Project 2smoke a 73 GT750 getting a few "updates"

[Weirdbeard1000]

I've been thinking about what to do for rear shocks. I thought about mono-shocking the rear but I don't want to relocate all of the electrics and battery. There's plenty of Chinese made throwaway shocks on eBay but I want something different, something a little higher end. Then I remembered the Fox air shocks they used to run in the 70's 80's on dirtbikes. That led me to finding these on eBay.



http://www.ebay.com/itm/200984964710

What do you guys think of this idea? They're a little long but I'm not completely opposed to that as the steering head angle is layed back like an old Swedish chopper compared to what I'm used to coming from the sport bike world primarily. Plus with the adjustability I could run a little more sag to achieve proper level geometry, and with a little shot of air I could easily compensate for loaded saddle bags, or passengers. Hmmmmmm....

[Weirdbeard1000]

Good productive day today... Didn't get to do much all week I was really busy, it was nice to get back to it. I started the day at my workplace making all the spacers I needed to get the swing arm fitted and narrowed the pivot a heavy 5mm split between the two sides. Then I went to my workshop to see if I got it right. Well, I pretty much nailed it! The only unforeseen problem I had was clearance between the back of the engine case and the leading edge of the swingarm pivot. A little hand filing on both parts netted me about 1.5mm clearance. I wish it was more but I'm afraid to go any deeper on either part.

The next step is to make some nice shock mounts and sort out spacer lengths to center both wheels. I might hang late at work tomorrow to try and whip up some shock mounts out of 1/4" aluminum.

I'm still thinking about those fox float shocks I mentioned in my last post. They're awefully expensive but that'll be the trickest thing going if they'll work.

Here's some pics.



All mocked together, the swingarm was a nice push fit into the frame. A few light taps with a dead blow hammer and it goes into place. If I had taken anymore material it would have been too much.







The stock exhaust definitely won't be going back on.



And with a slightly calibrated eye I'd say I'm going to need minimal offset on the front sprocket to get things all lined up nice. I would like to run a 520 chain anyone here have any input on weather or not that's a good idea?




Oh! I almost forgot... Friday the radiator guy called me and said my rad cleaned up nicely and I could pick it up anytime. Hopefully it was $100 well spent. We'll see I guess.

[Weirdbeard1000]

Back to the drawing board on the rear wheel bearings. I calculated the service life of those 42x30x7 bearings and at 100 mph if I only had one supporting the weight of the bike with me on it, it would last 9 hrs. I'm not sure how to calculate for multiple bearings sharing the load, but 9 hrs seems like a good reason to abandon that train of thought and look at making an axle to work with the 25mm ID factory bearings. I did find that with a few mods to the hub I could conceivably fit 7 of those small bearings in there. 4 on the drive side and 3 on the brake side. There would be no seals though with that arrangement. I also found that the small bearings I got are intended for a bicycle bottom bracket.

On other fronts, I got my shock mounts finished. They just need to be welded to the swinger (I can do a lot of things, but I can't weld for crap). I also got the bars mounted, it actually looks like a bike again! Haha. Also threw the TL wheels on so I could move it around. I have to pull it off the lift so I can tune up my friends BMW 75/6 so at least he has something to ride this season!

I gotta say, it looks pretty effin cool with the mags. But it's gonna be even more work than getting the spokes to fit, to get the chain to line up on that monster rear wheel. Plus this whole project pretty much began so I had something to use those Aprilia wheels on.

[Suzukidave]

Nice progress .. is the disk brake assembly still going to fit in there with the swingarm upside down ?

[Weirdbeard1000]

Nice progress .. is the disk brake assembly still going to fit in there with the swingarm upside down ?

Thanks Dave. The swinger is on the right way, it's a TL arm not GSXR. Whats your take on those fox float shocks? Should I just buy a pair of the Chinese remote resiviors and be done with it or pony up for the fox's. Or can you reccomend shocks that aren't Chinese made and don't look like Harley parts?

[Suzukidave]

Oop's .. i am not used to seeing a TL swingarm , myself .. i really like the look of those shocks with the piggy back reservoirs . The way lots of them have the gold bits it seems to be just a bit of cool bling

[pearljam724]

You may like these shocks. I love em. You can adjust sag by the spring collar, rebound and compression via the air piggyback shock and the eye that attaches to the swingarm rotates in or out to allow a 1/2 more or less ride height beyond the sag you preset with the springs. I paid a little more than $100 on Ebay and love how the bike handles now. This isn't the size I bought. I had to measure the sag with my stock shocks and estimated the new shocks length to add an extra inch of ride height. Good quality. http://www.ebay.com/itm/15-75-400mm-Pai ... 49&vxp=mtr" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

[Weirdbeard1000]

Those are nice for the money, but I found a set of KYB's from a Kaw ZRX on eBay. A bit more money but they have compression and rebound clickers as well as preload adjustability. I might go that route. I really like the ability to dial the Suspention in. The Fox Floats are really trick but they are $700+ and, as a friend pointed out today, if I were to lose a seal out on the road I'm kinda screwed. Definitely gonna stay with something with coils for that reason alone. Haha maybe I should mount the TL rotary damper on one side and the spring unit on the other! Lol. That'd be "different!"

[jeff kushner]

I had to view your thread on my phone to see the pics (geez, was that radiator EVER cleaned b4 you got it?) and I really like the look. I recently read some testing that was done on those 89 dollar reservoir shocks and the tester found no quality control when it came to the assembly or air pressures. He had to re-machine one of the two that he had bought because the piston had seized in the cylinder. I can search the article but I'm sure that you can find it just as easily. I like the idea of repurposing sled or atv shocks but you're right, 700 bones is a lot for a unknown quantity (if they will really work or not). You might want to call someone like Progressive just to bounce ideas. These guys make some nice looking stuff too but it might just be for bicycles!

https://www.canecreek.com/" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Or Koni with controller...just add springs:

http://www.ebay.com/itm/Koni-Adjustable ... ee&vxp=mtr" onclick="window.open(this.href);return false;

Or standard:

http://www.ebay.com/itm/KONI-14-25-SHOC ... 3b&vxp=mtr" onclick="window.open(this.href);return false;


jeff

[pearljam724]

For the love of God. Tell me you're gonna paint that thing.

[Suzukidave]

Looks like lots of color choices http://www.ebay.com/sch/i.html?_from=R4 ... c=50&rt=nc" onclick="window.open(this.href);return false;

[Weirdbeard1000]

For the love of God. Tell me you're gonna paint that thing.

Oh it's gonna get painted!!! Not sure what color yet but it's gonna be sparkley. I like the 73 gold with dark green stripes a lot but I want black stripes instead of green. But my mind keeps coming up with images of deep metal flake in some weird color and gold leaf racing numbers on the sides of the tank.

Paint is a long way off though. Haha.

[Weirdbeard1000]

Or Koni with controller...just add springs:

http://www.ebay.com/itm/Koni-Adjustable ... ee&vxp=mtr" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;




jeff

Those koni's with the controller are COOOOOOOLLLL! Too bad they're for cars. I imagine the calving would be way off for a lowly motorcycle.

[tz375]

Got to love spell check

[Weirdbeard1000]

Got to love spell check

Stupid auto correct!