The “Gromaha” – An Awesome Honda Grom/Yamaha YZ250 Mash Up!
This Is The Two-Stroke Yamaha YZ250 Powered Honda Grom: The Gromaha
Ever seen a Honda Grom with a 250cc Yamaha YZ250 two-stroke engine? Didn’t think so! This is the “Gromaha” by Jesse Davis, and it looks like the most fun you can have on two very small wheels. We’re all familiar with the Honda Grom – it’s a small 125cc minibike that has gained a cult following all over the world: it’s a compact motorcycle that’s tough, reliable, minimalist, and a joy to ride, no matter what sized rider is sitting in the saddle. Not only is it fun to ride, it’s fun to customize too, and we’ve seen no shortage of funky little custom numbers and some elaborate engine swaps too. While this may not have the firepower of the Panigale infused Grom we saw a while back, it definitely comes equipped with plenty of bite to match its bark. Some call it the “Gromaha” and it doesn’t take a genius to work out why.
Jesse Davis’s Two-Stroke Gromaha
While the Honda Grom might be worthy of its own sub-culture, there’s no denying that there are two things that potential owners criticize: the size of the engine, and the size of the whole package in general. While nothing can be done about the latter, adding a few extra cc’s into the mix is definitely do-able, and Austin, Texas, resident Jesse Davis shows us exactly how to turn the little Grom into a fierce two-stroke beast.
After ditching the original MSX125 single cylinder engine, Jesse sourced a two-stroke Yamaha YZ250 engine and transplanted it into the chassis. The power increase was astounding. The Grom’s stock engine produces a rather paltry 9 hp…but now with the Yamaha unit in place, the Gromaha now produces a rather impressive 49 horses. But that wasn’t enough. To make sure the most of the new engine, Jesse added a TYGA-Performance exhaust kit for extra madness. Thanks to the new expansion chamber, an upgraded radiator, the Gromaha reached a new level of craziness. But wait, there’s more. As a final touch, Jesse upgraded the suspension to include the front forks from an Aprilia RS125 GP racer coupled with a JRi rear shock for the ultimate ride experience.
This is arguably one of the most potent Honda Grom customs that we’ve ever seen: it’s had a phenomenal power boost that came without compromising the small and compact appeal of the legendary Grom. Who’d ride it? We definitely would.