Over the years, we’ve been rightly blown away by the first-time custom builders who have knocked it out of the park without any experience at all. But when today’s incredible creation landed in my inbox, I realised there is a group we perhaps don’t praise enough. They are the designers and builders who have literally hundreds of one-off bikes to their name and still manage to find new, cool and creative ways to build a custom. Few loom as large in this space as Tanadit Sarawek, known simply as Eak, the man and the myth behind the global K-Speed brand. And this little beast based on a Yamaha XSR155 is a personal passion project for Eak, who has designed a slick little street scrambler with a go-anywhere army attitude.

To get an idea of just how impressive Eak’s creative imagination is, the K-Speed site currently has eighteen different pre-designed custom motorcycles you can order and have shipped to your door, all based on a variety of motorcycles and in a range of styles. Of course, you can also order a one-off build, and then there is his back catalogue numbering hundreds of builds that includes bikes like big Harleys and Ducati Diavels, right through to his famous Honda Cub creations. Then you have the whole K-Speed parts department, with pieces for bikes from seven manufacturers and thousands of universal components. Yep, he’s never not coming up with something that’s trick and terrific.

But for this build, he wanted to try his hand at working with the Yamaha XSR155 and it’s an interesting little machine. The bike is based on the R15 which has been a super successful mini sportbike for Yamaha for nearly a decade. From that machine, the Iwata factory has then built both the MT-15 and the XSR variant, which are now largely pieced together in factories in Indonesia and Thailand. But being based on the R15 means you get a hell of a lot for your money, a genuine delta box frame, inverted forks and a screaming single which features the company’s variable valve actuation.

Looking at the stock bike, Eak could see there was clear potential to craft a nice little scrambler, but being so busy, there was no time for a concept or design drawings. “To be honest, he produces so many works per year so some of the projects do not have much concept,” one of his employees tells us. So it was simply down to stripping the bike back to its bare bones and seeing what they could create with the Yammie sitting in front of them on the lift. The delta box frame provides great handling, but the factory subframe is a mess. It’s covered in tabs, clips and brackets to hold the factory plastics, seat, lights and store electrical parts.

So, there was just no way it could stay. But having been designed for the sportbike-styled R15 means that seat to tank gap is a real challenge. To solve the problem, all the metal higher than the twin spars was cut off and pieces of tube started to be offered up to come up with a solution. What Eak and his crew decided was to use the subframe to also mount the tank, so as to solve two problems with one stone. Using two different pipe diameters, foot after foot of steel was bent up and welded into place until the finished product was ready for final welding onto the main frame.

Having conquered this, the biggest challenge of the build for the team, they used the new metalwork to remount the factory tank. Now sitting totally level it has drastically improved the look of the stock piece and meant there was no need to fabricate a new unit, with all of the fuel-injection components required to run the bike. Behind this a simple seat base was fabricated and over the top goes one of the company’s signature tuck and roll black leather units, designed to butt up neatly to that factory fuel tank.

Now the whole team could really see the basis for the scrambler transformation come together and to enhance the look, brackets were made to mount an offroad styled fender to the underside of the lower triple clamp. The rear end gets a matching look, with just enough fender pocking out from each side of the up-kicked tail to be a practical mud magnet. Major fab work done and the new frame was all blacked out and that army green with simple K-Speed graphics really sends the signal that this bike is built for a purpose. And as if to ram that point home in an impossible to miss fashion, the tyre selection is the beefy Motoz Tractionator 10/90s.

The 20bhp stock engine with VVA is kept factory fresh, apart from the addition of one of Eak’s signature high-rise exhaust systems which features the company’s own Diabolus muffler. Then the work focussed on really neatening things up, with a large LED headlight mounted hard to the forks and the stock bars fitted with new grips, mini switches, bar end mirrors and a relocated factory dash. To aid in braking, new lines and an improved master cylinder were installed before the rear end was treated to a vintage tail light and tiny indicators.

The end result is a little pocket rocket that you just want to thrash. And if the feedback is strong, expect to see many more XSR155’s from the mind of the K-Speed master.

[ K-Speed ]