Illegal Yamaha 125Z Racing Bike


This article is taken without permission from
Hope they will forgive me!

Please go here for the original content of the page.

What was modded on that bike…?
block and piston
– Original Yamaha 125zR block.
– Bored tu 57mm using DT125(enduro) RK brand piston.
– Ported and polish the block.

Engine head
– OEM header.
– Skimmed the header and polished it.

– Standard Y125z manual clutch system.
– Original Yamaha friction plate.
– GT Racing clutch springs.

Actually that bike got 2 carburetor unit.
– Carb Mikuni for Suzuki Panther 150. [Main jet 300, pilot 28.5]
– Keihin PWK 28mm. Ported to 30mm. [unknown]
– paired with FCCi Racing reed valve.

– Fully Standard. Even the CDi is standard.

– BM Power + YY Pang exhaust manifold + custom made end can silencer.

– Standard OEM front and rear suspension system.

Final drive
– Using 15/34 MCS sprocket setup with TP Racing 415 chain.

– COM* 17×1.4 alloy rims with hi-polish 125z hubs.
– Camel 50/90 tyre. very2 kecik punya tayar.

– Standard front disc brake system.
– Rear disc brake system was removed due to no use of using it.


– None. This bike was staying in the house all the time except when it was needed on the road.

Which shop do all this ?
– my friend’s house. Of coz la this is his bike.

How fast can it go ?

– 180km/h on 4th gear. after that cant calculate due to meter limit is only at 180km/h.
– 16sec for a kilometer.



13 Replies to “Illegal Yamaha 125Z Racing Bike”

  1. In Johor,the new model of 135lc modified and reach up to 267km/h with custom made Thailand parts.You can find in Skudai.Owner is a chinese.The bike was also fully modified with Racing Boy parts.If you have $$$,confirm everything you can reach but also have limit la…

  2. hi chesecake,
    no offend too, but i own a 125z as well, and modification few years back while i was in kolej, used RX-Z carberator, with LC piton, one piston ring, sprocket 14/35, and my 4th gear was hitting the 180km/h already, and can easily exceed 200km/h when using 5th & 6th gear, i tried with RR & RX-Z & is possible, when i ride, i use only upto 5h gear, 6th gear is too fast already bro, so yes, it is posible bro….and the feeling is wow!laju!!!!!!!!!!!!!

  3. No offend bro but 180km/h on 4th gear is impossible based on your mods. Again it is impossible to go 180km/h on 4th gear based on your mods.

    If u said 5th gear at 180km/h then i believe. 5th gear can go even faster than 180km/h.

    But if 4th gear happen to go until 180km/h on your bike, then it must be something with your speedo.


  4. i use y125z..i jus wanna make it a little bit fast..boleh makan rxz sudah la…but without touch block(mengusik block moto,jus kai standart jerk block)..
    apa yg perlu wat ek??
    tolong beri nasihat..

    -fresh border-

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.