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Old 01-24-2010, 09:27 AM   #106
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Did you soften the suspension when adding the sway bars?
Did you go with a 'quicker' or 'slower' ackermen setting?
How much did you widen the car?
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Old 01-25-2010, 10:55 PM   #107
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Originally Posted by Spdjunky View Post
Did you soften the suspension when adding the sway bars?
Did you go with a 'quicker' or 'slower' ackermen setting?
How much did you widen the car?

Slower ackermen
2.8-2.4 springs
.075 each side front only
kit sway bars
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Old 01-30-2010, 07:07 PM   #108
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Glue is inconsistent. Going to try the ackermen setting.
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Old 02-01-2010, 07:35 AM   #109
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Returning to this topic...

Anyone have any thoughts about the new lower weight limits, and whether they are increasing traction roll?

Here in the UK we are down to 1350gm.

I can honestly say that I never had a traction roll in 8 years of NiMH/1500gm touring car racing. Running all sorts of chassis, all sorts of motors, and all sorts of rubber and foam tyres.

At 1350gm/LiPo I've tried a fair few car setups, even tried switching back to my old car, and the rolling is still happening. At a club meeting last week I was lifting wheels in the first round and flipping at the start of the second. It would have been comical if it wasn't so frustrating!

I'm fairly sure the issue is either the lower weight (which needs a big change in setup that I haven't worked out yet), or the RP30 tyres (which were fine when new at 1500gm but which may have degraded and become a liability - the current set probably has 40-50 runs on them).
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Old 02-01-2010, 08:08 AM   #110
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i wonder that a bit. My issue alittle different, traction rolling didn't start till we ran the track in reverse direction. I am curious if the heavy electronics side could be part of the issue too. Need to find a way to check weight balance but don't have a scale setup.

This week I plan to modify my setup by going a bit softer all around on both cars. Will leave sway bars connected on one, and removed on the other since they cars are the same, only difference being motor brand but same wind.
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Old 02-01-2010, 11:21 AM   #111
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i wonder that a bit. My issue alittle different, traction rolling didn't start till we ran the track in reverse direction. I am curious if the heavy electronics side could be part of the issue too. Need to find a way to check weight balance but don't have a scale setup.

This week I plan to modify my setup by going a bit softer all around on both cars. Will leave sway bars connected on one, and removed on the other since they cars are the same, only difference being motor brand but same wind.
I found softer springs helped, but never got around to trying anything other than kit springs.

Make sure you post your findings afterwards.

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Old 02-01-2010, 12:24 PM   #112
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In VTA racing, I've always struggled with traction rolling as traction has increased in the racing groove.

This past weekend, my TC3 was starting to bicycle a bit. I only changed to a heavier spring rate on the front shocks (moved from blue to gold) and that solved my specific issue. I continued to apply traction compound the same way (3/4 front tire, full rear) and the spring change was enough to allow me to drive hard in the main and take the win.
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Old 02-01-2010, 01:22 PM   #113
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In VTA racing, I've always struggled with traction rolling as traction has increased in the racing groove.

This past weekend, my TC3 was starting to bicycle a bit. I only changed to a heavier spring rate on the front shocks (moved from blue to gold) and that solved my specific issue. I continued to apply traction compound the same way (3/4 front tire, full rear) and the spring change was enough to allow me to drive hard in the main and take the win.
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Old 02-01-2010, 02:57 PM   #114
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I'm just coming back after a long time away, but I wanted to ask a question. When I was racing TC, if I had the car set up exactly to where I loved it, except for having traction roll issues, the first thing I'd start to do is reduce how much of the width of the front tires I'd use compound on. IIRC this was enough to fix any issues pretty much every time.

Is this not a common solution? Or, is this what you guys would consider a 'hack' solution when a setup change is really called for?

Oh, and speaking of that, I remember this if it helps: I would start out by compounding only the outside half. If that was too much, I'd switch it up and compound 80-85% of the tire, but leave the outside dry. That generally did it. This is a long time ago (10 years) so I'm sure things are different now...
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Old 02-01-2010, 04:05 PM   #115
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I'm just coming back after a long time away, but I wanted to ask a question. When I was racing TC, if I had the car set up exactly to where I loved it, except for having traction roll issues, the first thing I'd start to do is reduce how much of the width of the front tires I'd use compound on. IIRC this was enough to fix any issues pretty much every time.

