Yamaha Blaster Porting Type Options

NATIONAL Midrange (midrange)

HIGH REV (top end)

All PTR porting types same price.
PTR Porting and Stock Head Rechambering $595.00

*Cylinder Boring and Piston are not included in price. DRI can bore cylinders and supply new piston at addditional cost

Models
Fits:
Yamaha Blaster all years

Cores Required
Cylinders and Head
*Customer must send in their cylinder and head from PTR Port modification or purchase new cylinders direct from DRI

Power Emphasis

NATIONAL Midrange: Good low end throttle response, excellent midrange, good top end,
likes to pull a taller gear
Best Carburetor: 34mm PJ Keihin
Best PTR Pipe: Midrange

HIGH REV: Fair low end throttle response, Good midrange, excellent top end,
Revs out Very Well
Best Carburetor: 35mm PWK Keihin
Best PTR Pipe: High Rev

Power Gain
20% over stock, peak

Reliability Rating
With proper maintenance, PTR Porting is 85% reliable as stock

Application Recommendation

NATIONAL: Motocross, Sand Dune Riding, Trail Riding, Gran Prix Races, Woods Riding
*Best Overall PowerBand

HIGH REV: Drag Racing, Hill Racing, large TT's and Flat Tracks

Special Notes
DRI has spent 1000's of hours testing, doing R&D on 2-stroke port types and designs. There are no quick read manuals to explain the complexity of 2-Stroke porting.
Data must be gathered and recorded and analyzed, to help properly design cylinders that not only perform properly but give the reliability and consistency expected from DRI

DRI PTR ported cylinders have won more Pro ATV Races and Pro ATV Championships than any other company in the world over the last 2 decades

All port work is 100% guaranteed

All PTR cylinders have port timing degreed in and all port dimensions are blued and scribed for MAXIMUM consistency

PTR Porting is a labor service modification

All PTR porting is performed in house

All PTR ported cylinders and individually serial numbered. With data recorded in a DRI data file, for future reference

For Maximum performance and reliability with a PTR ported cylinder it is imperative the piston, rings and cylinder bore are kept good conditions.
Piston clearance should ALWAYS be kept under .005 of an inch

Quality Cylinder Boring and Proper Port Chamfering is critical to the performance and reliability of your cylinder.
When these services are required for your engine, be sure that they are performed by DRI or a highly trained technician

DRI does not offer a big bore kit for Yamaha Blaster due to reliability concerns

Paul Turner Racing Products are a proprietary brand of Duncan Racing International, Inc.