YZ125 Build
We set out to learn more about the new generation YZ125 and build a trick bike ready to hit the tracks.
First step was taking a brand new YZ125 pre delivering it and taking it out for a shake down as it was broken in. First things noticed was poor jetting and not very smooth acceleration. We loved the new ergo’s of the new generation bike and was a great advance to the previous model of this bike.
Jetting – We started playing around with jetting at the track and went from a 62 pilot to a 58 pilot and re adjusted the mixture screw, we then went to a half clip leaner needle on the third clip NYCG. This made the bike much better, we noticed the main jet slightly lean on heavy loads so also went to a 165.
Then after pondering what was next we decided to go all out and fit a GYTR performance kit
The kit retails for $4625 but has everything you need to make the bike a little screamer.
GYTR exhaust and muffler, GET CDI unit, ported cylinder and GYTR cylinder head, carb settings, V force reeds (the bike come standard with V force reeds however)
The kit is safe to run on pump gas and gave the bike a great performance upgrade from 35hp peak to 38hp. (dyno chart in images)
We then played with the carb more and had some luck changing out the leak jet and going richer again on the main jet along with running the Y3 needle that come in the kit.
We now have a little screamer that is still reliable and runs much smoother and cleaner than the standard bike.
Next was the handling, we decided to go from the standard Bridgestone tyres to Dunlop MX33 a tyre we love and trust.
Next was suspension, Ohlins offer a cartridge kit for the fork for this model but we got excited and wanted to do a complete fork the RX48. This is the fork for the YZ250f and YZ450f but we fitted to the bike, the biggest thing was we had to go to the 4 stroke YZf clamps, we used and EZE top clamp and OEM bottom clamp. The EZE top clamp give a heap more adjustment for bar positions than the stock YZ125 clamp. The YZf clamps reduces the triple clamp offset which also seemed to be a positive on track.
No bike is complete without 74 works coatings doing the brakes, engine cover and water pump cover. MX Ink graphics going for the race team look, strike seat cover and some Zeta bling.
We can’t wait to get some more ride time on this bike and continue to refine it as we go. All parts fitted can be purchased through the store, these parts and more can be viewed also on WBR Online https://wbrmotorcycles.com.au/shop/
