ACTION POWER SPORTS
Yamaha GPR Race Prep
Home
Polaris Ranger by APS
ATV Performance Parts
Shop Service
Rhino Products
Yamaha GPR Race Prep
Seadoo XP Supestock
Custom SXR 800 By APS
Watercraft 4-SALE
Contact Us
Our Location

APS GPR 1200 Superstock Preps For Racing

APS03Flagship1.jpg

APS Yamaha GPR 1200 Super Stock

To prepare for the 2004 Season I decided to give the GPR a thorough going over. First the motor is removed and a complete tear down and cleaning is done on the Engine. Tapping and Heli-Coil fresh Stainless threads into the case assembly & intake mounting holes

Next the Crankcases are cleaned again and prepped for assembly, New O.E. crank seals are installed with a thin bead of Three-Bond 1211 sealant around the case halves, a small dab of Stud & Bearing Loc is applied to each of the main bearings and PJ1 assembly lube is lightly applied to the Connecting Rod bearings then Crank Cases are torqued to spec.

Torqdcase1.jpg

Prepping the Cylinders was next Using Kawasaki 82.25mm PRO-X Pistons. The cylinders were honed out using a Sunnen precision Hone to achieve exact clearance on each of the cylinders. Then I chamfered the ports and washed them up for assembly.

ProXnCyl1.jpg

CylHone2.jpg

GPRsteve1.jpg

Before final assembly of the front cover I re-checked the pick up trigger clearance using a dab of clay and MSD trigger shims to set the gap between 0.070 & 0.080 clearance. 

Black RTV Silicone and small tie-downs work excellent to insure that the wiring behind the flywheel stays in place during operation. 

After everything is set in place the front cover O-ring is installed and torqued

After Inspection of the Reed Cages I decided to Replace the Pedals using replacement Reeds

The Triple pipes were installed with new O-Rings / Lord Mounts / Clamps & H-D Springs

yamaha-over.gif

Finishedprep1.jpg

Enter content here

Threadchck.jpg

Getting the Crankshaft To Phil @ Crank Works was next where a complete rebuild was done using New Yamaha OE 1200 Rods with SKF Bearings over the O.E. Koyo brand that were on the crankshaft, 

I have seen the MAG side bearing failure on several GPR motors so for additional Lubrication Phil added a second oiling hole that was machined into the SKF front bearing and matched to weep hole in the upper case half. 

Then the crankshaft is trued up & rod pins welded

SKFBearingHD.jpg

Truedup1.jpg

CylHone1.jpg

Then the Cylinders / Power Valve Assemblies & Heads were installed with New O-Rings, Gaskets and a light coat of Assembly Lube and Torque to OE Specs. With the Starter Drive installed the Coupler and Flywheel are also Torqued Down

The NOVI 48MM Carbs were gone over too, complete tear down & cleaning with fresh Diaphragms, 
Needle Valve Assemblies, Needle O-rings & Gaskets. 

Then the Pop-Off Pressure is Matched for each Carburetor.

Fresh Fuel & Water Lines were installed then the Engine is placed into the hull and shimmed for Drive Line Alignment, The Coupler Shaft had recently had new bearings so that step was skipped. The Terminal ends on the battery cables were replaced and New Ground Wires to the MSD Coils were put in.

Setting up the Magnum E+ Setback Pump was next with Fresh OE Bearings and Seals and a Re-Pitched Prop from Dave @ IMPROS the Preparation of the GPR was near

Enter content here

As with All the Work Performed at ACTION POWER SPORTS you will get the best service available with the same type of excelence  I put into my own work. No matter what the level of performance Knowledge you have. I will take the time to explain any of your concerns.
Call me for any questions you may have and I will be happy to assist you.
 
STEVE GOLD
aps@wydebeam.com
 

480-632-5565
Action Power Sports
3235 N Arizona Ave # 12 - Chandler - AZ - 85225