2002 Yamaha GP1200R
2004 Mods and Madness
There just aren't any "kits" made to get the GPR to handle the real world. Some offer blazing top speed. Others offer handling like a slot car. Others are ticking time bombs waiting to either "high side" you, or blow up. I'm looking for a boat that goes like stink, tracks like a champ, and cuts through waves like a knife through butter. I feel like I've sacrificed engine longevity with triple pipes... but the rush is out of this world! I must keep them now.

Goal:
Glass water speed of 85.
Race condition speed of 70.

Currently:
70 mph/ 8200 rpms in race trim.
81mph/8200rpms in smooth water trim

TBD:
Rad Gauge to equalize testing conditions.

Intake...


FOR REFERENCE: Stock jetting, and piston wash.
MAG CENT PTO
MAIN JET 117.5 117.5 117.5
PILOT JET 95 95 95
HIGH TURNS 1 1 1.25
LOW TURNS 1.25 1.25 1.25
NEEDLE SEAT 1.2 1.2 1.2
SPRING GOLD GOLD GOLD 
  LINK
LINK
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 MAG   CENT   PTO 
Main Jet 150 150 150
Pilot Jet 110 110 110
High Turns 3 2.5 2.5
Low Turns .75 .75 1
Needle/Seat 1.5 1.5 1.5
Spring 95  95 95 
Return Jet 60
2.75psi @ dle 6psi @ 8000
 same same
Return Jet 70 same same
Piston 
Plugs
Cranking Compression

Flywheel/Snout Lapping and Radius...
Took the crankshaft and flywheel down to Crank Works and showed Phil what I read should be done to prevent flywheel chatter and breaking of the snout. After much discussion, he radiused the from of the flywheel to the snout area, and I used his porting bench and some grinding compound to lap the flywheel per instructions found on the Riva board. I also used RED locktite between the two items and torqued it down to 100ft/lbs. Your mileage may vary. There is hope... a new crankshaft design is on the way...

Crankshaft Support...

After talking to Larry and Mark down at RPM, I decided to spend the cash and put on the crankshaft support. In the middle picture, you can see the bearing support that takes the majority of the abuse. It will need to be changed out every 30 hours or so. I'm at 32 with no deflection. I'll change it at 40 regardless.

"Mc" Cooling...


RPM Case cooling. Nozzle was drilled/tapped with a 1/8"npt 3/8 elbow barb, and using the old siphon hole in the transom, routed to the RPM  radiator, then out the front right hole. I'm using a 14 vein pump with R/D Triple 1/2" cooling lines, plumbed to the Factory Pipe triple pipe flanges with 1/4"npt 1/2"elbow barbs. Also the flange gaskets have been opened up to cool the cylinders better. The 1/8"npt 3/8" elbow barbs are used for the pipe chambers, using about 2 foot of hose per pipe. , 10 total pissers. This is my 4th attempt to cool this beasty.


"Mc" Engine...
The stock ART pistons that were removed during the 30 hour tear down, showed cracks at the pin bosses, per RPM. I'm done fighting that battle. Crank Works true/welded crank spins stock rods and ProX pistons (D) ceramic coated from HPC to duplicate the coating on the stock Yamaha ART pistons. Also added the HPC anti friction coating to the side walls. The stock flywheel has been radius cut and lapped to the crank. The cylinders are 66E (800 cc) stock cylinders with no polish or port work. The heads are "Rius-Miller heads with 38 cc domes, drilled/tapped for extra water flow, using Jet Works flow valves to equalize water flow due to the Skat Trak setback 14 vein pump having low pressure at idle speeds. Stock reeds were utilized due to failures. RPM reed stuffers were used to help with reed longevity. Riva/Boyeson reed stuffers were used. RPM modded carbs topped it off. Fercho supplied flame arrestors will soon be installed with water socks. Home Depot supplied the gay yellow hose. I wanted blue!!! The Riva gas power valves are using Sea Doo green bellows, Dan Lamey SUPERDUPER light rusty springs supplied by Fercho. The Sea Doo caps are grooved and zip tied to prevent popping off, also by Fercho. The Factory Pipe triple pipes are of stock configuration, but the pipe cooling is WAAAAY different, using a deviation from the theme from Rius. The stock pipe jetting is in place, but will be looked at in the future. The premix fuel is supplied from 2 fuel lines from the Fercho designed pickup/filter and dumped through the RPM I-bodied modified stockers. The return jet is a 60, but I will experiment with a 70 over winter. Pressure is monitored by a Fercho designed gas pressure gauge.  I used hydroturf, glued to the waterbox support, and removed the rubber pad on the box. 

Electrical...
Parts: Garmin GPS 3 with remote 12v, no battery. Advent ignition, Triple Pump gas curve, Rev Limit 7500, dash mounted electrical switch controlling bilge, egt, and gps. Riva Battery Relocated to rear of hull. Using the old battery compartment for storage. Fuel pressure gauge is mounted where the old bypass switch was, and is installed in the gas return line before the restrictor jet, using a 5/16" tee, a barbed fitting, and a rubber gasket for backing material.
 

"Mc" Handling for the REAL world...
Goal: Tame the porpoise, without losing top speed.
Are you looking to go fast in smooth water by yourself, with a gps, or are you looking to win races both on and off the track? There is NO GLASS WATER where I race, but maybe some smooth water grudge racing in the dead of winter!!!
Parts: ProTec Sponsons, and stock ride plate cut to fit the Riva Mechanical Trim Tabs. R&D Aquavien Pro 2 shoe and grate. Yamaha 3 degree XLT pump wedge, and R&D auto-drop rec. nozzle with Riva mechanical trim tabs. Currently running a 14 vein Skat pump, with Skat prop. No test data at this time. 



 
 

 
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