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Old 11-10-2008, 01:23 PM   #166
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I am also very new to the 12th scale scene and i just actually switched to a 78 tooth spur 64 pitch and a 40 tooth pinion for a medium sized track. So far it is working great.
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Old 12-21-2008, 06:33 PM   #167
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I have a question about the gearing for a 13.5, What are you guys running for a spur and pinion. The track is big, with medium traction.
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Old 12-23-2008, 03:49 AM   #168
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Quote:
Originally Posted by beyondthepack View Post
I have a question about the gearing for a 13.5, What are you guys running for a spur and pinion. The track is big, with medium traction.
It is not possible to quote a spur and pinion without knowing the tyre size that is being run. When people first start running in 12th they often have trouble with this, especially if they are moving over from TC/Sedan with rubber tyres. In 12th (and other foam classes) the tyres can be different sizes and this has a great effect on the overall gear ratio. Because of this something called rollout is used to define the actual ratio taking the tyre size into account.

A description and charts for this can be found at http://www.carsrcracing.co.uk/?page_id=33. The charts are done in millimetres per rev though rather than inches.

I've not run a 13.5 myself (UK rules are 10.5), but from what I've heard use a 78 tooth spur and aim for a starting rollout of around 68mmpr.

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Old 12-23-2008, 08:11 AM   #169
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Hot Bodies USA has officially received their shipment of Cyclone 12Xs. They are now shipping to distributers. This is the car that Hara and the rest of the HB team first showcased at the 2008 onroad worlds in Thailand. Here is the list of updated features.

Carbon rear axle
Clamping left rear hub
ATC front T-bar mount (optional)
Lowered front arms with pivot ball adjustment
New steering blocks with 4mm trail
New threaded front axles
Full set of 0.25mm difference rear ride height adjusters
Titanium coated kingpins
Titanium coated front upper arm shafts
Titanium coated shock shaft (same length as before)
FRP front cross brace
Great new packaging

Look and ask for this car at a hobbyshop near you.
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Old 01-05-2009, 06:05 AM   #170
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Anyone fit a KO 949 servo in their C12 using the 1 piece mount? I shimmed it forward 2mm using spacers but wondering how much this will effect steering/ackerman? Looking at some of the pics in here I see people shimming their servo saver forward so maybe it is the same theory. Just curious if anyone has any feedback.
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Old 01-05-2009, 08:17 AM   #171
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I am trying to track down soft,medium and hard springs for the cyclone 12 front end..I cant seem to find them anywhere in stock.

Any suggestions?

Jamie
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Old 01-05-2009, 09:10 AM   #172
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Quote:
Originally Posted by Anemic_SluG View Post
Anyone fit a KO 949 servo in their C12 using the 1 piece mount? I shimmed it forward 2mm using spacers but wondering how much this will effect steering/ackerman? Looking at some of the pics in here I see people shimming their servo saver forward so maybe it is the same theory. Just curious if anyone has any feedback.
Not used the alloy mount, but moving the servo forwards does affect ackerman. The optimal servo saver shimming (i.e. maximum ackerman) using standard mount and servo saver for a Futaba S9650 is 2.5mm. Any more and it starts losing it again. Hard to say for other servos due to size differences, but it sounds like moving it 2mm forwards will actually make it better rather than worse, though trying it out is always the best test.

If 12X arms are used it isn't possible to move forwards quite as much, or the turnbuckles will catch. Again for a 9650 1.5-2mm is the max.

Trev
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Old 01-05-2009, 09:19 AM   #173
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Quote:
Originally Posted by senna555 View Post
I am trying to track down soft,medium and hard springs for the cyclone 12 front end..I cant seem to find them anywhere in stock.

Any suggestions?

Jamie
Probably not the answer you want but they appear to be in short supply in the UK as well. That may be because just about everyone I know uses Associated springs on the front (they fit fine but are slightly longer than the HB ones), so there is not much call for them over here. I don't think my kit HB ones have even been on the car!

Trev
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Old 01-05-2009, 09:33 AM   #174
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I kinda figured that was the going to be the answer.

