111cc SUPER PRO KIT

50mm BORE, 56.5mm STROKE, 11:1 COMPRESSION

#SP105  $1,822.00

Go big with your 50! Developed, designed and manufactured in the USA. This kit has it all, just send your crank to Powroll and 3 weeks later, you'll receive everything you'll need. No additional machining required, just install the Powroll components in your engine like stock parts.

INCLUDES:
Powroll Super Pro Head: Big valve head, ported and blueprinted by Powroll Technicians.
Hardweld Camshaft: Profile designed specifically for the 111cc kit.
Keihin Carb Kit: Featuring Powroll's hand-built high velocity manifold. Perfectly matched to the Super Pro Head. Comes with extra jets, manifold, gasket, throttle & cable.
50mm Hi-Compression Bore Kit: Forged Piston, pin, rings, clips, headgasket, basegasket.
Cylinder: Bored and honed in-house to Powroll’s exacting specifications.
56.5mm Stroke with Tough Rod: Includes Powroll Tough Rod, crank pin and needle assembly. Work done on your stock crank assembly.

REQUIRES:
Send in your crank for modification. Download our Stroker Booklet for details. You will need lower end gasket kit from Yamaha for re-assembly. We also recommend purchasing a shop manual for general installation instructions and torque specifications.

EXHAUST - THRUST CHAMBER - SPARK ARRESTED

#17103 $45.00 Sale Price $24.95

This CNC machined billet piece works in tandem with your excellent stock exhaust system for better power without increased sound levels. Performance similar to many complete aftermarket exhaust systems! Better throttle response and increased top end. Works with stock spark arrestor.

PISTON KIT - HIGH COMPRESSION

#00357 $250.00

47mm (standard size, 85cc) forged piston, 11.5:1 compression

Great add-on to your GYTR kit - Designed as a replacement for the low-comp GYTR piston.  Higher compression adds better throttle response, increased torque and faster holeshots.  Billet CNC machined piston for bullet-proof performance, even in the toughest conditions.

INCLUDES: Piston, pin, rings, circlips, headgasket, basegasket

REQUIRES: TTR90 or GYTR Cylinder and head.  Check cylinder clearance, Powroll recommends no more than .002".  May require rejetting.  Premium pump fuel ok.

STROKER +4.9mm

#16030  $260.00

93cc’s with the GYT-R 47mm Piston
Effortless wheelies and big torque for your little TTR.
INCLUDES: Work done on your stock crank. If parts are needed, they will cost extra.
REQUIRES: GYTR piston & cylinder (Yamaha part # GYT-1P605-50-00) or equivalent (GYTR piston works with no modification, other pistons may require modification to fit).
Send you crank for modification.

ON YOUR CORE #12753 $195.00 (GYTR CAM ONLY, NOT STOCK TT-R50)