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Old 10-09-2007, 03:11 AM   #4201
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and you 10th in 2002
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Old 10-09-2007, 11:45 PM   #4202
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Does anyone know what's the effect of bumpsteer?
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Old 10-10-2007, 12:34 AM   #4203
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Does anyone know what's the effect of bumpsteer?
Bump steer can throw the car off line during suspension travel.

You can check bump steer by pushing the front suspension up (or go to full droop) and seeing how the wheel steers through the suspension compression. Bump steer is toe changes (in or out) to the wheels without input from the driver caused by descrepencies in the suspension/steering geometry as it travels through a bump.

It would be best to keep the wheel straight through the suspension compression to prevent the car jumping off line. Bump steer can be especially hazardous if only one side of the car hits the bump.

If you consider that the wheel unexpectedly changes direction you can see that the effect of bump steer would be to unsettle the car and possibly turn the car from your chosen line.

I think that if the wheel goes from 0 deg toe to positive (toe out) you can get the worst effects from bump steer as the car tries to pull away from itself. Say you were traveling into a left turn and your front right tire hit a bump. That is the tire that has the most load on entry into the corner and if it suddenly shoots a little straighter the car will want to scoot off away from the apex.

Wow... that turned into a bit of a ramble... I hope it helped!
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Old 10-10-2007, 02:56 AM   #4204
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That helps very much, i had no idea what bump steer meant till now
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Old 10-10-2007, 06:51 PM   #4205
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Another way to look at "Bump steer" is that it is steering caused by bumps, ie, suspension travel.



In off road, bump steer settles the car in and helps with stability, believe it or not. A car with zero bump steer can sometimes feel wandery, but with some bump in you get more consistant braking, bump out seems to favor on power steering, since out on compression equals in on extension(during droop).

Of course we are talking subtle changes, like .5 degrees, etc. for example.



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Old 10-10-2007, 08:31 PM   #4206
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but why touing need bumpsteer, if this setting is effect when bump
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Old 10-10-2007, 09:29 PM   #4207
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Originally Posted by G2B Anthony View Post
but why touing need bumpsteer, if this setting is effect when bump
Not quite sure what you mean there...
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Old 10-11-2007, 12:16 AM   #4208
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Guys I need some help
Im really beating my self up with trying to get correct gearing in my tc5
heres what I got
mm/orion 13.5
100/43
57mm tires
i'm seeing ratios of 8.+ and being told to get it at 4.00+ or - a few numbers
where is a good place to be
can someone help me out
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Old 10-11-2007, 01:36 AM   #4209
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Quote:
Originally Posted by G2B Anthony View Post
but why touing need bumpsteer, if this setting is effect when bump
You could need it when you drive on "RoadDomes" or when you car roll while turning, it affect the steering by changing toe-in/toe-out.
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Old 10-11-2007, 01:53 AM   #4210
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Originally Posted by twistedone View Post
Guys I need some help
Im really beating my self up with trying to get correct gearing in my tc5
heres what I got
mm/orion 13.5
100/43
57mm tires
i'm seeing ratios of 8.+ and being told to get it at 4.00+ or - a few numbers
where is a good place to be
can someone help me out
Your spot on now. If you have a track with lots on long straights, you may want to to lower the FDR (final drive ratio) a little more.

To get your FDR, divide Spur (100) by Pinion (43), = 2.33. Now take that ratio (2.33) and multiply by 2.0 (TC5 belt drive ratio). 2.33 x 2 = 4.66 This is your FDR.

Novak recommends a 4.5 FDR for their 13.5 Brushless, then gearing up or down based on motor temps after a 5-minute run. I'm sure Orion is in the same park on gearing for their 13.5 motor.

At my track, we have people running anywhere from a 4.3 up to 5.2 ratio. On my TC5 I ran a 104/44 = 4.72 with 59mm tires. Don't worry about the tire size too much for now, though when running the new Parma Pro 53 or JACO Przim Foam tires, your gearing ratio will need to go up a tooth or two on the pinion to accomodate for a slightly taller tire, 60.5mm initially out of the box.
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Old 10-11-2007, 05:38 AM   #4211
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THANK YOU SO MUCH
YOU ARE THE MAN!!!!!!
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Old 10-11-2007, 06:58 PM   #4212
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G2B, the beauty thing about racing, nothing is "needed", .

Things like rear toe, camber, castor, wheelbase, ride height, droop, track width, weight bias, spring rates, damping, shock valving(pistons), etc.

All driver preference. Just like the radio you use, or body, etc....you may not like a setting someone else loves!

Just another reason the racer who puts in the most effort is usually the fastest.




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Old 10-11-2007, 11:28 PM   #4213
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What pinion would a guy run with a lrp tc comp with stock spur for a 7.5 lrp with sintered arm? What is the best spur to get 64 pitch? It has the stock 87 tooth on now.
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Old 10-12-2007, 04:37 AM   #4214
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Got my built TC5 tuesday and raced it wednesday night with stock setup out of box. Track was asphalt car park track. To tell the truth, car wasnt to bad, it was fast as anything and seemed to be stuck to the track, sometimes to much grip. I havent got all the tuning parts yet (springs etc) and want to know wat setup i should use for my asphalt carpark track. Is it normal for the steering to be turned down to 40% on my DX3.0, :/ That was how much steering i needed
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Old 10-12-2007, 06:49 PM   #4215
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the original setup seems not suitable for asphalt, I have tried it but get understeering. At least change the spring to F/blue, R/silver and F/R 40 oil, rear toe in 3degree
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