“4-Cycle or 2-Cycle TaG?”
It’s a question we get a lot. The NHKA Racing Series class structure offers options with both types of engine for racers of every age. No matter which path you choose, you could potentially race the very same engine from childhood through adulthood just by changing a few parts. But let’s start with the question most people are too embarrassed to ask…
“What the Heck Does 2- or 4-Cycle Even Mean?” The “2” and “4” refer to the number of piston movements (up or down) in a complete combustion/exhaust cycle. A 4-cycle engine’s piston (1) goes up in the cylinder to compress the air/fuel mixture, (2) then it is forced back down when the mixture combusts/explodes which is the power stroke. Then the piston, carried by the force of that explosion, (3) goes back up the cylinder to push out the exhaust, and continues to ride that momentum back down to (4) draw in air/fuel mixture for the next cycle. With a 2-cycle, (1) the piston goes up to compress the air/fuel mixture just like in a 4-cycle, but when the combustion/explosion forces the piston back down in the power stroke, the piston generates pressure in the crankcase that forces out the exhaust while simultaneously drawing in air/fuel mixture for the next cycle. Bottom line: with a 4-cycle you get power with every four strokes of the piston, and with a 2-cycle you get power every two strokes. This efficiency is why a 2-cycle engine produces twice as much power as an equal size 4-cycle engine. You visual learners might find this clip helpful http://youtu.be/bIH4E8waCzo (FYI: the words “cycle” and “stroke” mean the same exact thing.)
How Fast Do You Want to Go? Our 2-cycle TaGs have twice the horsepower of 4-cycle WFs, which have 3-4 more ponies than the Briggs 206. The top speed of WFs falls between TaGs and rental karts. Through corners WFs and TaGs are about the same, but on the straight aways the TaG is an 80mph rocket while the WF sputters on its rev limiter at around 65mph, and the 206 around 50mph.
How Much Time Can You Spend? The mechanical demands of a TaG are significant between events, and throughout the race day. The WF is pretty much squirt some oil on the chain and go. Some people don’t have the time or patience for tinkering, others find hours in the garage to be so therapeutic that it’s the only thing between them and the funny farm. Others pay their kart shop to maintain their equipment and bring it to the track (see the next question.)
How Much Money Can You Spend? Initial purchase and ongoing ownership costs of a TaG are at least twice that of a WF or 206. Let’s break that down…
CHASSIS: While there are specially designed 4-cycle chassis, most WF racers use the same karts as TaG racers. These are about $3,500 up to $6,500 new, or $4,000 down to under $1,000 used.
ENGINE: TaG engines are $3,000 – $4,000 new, $2,000 or less used. Complete WFs engine set ups are $1,200 new, 206s $900. Neither are easy to find used these days.
MAINTENANCE: A Rotax TaG needs the top end rebuilt every 20-25 hours for roughly $500, and a full rebuild every 50 hours for $1,500+. That 50 hours is about a season for an active racer, and there’s nothing but slow laps and a huge repair bill beyond that 50 hours. WFs and 206s are good to go for two seasons if you’re religious about changing the oil every weekend. However, front runners aren’t likely to go longer than a season.
How Competitive Do You Want to Be? Some folks just like to turn laps, others would wreck their grandmother to win, most are somewhere in-between. But really, this is just another way of asking the money question, because money can get you fresher tires, more frequent rebuilds, voodoo curses on your rival (the one to turn him into a goat is not cheap.) Maybe your budget won’t stretch as far as your ambition in TaG, but you’d be plenty flush to race all the best 4-cycle stuff.
How Fit Are You, Really? With speed comes g-forces. With G-forces comes bodily abuse that’s easier to take with reasonable core strength and cardio health. Karting is way more demanding than it looks. Serious health conditions should be taken seriously. Karting is supposed to be fun, not being able to hold your head up for days is definitely not fun.
Great, I Read All That and I’m Still Not Sure. Now What? Easy. Come to a race. Leave your shy self at home and talk to everyone and ask lots of questions. Make a special point to connect with representatives from NHKA Authorized Dealers. Know that everyone in the paddock wants you out on the track racing with us – the more the merrier, as they say. You’ll find everyone eager to help you find your way into the right kart for you.
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