QUOTE=Whale;559861]Well im wanting to Go Bigger:Banane09: in the engine department.
Where do I get a Yamaha GP 800 66E engine and electrics?
Do I have to run a bigger pump and will I have to mod to fit the pump Shoe?
Do I have to Mod 155 Drive Shaft?
Let me answer these questions:
I have bought parts for 3 GP800 motor off of eBay. It takes time to do, but it can be done. You never know when parts come up on eBay, so you have to be looking for them all the time. All the parts you need come up for sale at different times. You can of course just buy a complete motor. Some of it you won't need. Here is what you need to be looking for: engine cases with the rear feet attached and all the bolts to bolt it together. You have to ask if the feet come with it and if you can have all the bolts. You need a good used crank. You need a front cover with stator. You need the electrical box and the goodies. If you go with MSD, all you need is the front cover. You need a starter bendix, and starter. You need to determine what cylinder you want to use. GP800 or GP1200, GP1300. Buy two bad ones that need to be re-bored. Once you have your cylinders you will need a set of pistons (rings, bearing, pin). You can choose about any size piston out there. Allot of people have chosen to go with
87mm. This will give you a 927 cc motor. Once you have your cylinders and pistons, you need to send them off to get bored and replated. Cost about $460.00. I know I just did it. Then you need a head. You can find used Riva head from time to time on eBay. WDK sells a head for $300 non girdled. I recommend this option. You need a set of gas power vales - $320. You will need to buy seals and gaskets for lower end. You can pick up a set of reeds cages off eBay. I recommend buying new reeds. You never know how used they really are. You need a flywheel. Now you have the parts to build a motor. Now you will need carbs, intake manifold, exhaust system and the WDK mounting bracket. Go to Jeff's web site and price the intake, exhaust manifold with pipe = 1500.00 (new dry pipe), and your mounting hard ware. Buy a set of big carbs 46 or 48 or 49 mm.
Some of us are using 144 or 148 mag pumps. I recommend using the OEM 144 size pump to save money. You just have to use a taller prop if you go with a 927 built motor. This way no new pump shoe is involved.
If you buy a used complete motor, you would probably want to buy a new head to bump the compression. You can't use the power valves very easily. Stock bore is OK, but the motor really wakes up with 84 - 87mm pistons.
No you will not have to mod a 155 drive shaft. All you need is RN drive shaft to use in a 155 pump. The shaft is the same, but the lengths are different. So for any Yam pump, all you need is a SJ drive shaft.
I built two motor this way so if you need more info just PM me and I will be glad to help.
They are really fun to ride and very reliable once you get it dialed in. They can be expensive to build if you rush into it. I built my 927 with MSD for around 6K. That includes all the stuff from Jeff with out the mounting bracket since I put it in his REV hull. I did it over time and paid for parts and it didn't seem that bad. Only once I put a pin to it did I say holly crap.
Dale
