One of the most common upgrades for the katana is the suspension. It is always nice when you can corner better and stop safer. Updating the suspension gives the katana a much meaner look and makes it safer to ride. Not only is there considerable weight savings, you have better brakes and a larger footprint holding you to the road.
If you have not seen a katana upgraded with new suspension, have a look on the customs page. I much prefer the more modern gear. It makes for a much more pleasurable riding experience.
The information on this page is for entertainment only. I am not a licensed mechanic and I am only sharing what I have done. You must make sure everything you do is safe and legal. I strongly recommend you get a professional to do any modifications effecting handling and safety.
FORKS & TRIPLES
For the Suzuki Katana, some forks work better than others. There are several considerations like fairing clearance, ground clearance, stem bearings and speedometer compatibility.
Early 1990's GSX-R forks bolt right onto your katana. 1993-95 GSX-R 750 triples even have the correct steering stops, as does the 1100's up to 1998. 1995-'97 GSX-R triples use roller bearings that would need to be replaced. You cannot mix and match top and bottom triple trees. Buy a set.
Honda 954 triples are what I use for my 1992 GSX-R forks. You need to replace the roller bearings with tapered ones that are available on eBay for cheap. Also, steering stops are needed. The bottom triple pinch bolt can contact the katana cowl frame which is a minor fix.
There are many opinions out there on what needs to be done to the Katana frame to keep it from bucking you off in a corner once you have loaded her up with new radials, better suspension, a decent swing arm and gobs of power. The reality is, if you are pushing your kat to its limits on the street, you have much more to worry about then the frame. Minor bracing and an updated swing arm will improve your experience greatly.
The rake and trail of a motorcycle is important to the stability of it at speed. If your trail number is too low, the bike becomes unstable and is prone to speed wabbles which can endanger you and others on the road.
1982 vs 1983, 750 vs 1000/1100:
The 1982 and 1983 katana frames do not share the same pegs and they are not interchangeable. The front motor mount bolts pass through the frame tubes on the 1982 katana but do not on the late 1982 and 1983 katana. The GS750 katana frames bottom motor mounts are about an inch further back than an 1100cc engine but can easily be fixed by using modified lower mounts. Other than those minor differences, the gs(x) 750s, gs(x) 1000 and gs(x) 1100 katanas are the same frame
The lower the number the faster the steering which is why modern supersport bikes have steering dampers. The katana has a lot of trail and is very stable at speed enhanced by its large front wheel and long wheel base. Shorter forks and a raised back end decreases trail so care has to be taken if you are replacing the front and back ends. Another contributor to trail is the triple tree offset. I recommend you do your research before attempting to modify your katana.
There are a couple of frame adjustments that need to be addressed when installing a B12 swing arm.
• The rear brake actuator stop pad needs to be reduced as it contacts the swing arm. The actuator itself needs modifying for clearance. Or, you can spread the peg stays 1/4" for clearance keeping in mind the travel of the brake plunger (master cylinder). I recommend losing the stock break light switch and use an inline banjo bolt/light switch off the top of the rear brake master.
Here is a katana frame bracing diagram from www.robbynitroz.nl, I have found "D" and "E" bracing is plenty of support for road riding. In this diagram the bracket for the battery has been removed. I weld in another stronger brace in its place.
BANDIT SWING ARM CONVERSION:
The nice thing about the B12 swing arm is that you don't have to cut off the peg stays to fit it unlike a GSXR swing arm. Also, no modifications are needed for the frame pivot or swing arm pivot. All that is needed is a pair of reducer bushings (available on the parts page) to fit the swing arm to the GS frame.
• If you don' t remove the mono shock mount from the swing arm you will need to move the battery cage higher in the frame which means losing the airbox.
Bracing means you lose your airbox and it is good opportunity to relocate your battery. I tuck a lithium battery up under the side covers under the rear of the tank. There is just enough room with the right battery.
It's best to swap the entire front end as mix-and-match can be a headache. As far as inverted for go or "upside down" forks, 1993 GSX-R 750 front ends fit best for the Katana. '93 are the longest but the 1994 and 1995 also work.'92-'98 GSXR 1100 forks work but contact the fairing frame and cowling requiring material removal. The GSX-R 750 forks however, are 1" shorter than the GSX-R 1100, which can be augmented by installing Honda 954 drop triples. Although the GSX-R 1100 forks are longer, the clipons are on top of the triple which uses up an inch of fork length. If you want to use the 1100 forks, you can use ZX series clipons or any other 52mm clipon. You cannot use the GSX-R handle bars as they have no pinch bolts and bolt directly into the top tipple clamp.
Newer forks are much shorter and risk high speed instability as your trail shrinks to dangerous numbers. Some
GSR-R conversion can drop ride height more than 4 inches. 3 inches plus from shorter forks and 1" from using a 17" wheel vs 19" wheel. For turbo bikes, this isn't a concern, but some headers can make road contact on right hand turns causing a crash. With GSX-R forks, 954 triples and my new Stainless Steel header, I have had no cornering issues. DO NOT jack the back of the bike up to increase ride height as this critically effects stability by decreasing your trail.
The information about motorcycle conversions on suzuki-katana.com is for entertainment purposes only. They are personal experiences. Always have motorcycle work performed by a licensed professional.