I tried different springs but I honestly like the hb ones the best and wanted the other rates to test.

What springs have you been using .18 and .20?
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Old 01-05-2009, 10:38 AM   #175
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many Cyclone 12 now !
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Old 01-06-2009, 02:16 AM   #176
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Quote:
Originally Posted by senna555 View Post
I kinda figured that was the going to be the answer.

I tried different springs but I honestly like the hb ones the best and wanted the other rates to test.

What springs have you been using .18 and .20?
We've been almost exclusively using .020 springs in the UK, that's on carpet, we don't run asphalt.

I've been told that the HB hard spring is just slightly softer than an .020 Associated, so that could be a starting point for comparison.

Trev
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Old 01-06-2009, 07:00 AM   #177
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Quote:
Originally Posted by TrevCoult View Post
Not used the alloy mount, but moving the servo forwards does affect ackerman. The optimal servo saver shimming (i.e. maximum ackerman) using standard mount and servo saver for a Futaba S9650 is 2.5mm. Any more and it starts losing it again. Hard to say for other servos due to size differences, but it sounds like moving it 2mm forwards will actually make it better rather than worse, though trying it out is always the best test.

If 12X arms are used it isn't possible to move forwards quite as much, or the turnbuckles will catch. Again for a 9650 1.5-2mm is the max.

Trev
Once I got it all together seems like it worked just fine with the 2mm spacers. It puts the steering rods right in the valley on the arm and doesn't bind. Will post some pics later after I finish the wireing. So far looks like a great car.
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Old 01-06-2009, 08:01 AM   #178
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Quote:
Originally Posted by beyondthepack View Post
I'm looking for a roll-out on a 13.5, any suggestions?
Quote:
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I have a question about the gearing for a 13.5, What are you guys running for a spur and pinion. The track is big, with medium traction.
Most of the guys around here are running 60-65mm rollout on a 4 cell 13.5 car. I start a set of tires at 44.5mm in the back, so for me, 37/84 would get me in the ballpark and shouldn't be an issue fitting in the pod. 39/88 would get me there, but I might start getting close to running out of room at the front of the pod. Maybe go a tooth or two down on the pinion for the first run and keep an eye on temps, then go up looking for better lap times until the lap times stop getting better, or the motor starts looking hot... Temperature probably won't be an issue on a big medium grip track, but better safe than sorry...
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Old 02-17-2009, 12:32 AM   #179
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Default twitchy subject

Hello,
I have both the C12 and the C12X. I have been running 1/12th scale for a few years now. I know that 1/12th scale cars tend to be very twitchy. Both the cars are built pretty much stock. The car runs great but I think I can drive the car alot hard if I can figure out a way to take some of the twitchy out. I read that the front brace is supposed to give the car more steering. Is that true? I thought it would be the opposite. I have dialed the dual rate in my radial down to almost 50%. That has been the only way I am able to drive the car. I am very happy with both cars just looking for a little more. Any suggestions or help would be appreciated. THX!
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Old 02-17-2009, 01:10 AM   #180
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Hello,
I have both the C12 and the C12X. I have been running 1/12th scale for a few years now. I know that 1/12th scale cars tend to be very twitchy. Both the cars are built pretty much stock. The car runs great but I think I can drive the car alot hard if I can figure out a way to take some of the twitchy out. I read that the front brace is supposed to give the car more steering. Is that true? I thought it would be the opposite. I have dialed the dual rate in my radial down to almost 50%. That has been the only way I am able to drive the car. I am very happy with both cars just looking for a little more. Any suggestions or help would be appreciated. THX!
The front brace should smooth out the car. There are many things that you can do to calm the steering down....run a little negative steering expo on your radio, most run -5-10%. Widen the front end with shims, harder front tire, harder front spring, less tire sauce on front tires, higher front ride height than rear, softer rear dampening.....the list goes on......

Tire selection is usually the first thing to figure out, see what others are running. Your dual rate at 50% is fine, sometimes you have to make chages to the rear in order to affect the front.
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