333LikesXray XB2 2WD Buggy Thread
05-04-2019, 06:44 PM - Wikipost
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07-31-2016, 03:53 PM
#3481
07-31-2016, 04:17 PM
#3482
X-rays new carbon chassis reads it will increase flex and traction. It's 2.5mm. I don't read anything regarding the exotek 2.5 mm carbon increasing traction. Could there be something different about the carbon used? I know Socket's liverc write up indicated it was stiff and that was the benefit. Anyone else have any expereince with this and could it be the weave?
And a flexible carbon chassis was always slower than a stiff carbon chassis.
A stiff carbon chassis provides crisper handling and generally more predictable than a 'flexy' carbon chassis... flexy carbon chassis would tend to 'bounce' on landing doubles and snap loose through rough sections if your line wasn't perfect thus why Exotek spec'd the stiffest weave carbon fiber.
Alloy chassis- low to medium grip tracks= easy to drive.
Carbon chassis- medium to high grip tracks= more responsive.
07-31-2016, 04:31 PM
#3483
The beauty of composites is that you can tailor the layup to achieve the results you want. If you want more bending stiffness, add more plies of uni-direcitonal. More torsional stiffness, add more +/-45.
Lots of good engineering tools available now to perform analysis on composites too. Back in the day we used to have to do a lot of estimating in NASTRAN to get the right properties. Now you can plug in what fabric, how many plies and out comes a beautiful structural model. Frankly I'm shocked that there hasn't been more analytical work in RC cars. Still lots of flat plates of CF cut out with a water jet. I suspect that someday we will have more 3 dimensional composites and things will get very interesting.
Lots of good engineering tools available now to perform analysis on composites too. Back in the day we used to have to do a lot of estimating in NASTRAN to get the right properties. Now you can plug in what fabric, how many plies and out comes a beautiful structural model. Frankly I'm shocked that there hasn't been more analytical work in RC cars. Still lots of flat plates of CF cut out with a water jet. I suspect that someday we will have more 3 dimensional composites and things will get very interesting.
07-31-2016, 06:59 PM
#3485
Tech Fanatic
iTrader: (15)
1. lay the rear shocks down as much as possible
2. adjust camber and camber gain so rear wheels are flat when car is at a full roll in turns
3. run a lower roll center by reducing ball stud height on the rear hubs or increasing the height on the rear roll center block.
4. softer rear suspension
5. more droop in the front to allow the rear to bite harder
6. reduce anti squat to allow the rear to sag a little more and bite harder
7. add some weight to the rear if you're running the CE
07-31-2016, 07:22 PM
#3486
That's the track the extra read droop really benefitted me. I ran on a wet day with holeshots. Was it blue groove today?
I've been debating to try in the front but thought the front had enough droop in comparison to the rear. Are you running limiters in your shocks? Thx
. Thx
I've been debating to try in the front but thought the front had enough droop in comparison to the rear. Are you running limiters in your shocks? Thx
. Thx
Update installed the new XRAY long shock ends on the rear of the XB2. That alone made a big difference car was landing better rear traction was better. I installed them up to flush with the threads on the shock shafts.
Then I also installed them in the front it became a little difficult to get less than 22mm ride him eight. But the car handled even better. This is what was missing on the XB2. By the time I freshened my shocks and got used to the new handling. I shaved 0.5 sec.
Then I also installed them in the front it became a little difficult to get less than 22mm ride him eight. But the car handled even better. This is what was missing on the XB2. By the time I freshened my shocks and got used to the new handling. I shaved 0.5 sec.
07-31-2016, 08:27 PM
#3487
As a temporary solution in my search of more rear droop, I followed the advise you guys gave me and I removed the limiter inside the body itself and went -1 on the shock ends. My droop is now acceptable and I will be testing it at my local LHS/track this week. I'm excited to see the difference.
07-31-2016, 09:42 PM
#3488
With my testing with regard to alloy or carbon- Alloy chassis has always provided more traction/stability on clay than a carbon chassis.
And a flexible carbon chassis was always slower than a stiff carbon chassis.
A stiff carbon chassis provides crisper handling and generally more predictable than a 'flexy' carbon chassis... flexy carbon chassis would tend to 'bounce' on landing doubles and snap loose through rough sections if your line wasn't perfect thus why Exotek spec'd the stiffest weave carbon fiber.
Alloy chassis- low to medium grip tracks= easy to drive.
Carbon chassis- medium to high grip tracks= more responsive.
And a flexible carbon chassis was always slower than a stiff carbon chassis.
A stiff carbon chassis provides crisper handling and generally more predictable than a 'flexy' carbon chassis... flexy carbon chassis would tend to 'bounce' on landing doubles and snap loose through rough sections if your line wasn't perfect thus why Exotek spec'd the stiffest weave carbon fiber.
Alloy chassis- low to medium grip tracks= easy to drive.
Carbon chassis- medium to high grip tracks= more responsive.
I'll stick with "easy to drive" for now, since I'm running a 7.5 and usually at OCRC, which I would classify as medium. But if I ever shift this car to stock, the CF chassis may make sense.
I like exotek parts too. I've found the quality good for several different cars that I've bought parts for.
08-01-2016, 05:36 AM
#3489
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Last edited by Slapjack; 08-01-2016 at 10:26 AM.
08-03-2016, 06:46 PM
#3490
Great info. Thanks.
I'll stick with "easy to drive" for now, since I'm running a 7.5 and usually at OCRC, which I would classify as medium. But if I ever shift this car to stock, the CF chassis may make sense.
I like exotek parts too. I've found the quality good for several different cars that I've bought parts for.
I'll stick with "easy to drive" for now, since I'm running a 7.5 and usually at OCRC, which I would classify as medium. But if I ever shift this car to stock, the CF chassis may make sense.
I like exotek parts too. I've found the quality good for several different cars that I've bought parts for.
08-03-2016, 10:55 PM
#3491
This is a very helpful post and answers a lot of my questions. Thanks for posting this
With my testing with regard to alloy or carbon- Alloy chassis has always provided more traction/stability on clay than a carbon chassis.
And a flexible carbon chassis was always slower than a stiff carbon chassis.
A stiff carbon chassis provides crisper handling and generally more predictable than a 'flexy' carbon chassis... flexy carbon chassis would tend to 'bounce' on landing doubles and snap loose through rough sections if your line wasn't perfect thus why Exotek spec'd the stiffest weave carbon fiber.
Alloy chassis- low to medium grip tracks= easy to drive.
Carbon chassis- medium to high grip tracks= more responsive.
And a flexible carbon chassis was always slower than a stiff carbon chassis.
A stiff carbon chassis provides crisper handling and generally more predictable than a 'flexy' carbon chassis... flexy carbon chassis would tend to 'bounce' on landing doubles and snap loose through rough sections if your line wasn't perfect thus why Exotek spec'd the stiffest weave carbon fiber.
Alloy chassis- low to medium grip tracks= easy to drive.
Carbon chassis- medium to high grip tracks= more responsive.
08-03-2016, 11:20 PM
#3493
Wonder if exotek would ever consider making a 3 gear for the xb2 carpet. I prefer my laydown but always miss the punch of the 3 gear in my de
08-05-2016, 01:37 AM
#3495
Website. Keep in mind it's in AUD so was a nice surprise to see the cost go down. Ended up Sending him an email with what I wanted before I purchased as I had some questions about shipping and customization. He was very responsive. I purchased the carbon rear tower mostly because I liked the look of it. Now that Xray has the 21mm Rod ends I cant imagine needing any more droop.
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