Refitting the engine on the YZF-R125, now with 180cc big bore kit


not a lot to say here really – engine is rebuilt on the 180cc big bore kit, this is just putting it back in the bike..if it runs then we’re pretty much back in business!

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2 thoughts on “Refitting the engine on the YZF-R125, now with 180cc big bore kit”

  1. …I watched your strip and refit ,

    How did it fair once you started using it regularly ?


    1. That bike is my main means of transport so i use it for pretty much everything, in all weathers and all year round. Since doing the cylinder upgrade I’ve had about 3.5k (in 1.5 years roughly) of more or less trouble-free motoring…in the current loadout with the PCV + autotune she’ll pull 85mph on the flat and top recorded speed so far is 88.

      In the next week or so i’m going to drop the motor out again for a bit of a service/overheaul: do valve clearances, fit new timing gears + timing chain (which should have been done wihen i did the cylinder), and a stage 2 cam..then hopefully we should be good for a while yet and with a bit of luck that ought to take us into the early 90-something mph range 🙂

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