For the Love of Screaming 2-Strokes: Yamaha RD125 Street Tracker

Wilco Lindner’s stunning RD125: Built for the love of screaming two-strokes…

The Yamaha RD125 was an air-cooled, two-stroke twin that boasted 17 horsepower at 9000 rpm and a top speed of 78 mph. It was something of a pint-size screamer, a 125cc lightweight whose power output doubled between 6000-8000 rpm.  Said Motorcycle Mechanics magazine in a 1981 road test:

“This rather lively characteristic is combined with low weight, a short wheelbase and necessarily low gearing. It’s not surprising that you can pull wheelies on the 125 much more easily than you can on the 100 bhp CBX. Whether you intend to or not.”

Enter Wilco Lindner of the Netherlands, who was riding in a mini sidecar before he could even walk and went on to race motocross until he opened a Crossfit gym several years ago. Once that business was up and running, he returned to his two-wheeled passion. First he started on an XR600 project, but what he really wanted to build was a 2-stroke twin:

“Last summer I found one, an RD125. And so began the story. In the process I learned to weld, machine and all things that are needed to complete a build. Not that I couldn’t do anything before, but I learned a ton of stuff.”

Yes, this stunning little smoker is Wilco’s first build, complete with a fully ported and polished engine, one-off exhaust, hand-cut graphics, Derbi-sourced wheels and suspension, and much more. When asked why he built the bike, Wilco’s answer was music to our ears:

“Why, because of the love for screaming 2 strokes.”

Wilco credits Kenny Robert’s TZ750 for stoking his love of flat track — an inspiration you can clearly see in this build. The bike is fully street-legal in terms of lights and indicators, but the decibel level is another matter:

“Over here in the Netherlands there is a noise limit, trust me. This one is not within those limits. It sounds like a real racer, except the speed is a bit lower. But for a 125 it’s insanely fast. Everyone is turning their heads when you pass by on this one.”

Below, we get the full story on this screamer from Wilco himself.

Yamaha RD125 Street Tracker: Builder Interview

• Please tell us a bit abo ut yourself, your history with motorcycles, and your workshop.

My name is Wilco Lindner, 28 years of age and from the Netherlands. I started riding a bike before I could walk — my dad shortened a Vespa (moped) into a mini sidecar, so I could basically ride before I was able to walk. I then did motocross till the age of 24. At that time we started our own business, a crossfit gym and invested all our time into that. When this was up and running I started to get interested in the bike build scene, I then started an XR600 and did this between working out and running our business. This project is still on the table. Because from the start I wanted to do a 2-stroke 2-cylinder, last summer I found one, an RD125. And so began the story. In the process I learned to weld, machine and all things that are needed to complete a build. Not that I couldn’t do anything before, but I learned a ton of stuff.

• What’s the make, model, and year of the bike?

It’s an RD125DX from 1979.

• Why was this bike built?

Why, because of the love for screaming 2 strokes.

• What was the design concept and what influenced the build?

I really like the flat track scene, the TZ750 of Kenny Roberts got me to this point.

• What custom work was done to the bike?

Chassis

Swapped the forks and wheels from a Derbi GPR naked (Dutch moped).

Rebuilt the complete frame to fit the tank. It’s a Yamaha TY50 tank, so range isn’t very far haha.

Custom subframe and a poly rear — what basically started as a sheet metal one.

Protaper bars.

Made all the lights and blinkers work, custom-made it myself so it’s street legal.

Custom shifter and brake pedals.

CNC machined ignition cover by EHR Tuning. He designed it and was kind enough to make me one.

Custom oil tank, what first was a metal one and my good friend Nellissen Technical Support made into an RVS one.

Custom hand-cut graphics, cut them piece by piece, paintwork is done by my dad (CarSpotRepair).

So basically that was the framework. The people who helped saw my project coming together and were stoked to add a little bit of extra by upgrading my initial work.

Engine

Ported cylinders.

Custom manifolds.

21mm carbs.

Tuned cylinder heads.

Hpi ignition.

Calculated exhaust. I had already completely done two exhausts from a scooter that looked cool, but then I started learning new things and decided to calculate and roll them cone for cone into handmade exhausts. Those things took me about a week, but they sound and perform awesome! Tack welded them myself and KiwiParts did the final touches.

• Does the bike have a nickname?

Not Really, believe it or not it’s my first build. All done by myself, except for the upgrades of my own parts and the paint work.
So that is why I call it Build Nr.1 MORE WILL FOLLOW!

• Can you tell us what it’s like to ride this bike?

Haha it’s funny. Over here in the Netherlands there is a noise limit, trust me. This one is not within those limits. It sounds like a real racer, except the speed is a bit lower. But for a 125 it’s insanely fast. Everyone is turning their heads when you pass by on this one.

• Was there anything done during this build that you are particularly proud of?

The fact that I did everything with my own hands, I learned techniques and use of machines during the build. The same as with the covid build, never done aluminium before. But the fact that I completed those exhausts myself while everybody told me that this was such a task if never done before. Just what they told me before I told them all my ideas for this bike haha.

Builder Thanks

Kiwiparts: kiwiparts.nl | @kiwiparts
EHR Tuning: www.ehr-tuning.com | @ehrtuning
NellissenTechnicalSupport
CarSpotRepair

Follow the Builder @builtbywilcolindner