Author Topic: Gs500 katana front end 1998+ lower triple clamp  (Read 58 times)

Offline nick_berg

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Gs500 katana front end 1998+ lower triple clamp
« on: April 17, 2019, 04:07:19 PM »
Hello everyone,

I am currently trying to replace my stock gs500 front end with a katana front end from the 1988-1997 model. The steering stem on those models are all welded in and I did not like the idea of grinding away the weld. I was wondering if the 1998+ model lower triple clamps have the same diameter steering stem, I know the gs500 has a 30,15 mm steering stem where it presses into the clamp. Also, I was wondering if the 1998+ front wheel would fit the 1988-1997 model front forks without having to create custom spacers.
Any help would be greatly appreciated. Also, I would like to thank everyone on this forum for all the very useful information on working on my gs500.

Offline The Buddha

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Re: Gs500 katana front end 1998+ lower triple clamp
« Reply #1 on: April 19, 2019, 04:06:46 PM »
I have swapped in the later ones as well.

We don't grind the weld out (unless you want to).
OK so there are 2-3 ways of doing it.

Grind out GS stem if its not pressed in, grind out kat stem, put GS stem the kat lower triple is thinner than the GS triple, so it leaves a nice bit of meat below the triple. The artist around here - Werase643 put it al together, and made like 12 or 16 short cuts in the stem that's overhanging, and flared them out and welded up the cuts which were now like a V. Insane cool work.
Obviously this method has some massive benefits - the thing will give you useable steering lock - a total necessity IMHO in my hood. I think you need to use the GS top triple center nut, don't immediately recall if kat is the same, and I am nearly sure the thread boss is smaller than the kat's upper triple, you may need to fit a sleeve bushing there, you really must have a tight fit there.

If you don't want to do that above grind and weld - you machine the top to take the upper bearing about 3/4" lower. Then you machine up 2 spacers one with the dust cover relief and one without to go on top of and under the adjuster nut.

This leaves you with a steering lock that's not gonna work, and the ignition key needs to go in a 1/2" deeper hole etc etc. This was invented by our other resident artist Dgyver.

I have done a weird combo of 2-3 methods. And this is my method.
Machine the top of the stem to take the bearing lower, then thread the thing to take the lock nut lower. Then cut and grind out the top thread boss. Then put it back in the top of the stem and weld it. That is the only welding you need to do.
The lock fits and works, the key cylinder is flush with the triple.
The big reason I came up with this - I don't have a lathe lying around. I have a vice, grinder etc and a welder. The machining of the upper triple bearing area can be done with a super soft high grit wheel on an angle grinder, especially if you have a helper and a vice.

I also made a fitting to fit the gauges onto the katana triple using existing bolt holes for the clip on and they take the stock guage grommets.
I made long ears to fit the headlight on and I would spread the stock ears where they go in the forks and fit them on with the stock grommets. Need longer headlight ears cos you have moved the gauges forward a 1/2-3/4" and that wont let the tach cable fit without hitting the back of the headlight bucket.

As a result people see - nothing. They think its stock. Even people who own GS'es ask me how I have a twin disk FE. And that is the whole goal.

Any time some fool says "turns heads" on a craigslist ad - its pretty much a sign that he has lost the game before it even started. Maybe it turns heads cos "people are going WTF is that garbage" ????

Do it the way you want, but a bike that works as it left the factory should be your goal even if different parts of it left on different bikes. That way, you can say its all stock ... just from different models.

You want to turn heads - put an exhaust or some glittery stickers on it.

I run a business based on other people's junk.

Offline nick_berg

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Re: Gs500 katana front end 1998+ lower triple clamp
« Reply #2 on: April 21, 2019, 08:25:35 AM »
Thank you Buddha for your helpful write-up.
I did see Dgyver's post with the spacers he made. If Werase643 made a post I will look at that aswel.

We have a machine shop at my school wich students of educations other than engineering are allowed to use sometimes (I do electrical engineering myself). I'll ask the experts there for their opinion aswel and post pics as soon as I decide on what to do.