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Old 05-31-2007 | 01:14 PM
  #25621  
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hi i wanted to ask you one question can a Futaba S9451 Servo Digital High-Speed/Torque can be installed a calandra 3.1.
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Old 05-31-2007 | 03:20 PM
  #25622  
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Originally Posted by TeamSkitz06
hi i wanted to ask you one question can a Futaba S9451 Servo Digital High-Speed/Torque can be installed a calandra 3.1.
Yes. I can help you with that at the track this week.
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Old 05-31-2007 | 08:25 PM
  #25623  
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Just wondering, i just got a CRC 3.2R, i have a peak vantage 12x2 motor in it at the monment and with a 74 tooth spur i have no idea where to start with the pinion. Its a medium length, tight asphalt track and im running TEAM CRC - TRACK MAGNETS - 12th mntd Pink Rear tires,(Dunno what diametre they are). Thanks all
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Old 05-31-2007 | 09:39 PM
  #25624  
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Unfortunately, no one here has any idea either--the tire diameter is a critical element of the roll-out puzzle.

Do yourself an ENORMOUS favor if you have a Harbor Freight in your village go there and pick up a digital caliper. A 6" caliper is almost always on sale for $16, and if it's not on sale it's a whopping $20. I've found I prefer an 8" ($30, though they're now on sale for $23!!) so I can measure overall widths, but for over 90% of your 1/12 measuring the 6" are just the ticket.

If you don't have a HF in your village you can buy online. Check the calipers

6" caliper at Harbor Freight

8" caliper at Harbor Freight

A caliper is a MUST HAVE tool. THEN you'll always know what your tire diameters are and we'll have to point you to the roll-out chart generators.
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Old 05-31-2007 | 10:04 PM
  #25625  
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Ok ive measured and there 48mm. What is a good rollout/gear ratio for a 12x2 on a crc 3.2r and how do u calculate it (IS there a site)?. Thanks all
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Old 05-31-2007 | 10:24 PM
  #25626  
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Overall tire diameter times pi divided by gear ratio (spur divided by pinion) gives roll out. Your known variables are tire diameter, pi, and spur. We need to decide on a roll-out and choose a pinion.

I've not done any real "brushed" mod racing, preferring to run brushless in mod. I gear my 19T and stock in the mid-high 40's for roll-out, but when I'm trying something new I prefer to be a little conservative and sneak up on the right combo. So let's say 40mm is the desired roll-out, just for argument's sake...if anyone disagrees please speak right up!

So, 48mm diameter times pi (3.14159, or 22/7, your choice) gives a circumference of approx 150.8mm. Now we need to find what one would divide 150.8 by to give 40 (remember that crazy Commutative Property of Multiplication? It works for division too!)...the answer is to divide 150.8 BY 40, which yields 3.77. Similarly, if we divide 74 by 3.77 we get a pinion of 19.62. That .62 tooth plays HELL with spur gear life, so you'll find that 19 teeth is a bit under 40mm rollout and 20 teeth is a bit above.

Now...during your race day you need to monitor the tire diameter. As the diameter decreases you need to increase the pinon tooth count to compensate and hold the rollout at the desired dimension.

Another "hint"...use 64P gears for 1/12. Not only are they more efficient, they'll also give closer gear selections as a tooth either way on, say, a 28-tooth pinion is a much finer increment of adjustment than a tooth either way on a 20-tooth pinion.

hth. Hopefully someone will point to the site(s) that have gearing calculators. I use the Excell-based one Blake posted some time back and have it downloaded to my computer.

Scottrik
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Old 05-31-2007 | 10:27 PM
  #25627  
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gearchart.com has one
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Old 05-31-2007 | 10:32 PM
  #25628  
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Thanks for ur help scotrik and all, ur great help.
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Old 05-31-2007 | 11:13 PM
  #25629  
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Originally Posted by losi guy
It reduces caster at turn in and increases at exit, it can cause tire scrub and slow you down in a turn if not setup right.
Thanks guys, great expaination. So how do I setup reactive castor?
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Old 05-31-2007 | 11:20 PM
  #25630  
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Hi guys,

I am pleased to announce that the 1/12 Carpet Ripper upgrade kits will finally be available within couple of weeks! The kits will be send to those who have pre-ordered right after last parts will arrive.

Due to delay with few items from subcontractors the shipping is late from the date informed earlier (the end of the May). I am sure that the waiting has been worth it

More info including photos of the spare parts and the production version of the kit will be available at the homepage www.v-dezign.net shortly.

If you havent ordered yours yet, you can do it by contacting me by email at [email protected]. Also for pricelist and availability, please email me.

The website has been updated lately, check some new photos and news on the News section and photos from Paintings > Team drivers section.

regards,
Vesa
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Old 06-01-2007 | 03:19 AM
  #25631  
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Originally Posted by Big B
Thanks guys, great expaination. So how do I setup reactive castor?
the thing i found is that the 10 degree blocks work best everywhere.i always start at 2 degrees of static castor and i will increase the static if need be.usually 2 degrees does the trick.if you want more on power steering and less off power you can always add static castor up to 4 degrees to accomodate with shims.
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Old 06-01-2007 | 02:24 PM
  #25632  
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Originally Posted by Big B
Thanks guys, great expaination. So how do I setup reactive castor?
Most run the 10* castor blocks shimed one in front, one in rear. This equals around 4* static castor and 2* reactive. If the car is too hard to drive, try the 5* blocks.
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Old 06-01-2007 | 04:44 PM
  #25633  
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hmm,the only static castor adjustment i see on the AE front end is between 2 and 4 degrees.shims centered is 3 degrees.i dont know what they claim but this is actual measurement.
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Old 06-01-2007 | 07:49 PM
  #25634  
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Originally Posted by protc3
hmm,the only static castor adjustment i see on the AE front end is between 2 and 4 degrees.shims centered is 3 degrees.i dont know what they claim but this is actual measurement.
This from the L3 instructions.....when my shims are centered the actual static castor is 4-4.5*.
Attached Thumbnails 1/12 forum-castor.jpg  
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Old 06-01-2007 | 09:15 PM
  #25635  
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David, I won't be there next saturday to race at HTSA. I will be working, trying to make some extra $$$$. I will catch you some other time. I am not backing out.
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