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Discussion Starter #1 (Edited)
It's 3am and I finally finished fitting a set of gen 1 Busa forks on a 1977 Yamaha triple.

It took pressing out the busa stem, swapping different steering stem bearings (the upper one was tricky finding the "right" one), some creative spacer placement for the space between the upper bearing and the upper triple, swapping out different wheels bearings to use the 19" stock wheel, and machining up some axle spacers.

Woot!

<a href="http://s220.photobucket.com/user/jcwk12r/media/busaforks-1.jpg.html" target="_blank"><img src="http://i220.photobucket.com/albums/dd94/jcwk12r/busaforks-1.jpg" border="0" alt=" photo busaforks-1.jpg"/></a>


I know it looks like shit right now... just wait, it's coming together quickly.
 

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Discussion Starter #3
dohalloran said:
Good luck with that.

Hopefully no speed wobbles.
Yeah, I don't pretend I'm going to go fast on the thing. It'll be mostly a poser bike.

I bought the forks on ebay for $270. To get the old forks up to par with new seals, upgrades springs and a general reconditioning would have cost that much. It's amazing how many "spare" parts for the busa there are.

Old steel frame, triple engine, cafe seat, 19 inch wheels.

I almost feel like a harley guy! :teeth
 

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Discussion Starter #4 (Edited)
latest pics...


I want to make the rear out of aluminum, but that would require some welding skills and equipment that i don't currently have. So it might have to be fiberglass.



headlight off a vrod, forks and triples off a busa. keeping the 19" front wheel which means I'm stuck machining rotor spacers.

But I hope when I'm finished it'll look like a lean mean not so clean triple machine.

Anyone use oxalic acid as a rust remover? I mixed a little wood bleach (oxalic acid) with a gallon of water and sprayed and soaked rusty spots on the frame and it bound the rust and scrubbed off. Even left the paint intact.
 

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Discussion Starter #5 (Edited)
Trying to keep costs down, I used bits and pieces from other bikes rather than doing a lot of custom work.

Kawaski Zephyr piggyback rear shocks, EBC front and rear rotors for a ducati (with 5mm rotor spacers), calipers from a TL1000S, brembo RCS brake MC, clip ons and clutch perch from zx-10r. Stock yamaha headlight mocked up, not yet mounted. Of course the busa forks and triples with the stock wheels and custom axle spacers.



Next up is finishing the caliper spacers and freshening up the engine.
Can't wait to ride it.
 

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Discussion Starter #7
no love for the old triple

Engine is apart and I'm contemplating mods for the bike.

I think since it's already a POS, it'll be a good opportunity for me to port my first head.

After a week or two of reading idiotic forum posts about how to port heads and sifting through endless useless websites, I think I've got a plan.

the two parts I'll concentrate on are the valve throat- the narrowest part of the head just above the valve seat. And the short side radius port shape. My goal is 90% valve size at the throat and a slight bit flatter (less rounded) floor at the short side radius. Other than that, the chances of ruining flow is too great. Oh yeah, and cleaning up some of the casting imperfections.

Then I'll have it slightly overbored/honed +0.25mm with new pistons and rings. Have a good 3 angle valve job done. And put in a megacycle hot street intake cam and switch the exhaust cam for a higher lift intake.

Oh yeah, forgot about the Mikuni flat side carbs.
Ouch this is gonna hurt the pocketbook.

Then, I might have a whole 65hp to the rear wheel!!! LOL.
 

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Discussion Starter #8 (Edited)
Here's my attempt at fabricating a metal seat. About 1/2 done.
Tank is stripped.

Engine is in various parts of the country getting modified.

 

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Discussion Starter #9 (Edited)
small update. seat's been ghetto welded. :teeth




As for the engine, the trans is in FL, the crank should be there soon, the cams in CA, the cylinders and pistons in WI, the head and cases will go out to AZ sometime.

Race to spring is ON.
 

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Discussion Starter #10
I was really unhappy with the rear. Something warped while welding or I bent the metal sheet slightly wrong but the right side back was higher than the left side. Noticeably so.

After banging, bending, pulling I still couldn't get it right. The form was pretty locked in with the seat pan welded. So, I ended up heat shrinking the metal and finally got it close enough to set up the rear panel. Whew. I'm anal enough that I would have tossed the whole seat.

My wife came out to the garage and said I'd better stop or else I might wake up the neighbors.



 

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Discussion Starter #11
almost done mocking it up



the exhaust tip needs to be fixed up and the back of the fender cut, but it's coming slowly...

Here's a blurry pic of the cool stock exhausts I'm using from a '76

 
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