Best new(er) chassis for flex

track in located in the high desert ( Wheel2Wheel Raceway, Victorville CA). I'd call in more of a sandy clay than anything. It's set up for speedway bikes and stay tacky/wet all night. My driver is 80lbs and the kart enters well, but seems to come off the corners loose, like it lacks forward bite, grip or side bite in the RR. It seems lazy in transfering the LS to the RS, or doesn't at all. Seat is mounted hight and toward the engine best I can. Cross is anywhere between 52-57%, left side is 53% and nose is 47%. We are running a Duro treaded tire, punches around 50-60 depending on the temp/sun. No prep allowed. you can youtube it for an idea of conditions, size,etc..

I agree, I would typically hesitate to go to a newer chassis, but think there are few options that are soft enough. Alot of guys run the older, mid steel chassis or euro that flexes more, but personally I want something I can run all over the west coast and be competitive as well.
I'd get off that tire to start. What is the tire rule there?
 
I appreciate everyone's opinion on what track I run, or tire, etc... but it's their rules and the only track within 3 hrs of me, so it is what it is. My original question still stands. Thanks for those who provided meaningful input.
 
I appreciate everyone's opinion on what track I run, or tire, etc... but it's their rules and the only track within 3 hrs of me, so it is what it is. My original question still stands. Thanks for those who provided meaningful input.
I am asking do you have to run the duro tire or can you run a burris or hoosier is there a duro rule?
 
I appreciate everyone's opinion on what track I run, or tire, etc... but it's their rules and the only track within 3 hrs of me, so it is what it is. My original question still stands. Thanks for those who provided meaningful input.

Tires:​

  • Front: D1-4007-1/D1-4007s-1 11-5.50×6
  • Left/Right Rear D1-4008-1/D1-4008s 12-9.00×6
  • May run 11-5.50 x 6 on all four corners
  • Grooving must follow existing pattern, no cross groves, max width 5/32
  • Air stems must face out

212 Engine Spec:​

  • Motor as supplied, no modifications at all, if seals are broken, motor cannot be used in competition. Do not add anything for performance, mud shield only
  • Standard max torque clutch cannot alter in anyway, drill lightened, etc
  • Engine 10 tooth rear as noted per track, W2W is 47, 49, or 50
  • Spark plug BPR6ES may be used
  • Headpipe as supplied
  • No jack shaft
  • RPM and tack okay
  • Fixed gear ratios as follows:
*at W2W 10 eng, 47/49/50 for rear, all other gear ratios at other tracks will be determined prior to race by W2W
So with these tire, and gear rules it's gonna play a big part in the set up of any offset kart. Having to run skinny's on both fronts is problematic for must of these karts that were not designed to be run like this. Taking that into consideration I would go with a QRC cage kart and take the cage off and run it as a flat kart. Alot of guys are running these karts at Hanford, Chowchilla, Hillsferry and having great success. I'd look for a .083 open frame and go from there. We have one racing out of our camp and has won everywhere we have gone. I know a few guys on Legends that run the two front skinnys and they seem to work as well. As do the old Invader straight rails, especially in the low horsepower classes.
 
Does anyone have any pictures or video that show chassis’s flexing. What does the movement look like? Where are the bends etc?
 
Does anyone have any pictures or video that show chassis’s flexing. What does the movement look like? Where are the bends etc?
I'm afraid you'll be very hard pressed to find anything like that. There are few people in the country that have a Chassis Dyno, and the few that do aren't going to let that info out.

On track video of a chassis moving does very little for analysis.
 
I'm afraid you'll be very hard pressed to find anything like that. There are few people in the country that have a Chassis Dyno, and the few that do aren't going to let that info out.

On track video of a chassis moving does very little for analysis.
I’ve never driven one of these things. Just wondering how the flex occurs.

I think I could better understand the big picture better if I understood everything LR tire
 
I’ve never driven one of these things. Just wondering how the flex occurs.

I think I could better understand the big picture better if I understood everything LR tire
Most can't feel the flex no matter how little or how much there is. The biggest sensation is the load rolling up on the rf corner/lack there of and then releasing. Depending on chassis brand/make this is either a lot, a little, or some middle ground depending on the track surface. On a high bite track you'd feel this on almost any kart. On a low bite track some you'll feel, others you won't at all. The LR corner will be flexing the most, just push down on the tail on the grid and you'll see most chassis' give and sag, with the opposite when the driver is in the seat due to the weight being in front of the bend on the lr. Add that to the rolling up on the right front feeling and releasing and that axis on the kart will be most of what someone will be able to describe. Most people when they go from one chassis to another will describe how RF positive it is or isn't compared to the other.

