Fork upgrade on 1989 gsxr400

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warro46
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Fork upgrade on 1989 gsxr400

Post by warro46 » Tue Dec 31, 2019 10:48 pm

I've 1989 gk73a my question is can i put later year model front end, if I had a complete forks and yokes off say 1992 would it fit, and is there a noticeable difference. Thanks

mechannibalism
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Re: Fork upgrade on 1989 gsxr400

Post by mechannibalism » Wed Jan 01, 2020 8:50 pm

There is no just bolt in and knock your socks off swap. You can buy a$180USD "emulator" that's barely noticeable or if you want to stay with RSU forks It's possible (will require machine work) to bolt in a set of '03-'04 R6 forks (43mm) They have low speed rebound damping & high speed compression damping and a mid speed damping and are probably the best RSU forks and the best bang for the buck.......or you can do what I did here> https://www.instagram.com/mechannibalism

mechannibalism
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Re: Fork upgrade on 1989 gsxr400

Post by mechannibalism » Wed Jan 01, 2020 10:47 pm

If you are set on using newer USD forks, one problem you will run into (the RG/RD500 guys have seen a lot of this) is the larger tubes and larger triples interfere with everything in the front cowling, usually the frame is now too small.

moforockband
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Re: Fork upgrade on 1989 gsxr400

Post by moforockband » Sat Jan 04, 2020 11:51 am

I made a good performance gain on my GK73 SP forks by using some ktech fork springs, and new 10wt oil on std dampers.
The forks now aren't the weak part in the chain anymore.
But the sp forks are fully adjustable, you may have the std ones?

LiteTekBlair
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Re: Fork upgrade on 1989 gsxr400

Post by LiteTekBlair » Tue Jan 14, 2020 11:59 pm

Here is an article I wrote about changing front ends. Might be useful. https://2fiftycc.com/index.php?threads/ ... orks.3046/
Carb seal kits in viton & other parts
https://litetek.co


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