So the story about this little project. I actually picked this bike up as a little side project for myself and to share on Patreon.
The bike is a Yamaha TZR 125R from 1994. It’s a pretty rare bike that wasn’t actually made by Yamaha but by Belgarda, which was Yamaha’s distributor in Italy back in the 90s. The VIN of the bike doesn’t actually say Yamaha, it says Belgarda. As far as I know these were never officially exported outside Europe. The 125cc market was a big deal back in the 90s and there’s a whole history chapter there. These bikes together with the Honda NSRs, Suzuki RG125, Aprilia RS125 and a few other bikes were the most desirable thing a learner could want. They were the stuff of teenage dreams. Pretty expensive though so all the kids wanted them but only the rich kids actually had them. Despite the minuscule displacement this bike allegedly churns out 32 horsepower, probably at like 200 rpm before it’s 11.000 rpm redline. The bike code is 4DL and the 4DL engines are very sought after because they were manually modified by Belgarda before install. The engine is actually a Minarelli unit with very obvious signs of hand porting on parts of the cylinder.
This video is made of up of bits and pieces of 4 separate videos I made on Patreon over the past months. I actually bought the bike without properly testing it or anything. Rented a car with a tow hook and a trailer and drove around 300 km to pick it up. I got to the location in the middle of the night in the pouring rain so I really couldn’t properly inspect anything. So I just bought it. I expected a runner but it wasn’t.
After a lot of troubleshooting trying to start the bike I realized that it actually had very low compression and that likely something was wrong with the engine so I decided to get the engine out which is an absolute joy to do. Takes about 30 minutes. Once it was opened up we found that inside it was an absolute horror job. Someone attempted to rebuild the engine but had no idea what they were doing. The piston was installed in the wrong direction (even though there’s very obvious notches to show you where it’s supposed to go) and because of this the little pins that hold the rings in place where in the wrong place so they eventually got knocked off and made a massive gouge line in the cylinder which ruined the compression and the engine. The crankshaft width was also set incorrectly and the crankshaft nose was bent by someone who didn’t know how to remove the magneto from it properly. So we fixed all of that. The cylinder couldn’t be saved but fortunately I managed to get a new one, got a brand new over-sized piston, had the new cylinder re-bored (fortunately the 4DL engines aren’t Nikasil), got all new gaskets, a new starter and put it all back together.
Some of you might be wondering what happened with my Kawasaki GPZ 900R project. Sadly I had to sold that bike. Reason number one is that it was far too much bike for someone with next to zero riding experience. Reason number two is that I discovered that the frame was bent so I sold it for parts.
I think this bike will be less dangerous and should allow me to experience the joys of motorcycling in a manner more suitable to my skill. I think the bike is pretty cool as it echoes a really cool era and I kinda always wanted a two stroke.
A special thank you to my patrons:
Peter Della Flora
#d4a #2stroke #twostroke