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Old 11-28-2010, 07:44 PM   #1351
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Jason is the part number for the CH12 damper tube/body mount brace CH1041? Mine got smashed by a touring car at Minnreg this weekend.
That's it, here's a list of replacement parts that one should consider, CH1041 is the first item.
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Old 11-28-2010, 09:01 PM   #1352
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I ran my new CH for the first time today, as always the quality of the product is awesome. It carries alot more speed than my 12R, I need to get the setup more refined for our track but I can see the potential in this car from this one outing. .
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Old 11-29-2010, 12:16 PM   #1353
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Had a decent run Saturday with my CH12FE. Still waiting on the front standoff set and a few other items to come in from Florida. I did notice that this car has a ton of steering with my current setup, which consists of:

Front:
1.8mm carbon flex plates
5* castor
~ .5* toe-out
1.5* negative camber
3.5mm ride height
.5mm droop

Rear:
Gold Spring and 40 wt.
shock mount all the way back
4mm ride height even on chassis and pod
1mm droop
1.5mm flex links in soft position

I started out with 10* castor, Lilac fronts and Yellow rears and the cars was way tail happy. I tried reducing castor to 5* and replacing the Lilacs with black fronts and the car was driveable. Not great, but able to run mid-pack. I then tried Purple fronts and the car was a bulldozer the first 4-5 laps and was then pretty solid until near the end of the race, where it became a bit tail happy again. This resulted in a 3rd place overall finish out of seven. My fast laps were only a couple of tenths off our scorching winner, but the consistency is way off.

What changes should I make from here? As mentioned I have the front standoffs coming. Should I even put these on? Seems the tire combo I ended up with (yellow rear with black or purple fronts), though not what I planned on running, seems to be working okay and I think with a few tweaks I should be able to get the car a bit more dialed. Right now, my car seems to carry more speed through the tightest turns compared to the CRCs and 12R5s. The initial turn in is a bit aggressive and as the fronts gum up, the rear end becomes loose. Should I try pink rears and some other front? Should I soften the rear end? Thinner flex link or...?
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Old 11-29-2010, 12:34 PM   #1354
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How much and what kind of traction compound are you using? I found when using Jack the compound would wick across the tire ending up with a lot more of the tire with compound on it than I wanted and that would result in the car getting tail happy. I ended up doing the inside 1/3rd then taking the wheels off of the car and setting them compound side down to make sure it didn't wick very far or pool up on the low side.
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Old 11-29-2010, 12:47 PM   #1355
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biz77,

In my (admittedly limited) experience with the CH12 NFE I also found it difficult to get the rear planted without resorting to making the front end push until I shimmed up the front stand-offs.

Shimming the upper-arm block seems to be a very powerful tuning adjustment that takes alot of the aggressiveness out of the turn-in. This, in turn, makes it easier to balance the car to get good turn-in and still keep the rear planted. I'm now running 1-2mm (depending on the track) of shims under the upper-arm block (I don't have the extended standoffs yet) with Lilac fronts (sauced inside 1/3) and Yellow rears (sauced fully). The rest of my setup is very much like yours except that I run the 1.2mm carbon rear flex plates in the soft setting which should also help the aggressive turn-in. In addition, I picked up the 2mm spacers that go behind the front axles and found that they also help tame down the turn-in by widening the front track width.

Hope that helps!

Cheers,
Mike
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Old 11-29-2010, 01:32 PM   #1356
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Originally Posted by biz77 View Post
Had a decent run Saturday with my CH12FE. Still waiting on the front standoff set and a few other items to come in from Florida. I did notice that this car has a ton of steering with my current setup, which consists of:

Front:
1.8mm carbon flex plates
5* castor
~ .5* toe-out
1.5* negative camber
3.5mm ride height
.5mm droop

Rear:
Gold Spring and 40 wt.
shock mount all the way back
4mm ride height even on chassis and pod
1mm droop
1.5mm flex links in soft position

I started out with 10* castor, Lilac fronts and Yellow rears and the cars was way tail happy. I tried reducing castor to 5* and replacing the Lilacs with black fronts and the car was driveable. Not great, but able to run mid-pack. I then tried Purple fronts and the car was a bulldozer the first 4-5 laps and was then pretty solid until near the end of the race, where it became a bit tail happy again. This resulted in a 3rd place overall finish out of seven. My fast laps were only a couple of tenths off our scorching winner, but the consistency is way off.

