DFW Metro Man

[Russell ATV]

Hello, My name is Russ Barrow. I have been a karting man since I was 12 (Carter Brothers Kart my parents bought me for Christmas) and it never really left my system.

I have been messing around with Combat Robots for the last few years, but have come back to the joy of building and riding.

I have an idea that I am prototyping, and a marketing plan for a business that I am executing. The idea is based on accessible, lightwight, performance vehciles, and it all starts with what I think I know best, Karting.

Stay tuned.......

Russ Barrow
Russell ATV

 

[ed1380]

welcome.
looks like we got us another smart russ.
got any pics of the performance vehicles you're talking about?

 

[RobertD]

welcome to the site! we love pics!

 

[Russell ATV]

Is there anyway in this forum to attach pics, or does everyone go to their web based hosting service of choice? I have not used Flicker or other sites in a while. What would be quick and easy?

The idea I am referencing is based on a flat spring steel suspension. It has taken me several months to determine the right material, thickness, length and design, but I think I have it now. So now I am working through what makes the most stable, compact, comfortable, rugged, and mass produceable product.

The last item is the most difficult. I have been looking for a good 2 stroke for a while, but nothing has really worked out. The 4 stroke Clone engines are great for power and cost, but are a bit heavy for what I am doing.

Russ Barrow
Russell ATV

 

[ed1380]

instead of using "quick reply" hit "go advanced" and then scroll down a bit. there will be a button to manage attachments

 

[Russell ATV]

Thanks, that is what I need. Please keep in mind these are early versions that represent test mules only. I can typically build a new frame a week, resuing the important bits, improving the design dynamics, so i do not waste time making it pretty. I will also be recieving my first shipments from China that will address Seats, wheels, and other bits.

I have changed the suspension since these to a two parallel spring arrangement that makes the design simplier and allows for a thinner, lighter solution.

The Tadpole Quad is an idea that uses the minimal weight solution for a 4 wheel kart. It also makes the design compact and eases steering effort with a solid axle arrangement. Total weight is 85lbs.

The light cart uses a light (11lbs) Tecuseh 4HP two stroke. It was my first test kart, and only drove the one rear wheel. Solid axles are the way to go as this thing pulled right all the time. It weighed only 50lbs. Without a source for a reasonable priced/power 2 stroke, looks like I am stuck with heavier 4 strokes.

Russ Barrow
Russell ATV

 

[ed1380]

im sure you're already though of this, but how about the lifan 2 strokes. 110cc is more than enough and with 4or 5 gears it will scoot

 

[jr dragster T]

Your kart's in those pictures dont look too safe....

 

[Russell ATV]

im sure you're already though of this, but how about the lifan 2 strokes. 110cc is more than enough and with 4or 5 gears it will scoot

I have not seen any 2 strokes from Lifan. Lots of 4 strokes from 50cc to 250cc, but even the small ones start around 50lbs, and have very little power.

Do you have a website link?

Russ Barrow
Russell ATV

 

[Russell ATV]

Your kart's in those pictures dont look too safe....

I am curious to what you consider unsafe. I have addressed a few weaknesses as mentioned earlier, but what do you think you see.

A role cage may seem obvious, but when designing for compactness and weight, the best I can provide is a seat hoop. Also, it is important to note, they do not make 4 Wheelers with role cages, and they weigh on average around 400lbs. In some ways, I think the Buggies that have set out to replace go karts, have caused as many problems as they have solved.

Russ Barrow
Russell ATV

 

[jr dragster T]

Frame looks so narrow and all the small nuts and bolts holding on the front end.

 

[jr dragster T]

And plus your crimped bend's

 

[Russell ATV]

Frame looks so narrow and all the small nuts and bolts holding on the front end.

Through my tests, I was noticing the 1/4 bolts bending. Never had a failure, but I have since moved to 5/16 grade 8. As for how narrow the frame is, not sure how safety is affected there.

As for the crimped bends, all my proto work is done with extremely low cost 1" electrical conduit. Very sturdy stuff, but does not bend or weld like chromoly. I am also using a simple HF pnematic bender, which is not very clean. Once I have honed in on the right design mechanics, I will start spending more than $10 on Frame material.

Russ Barrow
Russell ATV

 

[minibugger]

Wish you well on your venture. Was curious about welding or drilling thru the the spring steel. Assuming that it is spring steel, would it be better to use shackles instead of drilling two holes per side which may be creating an unwanted stress point?

 

[BradenM]

im sure you're already though of this, but how about the lifan 2 strokes. 110cc is more than enough and with 4or 5 gears it will scoot

Russ,
If you can find a local Exhaust shop that will work with you, I would ask them to help you design an expansion chamber that would be suited to this motor, pay them for the blueprints, and fabricate them out of sheet metal. Of course, the first few will be a pain in the bum to fabricate; but once you get the hang of it you can offer it as an option for your high performance mods, in you would have those kinds of options. I'm not sure what you know about expansion chambers, but check them out here, for the animated gif and here.

Best of luck,
Braden.

 

[Russell ATV]

Wish you well on your venture. Was curious about welding or drilling thru the the spring steel. Assuming that it is spring steel, would it be better to use shackles instead of drilling two holes per side which may be creating an unwanted stress point?

Spring steel it is. The beauty of spring steel is it's resiliency. I am using a grade that is more prown to deforming than breaking. The new disign I have uses two parallel spring steel bars, and so far, it is holding up well. The key is to allow enough length for the spring to flex without violating its spring constant. This is also a reason why the frame is narrow.

Drilling it is a pain to the @ss, but I have had good success with Cobalt drill bits. In production, I will likely use a water jet to reduce stress and heat affected zones. No welding though

Russ Barrow
Russell ATV

 

[Russell ATV]

As for the 2 strokes, I am all ears, but I have not found any company selling 2 strokes at a reasonable price (sorry, racing engines are not reasonably priced).

If anyone has a source, please list as I am very interested. I have looked into an expansion chamber, but the math and theory are intense. The best idea would be to reverse engineer something close and then tune from there.

At present using a slightly modified clone 4 stroke engine, I should be able to get power to weight ratios close to a 15-20HP buggy design.

Russ Barrow
Russell ATV

 

[Russell ATV]

Also, please keep the post coming. Part of designing a product is to take the feedback of prospective buyers/active hobbiest. I have thought through a few issues, but may have missed others.

By mid January, I should have a design that merges some of my design elements with production worthy parts (brakes, wheels, seats, steering wheel, etc). I will likely post additional pictures at that time.


Russ Barrow
Russell ATV

 

[BradenM]

Before Expansion chamber's came along, people used to tune straight lengths of pipe, which created a negative pressure wave. It basically helped to suck out the gases from the cylinder. THEN they started adding cones and bouncing sound waves and gases back into the cylinder.
As ed1280 said, get the lifan, and If not an expansion chamber, tune the length of pipe for the RPM that the motor will (generally) be used at for the target market (some being tuned for off-road use, others for pavement, e.t.c.).

Check this out: http://www.motorcycle.com/how-to/ho...ambers-work-and-why-you-should-care-3423.html
Braden.

 

[Kenny_McCormic]

Sled engines are CHEAP.