Fork and suspension Lowering 1990 K 75S Questions

[The Mighty Gryphon]

You can get about 10mm by raising the forks in the triple clamps, and about a half inch by putting a shorter shock at the rear. 

You might need to modify the center stand as a lower bike needs to be raised that much more to get it on the stand.  Remember, you are lifting about 550 pounds even if it is less than a half inch. 

[Laitch]

So to lower a K75 RT, with fairings removed, sounds like springs in the back and a fork adjustment would do the trick. Combine that with a lowered seat setup and maybe shaving the seat a bit… would y’all say that’s the best way to lower the bike without sacrificing the handling? And running lower profile tires?

What you need to do depends upon how low you need the Brick to be. Removing the OEM standard height seat and installing an OEM low seat and its assembly will lower seat height by 2 inches.

[tweather]

Everything I’ve read here and elsewhere… total drop from standard is about 3 inches all things combined. Does that sound right? Glad I’m doing this math now because I’m not sure this would be low enough to get my partner’s feet on the ground. 🙃🫠

[Laitch]

The 2" lower seat height gained by installing the OEM low seat and its assembly applies only to the rider, not the passenger. That seat has a V-profile into which the rider nests; the passenger's seat is not lowered as much. At least one member here has added lifts to his boots. In addition to cutting down and narrowing the seat profile, raising the tubes in the fork, and using a shorter shock, that did the trick for him. Perhaps the passenger should consider having boots customized with thicker soles and heels.

[tweather]

I meant as rider, not passenger.

[Laitch]

I meant as rider, not passenger.

If the lowering you've calculated isn't enough, carving more from the seat and modifying the riding boots are what is left without greatly compromising handling and ground clearance.

[Martin]

Boots with thicker heels help but you can also add shoe lifts. However you might have to go up a size in boots. Buy the lifts first and take them with you when buying the boots and try them out for fit. I have a 1" shorter YSS rear shock and have dropped the forks through the trees. After doing this I bought a straight leg stand and shortened it by cutting out a piece but I also made up plugs to reinforce the weld. I also had to modify the side stand by bending it a bit more to get the lean angle right. I used a butane torch and a 3/4" pipe bender bending  slightly letting it cool and trying it until the correct lean was achieved.This led to further modifications on the stand foot to stop it scrapping. And this led to the stand buffer having to be modified to accept the side stand. Done right all this should not compromise your handling, however very occasionally when at extreme lean angles it may scape. The bike has also been fitted with a Corbin seat which may be slightly lower.

Regards Martin.