A (Barely) Legal Yamaha YZ125

By Rowan Page | Published on 2020-04-21


A (Barely) Legal Yamaha YZ125

I don’t know what possessed me to do it, but a couple of years back I got it into my head that I was going to road legal my Yamaha YZ125. A pure motocross bike with no lights, mirrors or anything remotely road oriented about it. Those bikes don’t even come with a kickstand.

The original 2010 Yamaha YZ125.
The original 2010 Yamaha YZ125.
The first challenge of this project was the biggest; licensing the bike. I had bought the bike 2nd hand with no paperwork whatsoever. I needed a certificate of manufacture and original NATIS document from when the bike was originally brought into the country. Much to my surprise a quick call to the local Yamaha dealer pointed me to the offices of Yamaha South Africa who conveniently were just down the road. A quick chat with them and I had the original NATIS document, as well as a contact from Yamaha Japan to get the certificate of manufacture. Somehow within 24 hours I had heard back from Yamaha Japan with the certificate I needed. It also showed that the bike was a year newer than the previous seller had told me. Another nice surprise.

Now that it would be possible to license the bike the next step was lights. In South Africa you need a headlamp, taillight, front and rear indicators, as well as a number plate light on the rear. The little stator was never going to be up to this, and a bigger coil wasn’t a route I wanted to go. I found a Chinese company online who made a universal LED light kit which included pretty much everything except for the headlight and battery. A quick trip to a local bike shop for a 12v headlamp and the hardware was sorted.

Working on the new wiring harness.
Working on the new wiring harness.

Since I didn’t want to spend a huge amount of money or compromise the bike’s performance, I was going for a barely-legal setup. In the end I jerry-rigged a solution where the light system was powered by 16 AA batteries under the seat. I found series holders for 8 AA batteries from the hobby shop (8 x 1.5v = 12v!) and modified the light kit’s wiring harness so that one set powered the headlight, and the other set for the rest. It wouldn’t work for long, but it would work!

Lights working, but no mirrors.
Lights working, but no mirrors.
The first run at the roadworthy was to test the waters. I cheekily cable tied a blind spot mirror to each side of the handlebars and gave it a crack. The test center dealt mostly with trucks so my dirtbike was certainly much more interesting than anything else going on that day. I am not sure whether this helped or hurt me but, in the end, I was told to come back with some proper mirrors and it should be ok. I returned the next day and just like that, she was roadworthy. Not a care in the world about that there was no spark arrestor in the exhaust or about the full knobby tyres which very clearly said “not for road use” on the side, but I wasn’t complaining! I tried my luck and it worked!

Adding some mirrors.
Adding some mirrors.
A few painful trips to the license department and I finally had my number plate. Of course, I got the small ‘not exactly legal one’, but that didn’t matter. I had done it. I had proven to myself that it was possible. I wish I had more pictures of the build and the bike, but at that stage all I cared about was riding the thing! Riding right through the middle of town and hearing the ring-ting-ting is something I will never forget. You just couldn’t stop anywhere since it still had no key or kickstand!

Road legal but still worked in the bush!
Road legal but still worked in the bush!


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