GT550 budget build

[Suzukidave]

Unless they had already been changed out the GTs came stock with roller bearings in the steering head where the GS front has taper bearings .

[JoostGT]

You'll need to check if bearing size between GS and GT are the same, otherwise (obviously) they wont fit. Now is also the best time to swap to tapered roller bearings, it'll improve the stability of your bike tremendously (yes, new ball bearings also work fine, but most GTs don't have new ball bearings anymore )

There are lists available online with bearing sizes for loads of different bikes, I ended up using XS650 bearings to fit GSXR forks in my GT. Also check out a company called "all balls" or something like it, they can supply you with a wide range of (custom) bearings.

The silver parts are indeed anti-dive, they can be problematic, but they're great when working properly. They use brake pressure to operate a plunger which diverts front fork oil through a narrower passage, making the suspension stiffen when you apply the brakes. Removing and blanking off puts the suspension permanently in the braking position and very hard! Just remove the brake hose and leave the body.

[pearljam724]

Ball bearings from any 70's Japanese bike are the same as Gt's. I used Honda CB 750 bearings.

[Coyote]

The GT and GS tapered rollers are totally different. This is because the GS has a much larger neck. I don't know what you can mix and match to make them come together right, but what you have pictured won't work.
I don't know when they changed, but my 78 GS1000 does not have tapered rollers. It has the flat races and a handful of loose balls. Also the aftermarket tapered rollers for the GS come with 2 dust covers. The aftermarket GT rollers do not have any dust covers. I converted my GT550 to tapered rollers (all balls). The assembly leaves a slight gap between the bottom of the triple tree and the neck. I filled that with a fat o-ring.

[Cragdog]

Thanks for all the input you guys, I agree the current set up will not work. I have ordered the conversion kit from all balls racing to make the GS1100 forks fit the GT550 frame with all the seals and tapered bearings to make it work. I look forward to getting that front end finished.

My next big task that I've been scratching my head over today is making the rear wheel with disk brake fit the GT's swingarm. It is close, but not quite a bolt on application... Need to figure out the best way to make it all line up properly. At the moment it's very snug and took a bit of finess to get the swingarm onto the axle. Once together I mocked it up to see where things lined up. As you can see in the pictures, the front and rear sprockets are now offset because I had to remove a spacer from the sprocket side of the axle to accommodate for the brake caliper mounting bracket on the other side of the axle. Also, the sprocket drum for the wheel with the disk is wider than the sprocket drum for the wheel with shoes, my first thought was to cut the drum down so it is the same width as the other one, then the sprocket side spacing should line up correctly.

My other thought was just to find a GS swingarm already set up for rear disk brake and fit that to the GT frame.
I'm feeling as though this rear end conversion is getting to be beyond my current abilities and depending on whether I can find someone to help me make it all fit properly I might just go back to the smaller rear wheel with shoes that the bike came with. We'll see how that one developes..

[Suzukidave]

Your best bet would be to get the swingarm to mach the disk wheel , i wish i was at my home in Florida as i have one there i could let you have .

[Cragdog]

Your best bet would be to get the swingarm to mach the disk wheel , i wish i was at my home in Florida as i have one there i could let you have .

That's a kind offer Dave, I am wondering if I buy the hub for the chain driven gs1100 like this one http://www.ebay.com/itm/Gs1100E-Gs1100- ... de&vxp=mtr if that would settle the issue and still use the GT swingarm
The GS swingarms are expensive! http://www.ebay.com/sch/i.html?_odkw=Gs ... acat=10063

[Suzukidave]

I believe your wheel would fit a GS750 swingarm http://www.ebay.com/sch/i.html?_odkw=Gs ... acat=10063" onclick="window.open(this.href);return false;

[Cragdog]

I believe your wheel would fit a GS750 swingarm http://www.ebay.com/sch/i.html?_odkw=Gs ... acat=10063" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Those look much more affordable.
Wouldn't I still be running into the problem with sprocket hub spacing though?

[Cragdog]

I fitted the smaller hub to the larger wheel and it looks like everything is lining up nicely now, the only other issue now is that the axle bolt shaft is just barely too short so I cannot fit the cotter pin through the locking nut..




The wheel is now nicely centered in the GT swingarm using the smaller hub, obviously the diameter of the hub is too small so if I can find a hub with the larger diameter (18cm), but smaller width (3.5cm) I think I'll be in business. I've asked a few feeBay sellers to measure the hubs I was looking at so hopefully one will respond and have these dimensions.

[Cragdog]

Haven't posted in a bit, but I'm waiting for a few parts to hopefully finish it off. I accidentally ordered the wrong bearings kit apparently for my front end conversion. The eBay seller wasn't able to help me much, but all balls came through and got me setup with the right kit for my swap. I would highly recommend these guys, super helpful and knowledgable, they are sending me a discounted set today!
Waiting on my replacement hub to hopefully finish off tweaking the rear axle spacing then weld the brake stay mount to the swingarm, then rear MC placement and linkage.
Finally selling my Jeep and that GS I recently picked up so that will give me a little extra cash to see this bike finalized.

[Cragdog]

New bushings installed in the swingarm. Absolutely zero play side to side now.


Also got the new tapered roller bearings from All Balls. Installed and front end back in place. Had a worry for a bit with the steering stem bolt, was really difficult to thread, but I gingerly chased the threads and it seems to be fine now.


Hopefully tackling the rear wheel this weekend. It sits too far to the left in the swingarm and is not centered. I will need to have some material machined off of either the brake caliper mount or the spacer on this side. Once I get the wheel centralized in the frame then I will focus on sprocket placement and chain alignment. I don't have the equipment to tackle these issues so I will need to outsource some help to finish of my project. I'm still shooting for the goal of riding by months end. I sure hope at least!

[Cragdog]

Oh and just to make sure everyone stays focused:

[tz375]

That wheel spacer looks rather thick. Have you tried to fit the caliper and is it central to the disk or off to one side?

[Cragdog]

That wheel spacer looks rather thick. Have you tried to fit the caliper and is it central to the disk or off to one side?

The caliper mounts just fine so I was thinking of taking material off the right side of the bracket, that would keep the caliper spaced correctly and move the whole wheel slightly right on the axle. Thanks tz