Is this not a common solution? Or, is this what you guys would consider a 'hack' solution when a setup change is really called for?

Oh, and speaking of that, I remember this if it helps: I would start out by compounding only the outside half. If that was too much, I'd switch it up and compound 80-85% of the tire, but leave the outside dry. That generally did it. This is a long time ago (10 years) so I'm sure things are different now...
Depending on the tyres, I've found reducing the additive can compromise the handling over the first few laps, perhaps applyingh to the rear for a lot longer would help, I would not normally apply it to less than half of the front tyres.

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Old 02-01-2010, 04:20 PM   #116
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I was having huge traction roll issues last week. Turned out to be because I switched a used LiPo with no weights, so the car was too light, and that would also probably make it rear-heavy. So there just wasn't enough weight to keep the front end flat when entering corners and cranking the wheel (that's my n00b style, I enter hot and scrub speed by turning).

I'm curious if just moving weight forward would help with corner entry traction roll.

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Old 02-01-2010, 06:15 PM   #117
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Originally Posted by grippgoat View Post
I was having huge traction roll issues last week. Turned out to be because I switched a used LiPo with no weights, so the car was too light, and that would also probably make it rear-heavy. So there just wasn't enough weight to keep the front end flat when entering corners and cranking the wheel (that's my n00b style, I enter hot and scrub speed by turning).

I'm curious if just moving weight forward would help with corner entry traction roll.

-Mike
I found that moving weight forward on my chassis helped the rear end rotate more, but not dig in as much on corner entry. When trying to cure traction roll you first need to figure out which end of the car is biting too hard.

Also, keep in mind that no amount of tuning you do will fix the problem if your car is out of balance right to left.

First thing I would try after determining what end of the car is having the issue is going wider on the track width. This adjustment has cured most cases of traction roll for me, and seems to be one of the main causes. Next, I would reduce camber change in the "problem" end of the car. This can be done by shortening the upper link.

Both of these changes can cure traction roll without changing the feel of your car under roll a whole lot.

This post is purely based on what I've found to work, and it won't necessarily work for your car, or your track.
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Old 02-22-2010, 09:40 AM   #118
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First question: Does Rear Toe in affect traction rolling at all? How does going from say 3 degrees to 2 degrees or the other way around work in this regard?

Finally got to do some running guys and work on the traction rolling issue.

So to start I figured I would leave my setup on from before so I could get an idea of how things were going. The track this time initially was a bit lower on traction, so no issues there.

Once the traction came up however, the rolling began. I removed the sway bars, this cut out the chattering I was setting of the wheels, but rolls were still there.

So I decided to try going with a softer spring setup, which I did, keeping everything else the same. This time it had too much roll and would end over even easier even on slow turns. So the softer springs were not the ticket. wayy too much body roll.

I then went with a setup that the former team manager ran with the car (except running 3 degree to in instead of 2 degree) and the traction rolling was back to what I was seeing before, albeit, not as much. Car drove well though other than this.

I read some more in that Xray setup book you can download for free, and started looking at the section about roll center. from what I can tell, it appears the way I was going about my linkages was a bit wrong. I started to change the roll center by making it higher, from what the book was saying front and rear.

The vehicle finally started to come around, instead of a guarenteed roll in the turns, it actually seemed to just hug the corner then turn. I am still getting some wheel lift, however, this wheel lift previously would roll the car.

So as it sits, what I am thinking I need is a bit more "drift" I am thinking versus the bite I am having right now. Maybe stiffer springs in the rear. I am thinking the roll now is starting in the rear versus front when mid corner.
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Old 02-22-2010, 10:00 AM   #119
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Of course, in the 1500g, to the 1350g weight drop senario, if you are very desperate to regain control of your car purely as a last resort, make the weight up around the cell area to help.

Depending on the competition though, it may slow you up.
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Old 02-22-2010, 10:22 AM   #120
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Another important thought on traction rolling... tyres.

A change of tyres before my last race meeting cured the traction roll completely. My suspicion is that the worn (and repeatedly additived) rubber had a softened sidewall, which was causing most of the problems.
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