YZ450F Project Bike - Pro Circuit T-4R exhaust system
As a rule of thumb, every fuel-injected bike thrives in aftermarket exhaust systems. Why? Because EFI bikes run flatter on the top than carburetor models and the Yamaha YZ450F is no different.
Whilst the standard exhaust system works well through out the throttle range, it is only so-so in the top end and lacks significant over-rev.
So with the support of Shayne King's Crown Kiwi Enterprises in New Plymouth we bolted on a Pro Circuit T-4R with renaissance chamber race system.
Pro Circuit has joined the renaissance chamber fray in an effort to lower sound in order to meet the AMA/FIM 94dB sound requirements without affecting performance. The T-4R features the same performance benefits as the titanium Ti-4R, the only difference is the T-4R is made from aluminum and stainless steel. Compromising added weight with a reduced price, something we were prepared to do considering I am only just pushing 80kg, weight wasn’t really an issue.
It was instantly
obvious that the T-4R was a well designed piece of equipment and with world
class riders developing it, it shows. The system boosted top-end power without affecting the mid to bottom-end. I instantly noticed an increased over-rev whilst taming the barky throttle response off idle, which is exactly what we were looking for.
Cost: $1,100 Availability: Visit www.crownkiwi.co.nz for their dealer nearest you.  North Harbour Yamaha: www.northharbouryamaha.co.nz/index.php Elf Oils: www.elf.co.nz Crown Kiwi Enterprises: www.crownkiwi.co.nz Graphic Creation: graphiccreation.co.nz GYTR: www.yamaha-motor.co.nz Procut: 0800 4776288 or 021 942039 Renthal: www.northern.co.nz Pirelli, Tsubaki & EBC: www.nwa.co.nz/ Precision Lazer Cutting: www.precisionlasercutting.co.nz Drury Performance Centre: tires.co.nz/accessories.htm Shift, Fox & CV4: www.sportspro.co.nz Lightspeed: www.lightspeedperf.com Dr Trim: http://www.drtrim.co.nz |