FMX Insider No.6: Two-Strokes VS Four-Strokes

Welcome to our brand new weekly web-exclusive column, Transmoto‘s FMX Insider. Penned each week by South Australian rider, Ben Heidrich, the FMX Insider will present the story-behind-the-stories of the Aussie and international freestyle motocross scenes. 

This is one of the more controversial topics in freestyle motocross and the rest of the dirt bike world… Two-strokes or four-stokes; which do you prefer? In this week’s story, I’ll be talking to a couple of FMX riders who have rode aboard both sorts of bikes during their careers.

I have ridden two-strokes my whole life – from QR50s, RM80s and RM125s to my current YZ250 two-stroke. The only time I have ventured onto a 450cc four-stroke is while doing a little track riding. But for FMX, the infamous ‘two-banger’ will always have my heart!

It is fairly common for an FMX rider to make the transition from a two-stroke to a four-stroke in their career. JC Epidemic rider, Joe Sheppard, has also ridden two-strokes most of his life (mainly Yamahas). He switched to a KX250F in 2008 as he was working in a Kawasaki dealership and the two-strokes weren’t available in the country any more. “The bike lacked the light feel and snappy power of my old YZ, but for some tricks the solid feeling in the air felt like an advantage,” said Sheppard. “The extra engine braking was a little different at first, but it didn’t take long to adjust to it. It was a nice change after riding basically unchanged YZs for so long.”

Sheppard stuck with the 250Fs up until he started riding for the Yamaha-supported JC Action Sports team in 2011. “I had the choice to ride any bike I wanted, and I chose the YZ450F over the two-strokes the other team riders were on,” Sheppard continued. “My main reason behind this was fuel injection (FI). Any FMXers worst fear is the bike bogging on the ramp, and FI helped put that to the back of my mind.”

The extra power of the bike was an advantage for Sheppard, especially on tight competition courses with big jumps or tight ups.

With the new 2014 YZ-Fs having a very FMX unfriendly sub-frame, Sheppard was often questioned about if he would ever make the switch back to the two-stroke. “In my mind, I was never going back,” said Sheppard. “The four-strokes have come so far, and in my opinion their advantages well outweigh the advantages of a two-stroke.” FMX is not very demanding on engines, so maintenance costs on the 450 is very comparable to a two-stroke. “I can’t see myself ever going back to a two-stroke now, especially with the lack of development of the bikes.”

Josh Hannah; FMX rider from NSW, made the transition from a four-stroke to a two-stroke. “So far I personally find the two-stroke better for FMX,” said Hannah. After racing on his YZ250F for years, the Freestyle Kings rider then started his FMX career on this bike (above). He then upgraded to a couple of KX250F bikes. “The four-stroke was good – I find they are a lot smoother and the engine break helps when having to pull up quick if you’re riding a tight venue at a show,” Hannah continued. “The four-stroke being smooth also helped with slippery conditions and run-ups. I found rolling the throttle on with the smooth power of the four-stroke helped with finding traction.”

Hannah upgraded to the YZ250 two-stroke as he was after more power. The 250F struggled making 75ft in second gear and this made it harder for him in competitions having to face double-double sections.

“I find the two-stroke easier to Backflip as they are a lot lighter in the air,” said Hannah. “The back brake slows the bike up if you pull too hard for a flip, and having that extra power to help you spin them around helps too.”

All-in-all it really comes down to the rider’s personal preference. There are definitely pros and cons for both bikes… It really depends on the rider’s style and how he likes the feel of his bike in the air and on the ground.