Joel, a race engineer from Bangalore has done a performance build on his Yamaha R15. The modifications are for the street and not a race and thus Joel has modified his bike keeping reliability, economy and rideability in mind. The bike hits a top speed of 140kmph (tested on GPS and Speedgun) with rev-limiter cutting off speeds at 10000rpm). The engine has higher low-end torque than a stock R15 until 5000Rpm and from then on, it gets into the powerband with a stronger pulse. The bike still returns decent fuel efficiency for the power it generates at around 30-35kmpl.

The modifications on Joel’s Yamaha R15 is as follows : –

Engine : –

  • Ported and polished cylinder head with altered port geometry
  • Custom valve springs
  • Stock Valve sizes
  • Reprofiled valve seat area
  • Stage 1 spec camshaft with custom ground profile
  • High compression set-up
  • Modified cylinder and stock piston
  • Fine tuning and set-up corrections
  • Stock airbox and filter
  • Stock throttle body and intake tract

Fuelling : –

  • Stock Injector
  • Stock ECU + coil
  • Altered AFR values for fuelling inputs

Gearing : –

  • Stock sprockets
  • Stock Gearbox
  • Stock Clutch

External : –

  • Stock looks
  • Hand crafted Tuned Free Flow exhaust
  • Full stock weight, no lightening

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