4 Cycle Four Stroke chassis construction

4stroke
briggs206

(TJ Koyen) #21

Ayyyyy there it is! Guess they didn’t throw it out.


(James McMahon) #22

This will sound contrarian but the soft" vs “stiff” thing is almost pointless. It’s wayyyyy subjective because it’s a combination of the metal, frame construction (narrow waist vs wide, rear bar position) and tubing diameters… But its never actually been measured in any way that I’ve seen shared.

Not to mention that any stiffness is present is not linear and the curve deflection/'force curve will (probably) vary from frame to frame.

Oh and we bolt a bunch of stuff onto the frame and put an organic damper in the seat.

Would be very interested to have a test methodology for chassis “stiffness”, but then you also get into static vs dynamic loads…


(Rob Kozakowski) #23

I’d say that there are 3 categories of chassis used for Briggs racing in the USA…

  1. “CIK” chassis - mostly Euro-made and homologated for international 2-cycle racing.

  2. “WKA” 4-cycle chassis - American-made and designed for the WKA 4-cycle rules.

  3. “ASN Canada” 4-cycle chassis - non-homologated Euro-made chassis, designed for the Canadian 4-cycle rules.

The 2nd and 3rd categories are built to work to specific rules, and (since they are designed for it) arguably work better than other chassis within their respective regulations.

But when it comes to running a Briggs with “typical 2-cycle chassis rules”, all 3 types of chassis seem to be able to work, where they all have some advantages and disadvantages.


(James McMahon) #24

Can you talk a little more about this set of rules? Is the difference just in the lack of homologation with CIK\FIA or are there different dimensions specified in this ruleset also?


(John Kwong) #25

In partial response to Rob K’s post about ASN Canada 4-cycle chassis: We have been using the MOJO D2 4.5/7.1 tires for the last 4 years and many different chassis brands and vintages including pre2003 box pod karts have been successful.

My personal ride has been a 2004 Parolin DC-One that I have won many races and several club championships with. It was a former Rotax chassis but has been very competitive at the two Alberta tracks and in differing weather temps/conditions. It seems now with the popularity and seriousness of LO206 competition that the more specialized built for 4 cycle class chassis are now being manufactured just for LO206 racing but I think it still comes down to track time and tuning to be a contender.

Finding speed and consistency in the Briggs class is a very subtle thing and little things gained from experience and testing are where the speed is found. I think initially racers who race faster classes and new people to the sport look at Briggs as too easy but the closeness of the racing and the consistency needed to win are at a pretty high level


(David Kalb) #26

Tires and track conditions can effect things greatly and make some karts better than others on certain days.

The Arrow AX9 has dominated the WKA Gold Cup on Bridgestone tires. Gary Lawson popularized this kart years ago and was almost unbeatable. He is also the all time winnest driver at the Rock Island Grand Prix. My son has been unbeatable on this kart winning two WKA championships this year and the Winter Cup Jr LO206.

This kart has a great deal of flex and we used a very soft 40m axle. The kart would not actually lift that much but stay very planted and with the torque of the Animal would have great drive off out if the corners. It would almost look like a sling shot. It was especially good on high grip tracks and would run lap after lap without tightening up like most karts.

Only problem is that they haven’t made it in years. Comet basically copied the kart the best they could. MGM and Ionic are doing the same. Coyote also adjusted to make it similar.

There Is a new kart builder, Keener Kart, you are going to want to check out. Running there first ever race at Daytona Man Cup today. Looking at the times Eric Fagan is leading the practices times today on it.

We have run Margay, Coyote, and also did a great deal of testing with a Tony Kart and an Lo206!this year. Our Arrow was still the best.


(John Kwong) #27

That is good to hear about the Arrow AX9 chassis. I just picked one of these up that some Dad had bought brand new for his kid 8 years ago and never drove it. I look forward to finding the limits of this chassis in 2017.


(David Kalb) #28

We ran with 40m soft axle. If you have questions let me know. I am on FB.


(Aaron Hachmeister) #29

So this kinda turned into a discussion of various designs and theories, so I have something for you guys to look at. CRG has a unique frame sitting outside their trailer out here in Vegas, I was wondering what you guys thought of it.


(Nik Goodfellow) #30

Interesting!

They’ve done something like the Kart Repubic KR3 (which I don’t think anyone has seen yet) and looped the front of the chassis round to one tube.

Is that for LO206?


(Aaron Hachmeister) #31

I don’t know what it’s for. There wasn’t an engine on it, just display of the frame. They did however have a radiator on it, so maybe a new TaG design?

The Kart Republics did so well, although having the OK World Champion and WSK Vice-Champ certainly doesn’t hurt anything. It’s a shame they both ran into some crap luck this year. Keirle hit a wall while leading Heat 2, and everyone knows Travisanutto got called for an improper start. They killed it in terms of pace, definitely a good showing


(Bobby Zilliox) #32

What was the outcome over the different chassis? Over the last couple of years what have you discovered what works best?


(roy brewer) #33

if you’re looking for a chassis for the lo206 package, look at VLR karts pretty sure about the cheapest kart but man has their been many wins at high level events including nationals