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[Millietant]

It looks really really good and I'm loving the mods, can't wait to see it with the seat and screen on 

But........looking at the way you're doing the mods, you're not going for a "touring" bike, so I wondered why you fitted the much longer FZ1 swinging arm, rather than the shorter YZF 1000R (Thuderace) swinging arm ?  Or are you going for the drag-bike approach ?

[Modo]

No, not touring, but would do fine I think. Def not drag either.
I actually shortened the swing arm. It's off of the back end; the tire almost rubs the cross rib. Ended up only 3/4 or 1" longer. Sadly I wasn't documenting much at the time. And I never even thought of the YZF. The riding style when this thing is finished will be a lot more relaxed anyway! And it has longer bars for more leverage. 🙂

[fj1289]

Not sure I understand the reasoning to fit a shorter swing arm.  I know it is supposed to make the bike turn quicker and with less lean angle the shorter the wheelbase - but it also means less weight on the front. Would that potentially lead to the front end washing out easier?

I'm definitely not at the skill level to make use of handling mods of that level - especially not on public roads.   I'm sure I'd be hard pressed to feel the difference between an inch either way     Mostly a theoretical discussion for my type of riding!

[Modo]

The dynamics of motorcycle handling is extremely complex and I understand only a tiny bit of it. Basically you are correct though, the longer wb will make for slower steering but add to straight line stability. Then the ride height, steering angle, rake, trail, and the list goes on, all contribute. Now that I've changed so much on it, it would probably take back to back rides on it vs a stocker to really know. 

[giantkiller]

After changing my 86 to the gixxer 1000 front end and switching to the Honda rear shock with the highest rate spring the stock valves could handle. Slightly raising the rear. I knew it was better. But I didn't even ride it in stock form. So had no reference.
So I asked my next door neighbor. Raced gsxr1000 locally. Third in points Elkhart lake and the Illinois track can't remember the name.
He really didn't want to take it for a ride. But he reluctantly did... He was gone so long I was really getting worried. When he finally pulled back in the driveway I could see his huge smile through his face shield. He jumped off the bike. And as he was staring at my bike he said I don't know what you did to it. But the geometry is just right. He said it turns in better than his race bike. He said he took it through the corners he takes the race bike through. When he's setting up the suspension. And he couldn't get it unsettled. He had some factory sponsorship from suzuki at the time. He later had full sponsorship from skidoo/Bombardier for snocross. Awesome rider.

[giantkiller]

Would really like specifics of what you have done to your bike and how it feels when you get it done. Looks like it's going to be awesome!!!

[Modo]

I like what you did with your '86! Makes me wanna get mine back on the road! Mine will be a bit higher in the rear as well and I'm sure I measured how much at one time. The shock is a Penske w/remote res and I've tried to mimic the FZ1 geometry with the top mount. It's pretty much vertical and I know I'll need a stiffer spring than it has. Do you know what spring rate you ended up with? The front of course is just FZ1 that's plug and play in the FJ with FZ bars and all that.
I lot of what I've done is for aesthetics (to my eye anyway). Ton of work on the R6 tail conversion. The top cover for the tail I made from some kind of lightweight composite. Paint is by yours truly as well; I put FJ1200 on the fairing with a ghosted in pearl under the clear as well as some striping on the rear top cover. Pops in the sunlight. I machined the footpegs, and mounting plates from billet. Planning on 3d printing a mount for the remote reservoir to hang on the left side. Modified a chainguard to a minimal look and added some lightness to the front sprocket cover. Need to take a few more pics I guess.

[giantkiller]

It's been a while. If I remember right It's an eibach 900lb spring the Honda guys said that was as heavy as you can go with stock valving for the Honda shock.

[Modo]

I think my Penske has an 800 lb on it(??). Seems like I came up with 1000 needed. We'll see.
What Honda shock did you use, 900rr? Curious I am.

[giantkiller]

I believe it was a cbr600 f4i shock. Several had used them on the fjs at the time to raise the rear height. It's been a long time. I had visited the Honda forums and talked with them. They said the heaviest spring you could put on it with out revalving it was 900lb. So that's what I put on it. It's still a little soft. But I weighed 280 at the time. All muscle no fat. Now I only weigh 240lbs all skin bones and flab.
It handles great I can walk the back tire spinning as it wheelies out of roundy rounds. Very predictable. When there's no one else around of course. It's the true reason they build roundy rounds.

[giantkiller]

I believe the stock springs were around 780lbs. On the Honda shock.

[giantkiller]

If I remember right I had less than $200 into a very low mileage take off shock the spring and the compression tool. Like I said it's been a while. Probably cost more than that for the spring and tool now.

[Modo]

Heh, I've always thought those were drift circles too. 
The F4i is a pretty good shock. Had a Superhawk with the most miserable shock Honda ever used and replaced it with the F4i. Made it much nicer.