In PRC's release video for the deuce they showed a graphic modeling of the chassis flexing. Similar idea for almost every kart to a varying degree. The waist and lr are doing most/all of the flexing. The rest is just the feeling of load being transferred to a tire and back.
 
Most can't feel the flex no matter how little or how much there is. The biggest sensation is the load rolling up on the rf corner/lack there of and then releasing. Depending on chassis brand/make this is either a lot, a little, or some middle ground depending on the track surface. On a high bite track you'd feel this on almost any kart. On a low bite track some you'll feel, others you won't at all. The LR corner will be flexing the most, just push down on the tail on the grid and you'll see most chassis' give and sag, with the opposite when the driver is in the seat due to the weight being in front of the bend on the lr. Add that to the rolling up on the right front feeling and releasing and that axis on the kart will be most of what someone will be able to describe. Most people when they go from one chassis to another will describe how RF positive it is or isn't compared to the other.

In PRC's release video for the deuce they showed a graphic modeling of the chassis flexing. Similar idea for almost every kart to a varying degree. The waist and lr are doing most/all of the flexing. The rest is just the feeling of load being transferred to a tire and back.
How much flex does the axle control? I assume the thin wall axles allow more flex while the thick ones prevent it.
 
IMO if you have a tire rule and the track always lacks grip, I would start playing with air pressure and adding weight. Since you can't make bite in the tires with prep, you must make mechanical bite in the chassis. With a smaller driver you do that by adding weight to exaggerate the characteristics of the chassis and make the tires work harder. A lot of juniors are too small to transfer the weight on their own on a slick track and being 10-25lbs over will not hurt if it solves your problem.
 
I appreciate everyone's opinion on what track I run, or tire, etc... but it's their rules and the only track within 3 hrs of me, so it is what it is. My original question still stands. Thanks for those who provided meaningful input.
You should make the haul up to Chowchilla Jan 14&15 and Jan 28&29 great track lots of competition and great kart counts they've had 16 jr's at most races this season. There's been a bunch of guys coming up from down south and they all love it, it's worth the trip.
 
track in located in the high desert ( Wheel2Wheel Raceway, Victorville CA). I'd call in more of a sandy clay than anything. It's set up for speedway bikes and stay tacky/wet all night. My driver is 80lbs and the kart enters well, but seems to come off the corners loose, like it lacks forward bite, grip or side bite in the RR. It seems lazy in transfering the LS to the RS, or doesn't at all. Seat is mounted hight and toward the engine best I can. Cross is anywhere between 52-57%, left side is 53% and nose is 47%. We are running a Duro treaded tire, punches around 50-60 depending on the temp/sun. No prep allowed. you can youtube it for an idea of conditions, size,etc..

I agree, I would typically hesitate to go to a newer chassis, but think there are few options that are soft enough. Alot of guys run the older, mid steel chassis or euro that flexes more, but personally I want something I can run all over the west coast and be competitive as well.
I ran that track years ago with a Millenium Tempest with the Socal Oval guys. If they are still prepping the track like they used to, a soft chassis is not going to work, but setting the kart up with more cross and a bit more left weight is going to help you. Later into the evening I would run higher air pressure and also start pulling the LR hub in/out and experiment with the chassis. With those treaded tires, air pressure will be your friend. That track does bite up, a lot and found turning a bit more rpm into the corner will help you as well on exit. Start there and let me know, that track was super fun when I ran it. Another area might be driver and their entry/ exit. I assume you are loose coming out of turn 4, as 1/2 was pretty mellow.
 
You should make the haul up to Chowchilla Jan 14&15 and Jan 28&29 great track lots of competition and great kart counts they've had 16 jr's at most races this season. There's been a bunch of guys coming up from down south and they all love it, it's worth the trip.
We have Chowchilla on our radar, unfortunately the weekends just didn't line up for us this winter, but we will get up there!
 
We mostly run on a very wet/heavy 1/6th dirt track (we go through tearoffs) and looking for something that can transfer weight well. Driver is 85 lbs and current kart (06 Phenom) just doesn't seem to work well enough. Opinions on new or newer chassis out there that work well in this condition? Was leaning towards a thin tube Scythe.

Thanks, Matt
Didn’t read the whole thread. Any modern kart you can get support for should “flex well.” If you’re looking for bite I would consider increasing caster to transfer more weight to the RF. You’ll need to adjust caster on both sides to maintain an appropriate split. Also be sure the kart is “free” and can flex appropriately. Nerf bars and bumps should move up and down with your hand with minimal force. Bolts attaching the seat to the seat struts should be sure but not over tightened. Motor mount should be positioned at least 2-3 finger widths in front of where the cross rail weld is on right side of the chassis. Chain should have ~1in if play.
 
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