and accelerate in a straight line even if I slipped the tires a little coming out of the corners with the 22/90 gears. Speed on the straight was outstanding.

Here is a pic. I have left it a little large so you can click on it again and scroll arround. Note, Perfect side to side balance and corner weight balance. Fans mounted direct to battery for full voltage. Huge Novak Capacitor added to Tekin R8 for heavy duty use. Manutechracing.com tray in custom holes all the way out. Note extra cross tape strap. Receiver capacitor. Integy motor fan heatsink with Novak fan. The Integy fan will not last.

Ready to race Sunday. 1464 g with body.
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Old 10-27-2009, 04:33 AM   #803
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What type of banana plugs are you using there? Im looking for something larger than 4.0mm and where did you get them?

My mod car keeps melting the solder on the banana plugs, i replace/retension all the time, im over it, need something that can handle the power.

Ive got an sxx with a sp comp3 4.0t.

Thanks
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Old 10-27-2009, 08:17 AM   #804
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zharn, for high capacity connectors, these are the two prime choices:
http://www.rctoys.com/rc-toys-and-pa...RS-WIRING.html
http://www.rctoys.com/rc-toys-and-pa...RS-WIRING.html
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Old 10-27-2009, 08:17 AM   #805
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I don't like banana plugs for the very reason you mention. When the plug gets hot from inadequate spring tension and surface contact then the spring (the fingers) overheats and loses its temper. Then you may start seeing the problems you describe. It does not help to pull the fingers out. They are in because they have gotten too hot.

I like to buy packs with pigtails (WS Deans). Then I add Deans connectors that have been cut in half. This lets me use big neat looking shrink wrap. the unmodified Deans connector works just as well and can handle the big amps.
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Old 10-27-2009, 11:10 PM   #806
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Ok, thanks for the info. Where is a cheap place to get the thunder power 40c batteries from? Cheapest ive seen is $125 usd.
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Old 10-28-2009, 09:14 AM   #807
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That's about right. I have not seen them for less.
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Old 10-28-2009, 08:19 PM   #808
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You could try emailing rctoys.com . They might give you a deal. At the very least you'll get free shipping.
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Old 06-22-2010, 05:48 PM   #809
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Default TC5 Lipo Tray Holder

sup yaal, need some help....
is the assoc lipo tray -- would that fit my serpent s400 touring electric car?
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Old 06-23-2010, 12:14 AM   #810
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Quote:
Originally Posted by ericbeenorcal View Post
sup yaal, need some help....
is the assoc lipo tray -- would that fit my serpent s400 touring electric car?
I don't see any problem, maybe you will need new holes.

It is only piece of carbon

In my tc5 I move outside holes about 7-8mm, because I flip/flop belts and
my lipo must go a little outside for balance

Wish you good luck
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