What changes should I make from here? As mentioned I have the front standoffs coming. Should I even put these on? Seems the tire combo I ended up with (yellow rear with black or purple fronts), though not what I planned on running, seems to be working okay and I think with a few tweaks I should be able to get the car a bit more dialed. Right now, my car seems to carry more speed through the tightest turns compared to the CRCs and 12R5s. The initial turn in is a bit aggressive and as the fronts gum up, the rear end becomes loose. Should I try pink rears and some other front? Should I soften the rear end? Thinner flex link or...?
When the car loops towards the end of the run, this is usually from front tires scrubbing. What you can do is go back to a softer front tire, go to maximum caster, but reduce your camber. Camber is a very powerful adjustment for tuning front bite. Less camber will tone the front down and more camber will increase front traction and increase steering. Stay awya from the nitro rubber or natural rubber family in the rear as it makes the car very darty and run notchy. The 1.2mm rear flex plates work really well also. Hope this helps.
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Old 11-29-2010, 01:33 PM   #1357
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How much and what kind of traction compound are you using? I found when using Jack the compound would wick across the tire ending up with a lot more of the tire with compound on it than I wanted and that would result in the car getting tail happy. I ended up doing the inside 1/3rd then taking the wheels off of the car and setting them compound side down to make sure it didn't wick very far or pool up on the low side.
Started with 1/3 JTG inside front on lilacs with full sauce on yellows. Tried no sauce on lilacs and full sauce on yellows. 1/3 sauce on blacks with full sauce on yellows. 1/2 sauce on purple with full sauce on yellow. Finally, 1/3 sauce on inside of purples with full sauce on yellows. The last two scenarios were about the same, except with 1/2 sauce I had a little better bite in the beginning with quite a bit of over steer at the end. The other scenario left me pushing hard at the beginning and oversteering abit less at the end. The last combo was the best of the night. I know the car can be better, but I still think it was already carrying more corner speed than my old 12RR. It just wasn't consistent or predictable. On the plus side, there was very little front tire wear compared to the 12RR.
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Old 11-29-2010, 02:01 PM   #1358
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Thank you Hyper Mike and Jason. I will wait until I get the front standoffs and install those. Go back and start with Lilac/yellow. Looks like I have the 1.2 mm rear links, not the 1.5's as stated, so I will stick with those. From there I will adjust camber, if need be, to tame the steering a bit more. I may also try extending the front track width a bit more. I did not mention that, but currently have a single shim behind each front wheel.

On another note, has anyone broken any carbon parts on thier new front end yet? I saw a bent block, but no reports of broken carbon. I ask because my car took a couple of serious beatings and so far nothing has shown any sign of fatigue.
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Old 11-29-2010, 04:01 PM   #1359
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On another note, has anyone broken any carbon parts on thier new front end yet? I saw a bent block, but no reports of broken carbon. I ask because my car took a couple of serious beatings and so far nothing has shown any sign of fatigue.
Mine has taken some smacks as well, the arms and sub plates are tough as nails.

Only damage so far has been a couple of pivot balls [threads ripped out from the top plate taking the impact load, but thankfully not bending], and a couple flex links.

It's a tough car.
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Old 11-29-2010, 04:41 PM   #1360
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Jason, the 'BIRD' is in flight

Thanks ALOT brah
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Old 11-29-2010, 04:49 PM   #1361
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i dont own one, but ive seen them raced at the track i go to, and i have to add that they are a very tough and competitive car.
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Old 12-01-2010, 06:15 AM   #1362
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What servo savers/arms do you guys use in CH12 with new front end? Which servo position do you run (angled upper or angled lower)? How much ackerman do you use (ball stud position in servo saver)?

I have heard few opinions, that Kimbrough servo savers are unreliable, aren't they?

Thank you.
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Old 12-01-2010, 07:12 AM   #1363
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i have a 9650 kimbrough saver in the middle with c/f brace,angled mounted back position,don't know how much ackerman
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Old 12-01-2010, 08:46 AM   #1364
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I use...

- Graupner DES 676 BB servo
- Kimbrough servo saver (small)
- Ball-studs in middle outer holes
- 0 ackerman shims
- Angled mounts

The Kimbrough servo savers are thé best servo savers there are!!! I have been using them for many years now and never had a problem with them...

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Old 12-01-2010, 08:52 AM   #1365
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The Kimbrough servo savers are thé best servo savers there are!!! I have been using them for many years now and never had a problem with them...
Especially with the BMI DB5305 Carbon Servo Saver Brace.

Do you have your balls on the front or back?
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