[BusaTransplant]

Build Start Sunday December 6th 2021

Stem Bearings ordered from All Balls for about $55, great for peace of mind on a seamless swa

Cut my old “drag bars” in half and shortened them, then drilled a notch in both sides for the outer bolts to break the bars from turning or slipping.

Well, here is the start of my first build. Bike I started with is a 1980 GS850G. Engine, front forks, front brakes, and front axle are all from a first gen Busa (most busa parts from a 2001).

(this is pre-disassembly pic not starting point for build off 😅)

 

[BusaTransplant]

Need to shave down this castle nut for clearance to put a cotter key.

This is swing arm fitted up with new bolt, still needs spacers.

If you look close, I had the original GS swingarm bolts machined to fit a 14” long 5/8” plated through bolt for the GS1000 chain driven swingarm

 

[BusaTransplant]

Also minor post but making a to-do list (sorta)

-make spacers to keep swing arm centered
-spacers for front wheel to center GS wheel on Busa axle
-make steering stops
-makes spacers for front rotors so Tokico 6 pots clear spokes
- test fit engine and fab mounts (yep a big one )
-mount make bracket to mount motoscope pro
-figure out air box situation
-make battery/electrical box
-sort out wiring harness/routing etc.

-paint/powder coat
-assembly

 

[BusaTransplant]

Also items purchased so far:
2001 hayabusa engine, ecm, tb’s, (FB Market Place $2600)
1st Gen Hayabusa forks, bars, clutch/brake and throttle (eBay $700)
GS1000 swingarm (eBay $70)
GS1000 chain driven rear wheel (eBay)
GS850 front fender to resize (eBay)
Hayabusa velocity stacks for air box (eBay)
Hayabusa intake boots Incase mine tear when pulled off to paint engine (eBay)

new stuff
Radiator (eBay)
Oil cooler
Water pump
Oil pump
Fuel pump
Fuel Pressure regulator
Starter
Stator
Rectifier
Clutch
Front 17t sprocket
Chain
Clutch & stator covers
Rizoma grips/throttle
MotoGadget mUnit Blue, MotoScope Pro, and wiring kit
Bearings from All Balls for front wheel to hayabusa front axle, rear wheel, and Hayabusa fork/triple to GS
(I’m sure there’s more just drawing a blank at the moment)

and rear sprocket machine locally by Novelty Machinery for 40t hayabusa sprocket on GS1000 rear wheel.

 

[BusaTransplant]

started fitting up a bit more seriously. Now I need a bit of advice on how close to the swingarm pivot point my tail end of my engine and sprocket should be, also what kind of lean angle can I put this engine at doing that and keep it from starving for oil. And lastly I need to find some boots to go from the throttle bodies to the engine at a 45° (yes I’m aware it’s probably not as ideal for the atomization of the AFR but I‘VW got a slight space crunch) any help is appreciated! Thanks

 

[BusaTransplant]

lower rear engine mount made. Weld is ugly as sin but will be fixed and cleaned up after the motor is dropped back out. Headlight bucket is mounted. Need to verify chain clearance then front engine mounts will be imagined. All in all some good progress today.

 

[BusaTransplant]

Well, after more test fitting and fab work I got the battery and ECM box made and fitted, got the fuel pump mount set(made sure the rear master and reservoir clear it). Got the rear motor mounts set so the engine can stay in place without a jig or ratchet straps, and have a good fuel tank with similar mounts on the way to use the mounts from it to fab a fuel tank to accommodate the carbs and an airbox. Also ordered new coil packs because after a mishap with fitting I mashed the top of one, also ordered 1/8” NPT 90° x 5/16” barbed fittings to go to and from fuel pump. Will be working out a Motoscope Pro mount coming up, front engine mounts, FPR mount, and plenty more! Found out the MIG was out of argon (serious rookie moment facepalm) after I get more argon I’ll be making these fit up welds much better. Also got the wheels in to get powder coated(color is “goldtastic”) hope you all enjoy the update

 

[BusaTransplant]

I got my used tank in, took the top off, and started trimming to get a fit for an intake. Got my water pump replaced, low pro crankcase Breather, thermostat, and got some more cleaning done on the engine and TB’s. Plenty more work to go.

 

[BusaTransplant]

having to re-seal that long a seam on a steel tank gives me the fear , i'd get pin holes

It’s definitely a concern, I’m gonna try to get some good practice with some silver solder for the final over any welds.

 

[BusaTransplant]

So I went with my original tank(I decided I didn’t want to form a whole tank) so I just took the sides off and modified the bottom of the tank. Also added tubing channels to let the fuel move back to the back when it gets lower. It’s not pretty yet, but I have plans and I’m pretty optimistic. Besides, once the sides are on and these are covered it will look like a normal tank. Also going to have to get creative with the fuel level sender. With the addition of the humps to accommodate the Airbox I made an obstacle for the natural orientation of the fuel sender.

on another note, finally got my moUnit Blue today. Just waiting on the crimp tool and the Mizu connectors. Then it’ll be game on to start the wiring(Motoscope Pro, mo.Unit Blue, wiring kit for mo.Unit, breakout box B for some of the gauge stuff, and the busa ECM.

Also got my wheels back from powder coat, only to send them back. The hub had powder coat on the outside, inside, and brake rotor seating surface. But that is the color.

 

[BusaTransplant]

so it’s been a bit since I’ve added an update. Had Covid and couldn’t go to the shop for a week. Since then I’ve shaped the tank, still needs a little filler to smooth out the finish though. I’ve made some progress wiring but still have more to go! Also have the Motoscope mounted and mUnit mounted.

 

[BusaTransplant]

looking great would love to know how you sort out the sender couldn't get my fuel gauge to work with moto gadget pro

got the fuel portion to work today. After setting up with the breakout box B there is a config option to set empty and full reading then it references between them to give a mid range value.

 

[BusaTransplant]

got all the wiring for the headlight and front/bar end signals done, painted the top clamp and the bars and played with the Motoscope wiring and settings a bit. Gonna rebuild my clutch master tomorrow, get plugs for my tank and start doing a final strip to prep to seal it, then start on the rough external finish of the tank, and more wiring tomorrow!

 

[BusaTransplant]

well unfortunately I won’t be meeting the build off deadline, but I’m still shooting for Friday optimistically. Guess I overshot a bit on my first build. But It’ll provide some better perspective for my next build when I get there

 

[BusaTransplant]

well it made it to work I’m gonna try getting it in to the local dealer to hook the scan tool up to it. Currently having an issue where while idling after it gets warmer/closer to operating temp that the fuel pressure starts to drop and kills it. But it runs great while warming up!

 

[BusaTransplant]

Chad Hamilton

Well, the bike finally runs! Burned out the crap and baked the heat wrap on the exhaust.

www.facebook.com

here’s the bike running

 

[BusaTransplant]

Great build. Totally mad sticking that engine into that frame, but very nicely put together

Thank you!

 

[BusaTransplant]

Super sleeper, Dope build. Think one of the most creative swaps on here

Thank you 🙏