FZ750 Modifications
| EXUP Swing arm into 1986 FZ750 (English model) Really easy. Even I can do it myself, apart from making up spacers. What you need is basically the complete back end from an EXUP, any model from 89-92 (not sure how easily the RU arm goes in) will fit. You want all the linkage and shock as well, though you might want to replace the shock, depends how good the standard shock is. Where the old linkage used to be, and the mounts for the centre stand are (if you had them to begin with) remove the metal that would hold the centre stand so you only have the mounting points for the old suspension linkage. Then you need some more spacers. 5mm wide, 12mm internal diameter and 20mm external diameter, you'll need two of these. Then have the bush in the linkage (the wide end of the linkage fits into the swing arm) machined out to the same size as the original linkage bolt (12mm?). Then this should fit up onto the bottom of the frame. Now, to fit the swing arm in, you'll need firstly, an engineering company who have a good reputation for quality and accuracy, and then they'll need to make some inserts to go into the EXUP swing arm bush (the one through the very front of the arm). When I had mine made I was advised to use bronze for this, as steel will rust in after a period, but you may have other requirements. Get the to machine an insert to take the diameter of the hole from the EXUP size down to the FZ spindle size, 16mm diameter. Then have them make up a pair of spacing washers, 16mm (FZ swing arm spindle size again) inner diameter, 40mm outer diameter and 1.75mm thick. Once the spindle is tightened this should clamp the swing arm nicely. The bush in the shock may need machining to open the diameter up to make it the same as the bolt for the FZ top shock mount. For the lower shock mount, standard EXUP bolt and nut will do the job, as there are no modifications here. Now my machine, by a quirk of fate, used to sit really low. It had around three inches of ground clearance BEFORE I parked my lardy ass on top of it. The EXUP linkage fitted straight in, more or less, and I found another bonus. With a friend holding the back up (thanks Gary) I fitted the EXUP dog-bones WHICH WERE THE RIGHT LENGTH!!! They are Standard EXUP, they gave another three inches in ride height at the back, which I compensated for by pulling my forks up (the front was dropped as well). I am heavier than the average bear, but still the back end is a little hard at lower road speeds. Above 70mph its beautiful, loads of feedback and a compliant ride. My shock is a Hagon aftermarket affair, and the preload is wound to half way, so taking off half inch of preload would maybe abate some of the lower speed discomfort. If you've got money to chuck at it, I would recommend a top spec shock and more importantly a lighter wheel. The EXUP rim on it's own is heavier than the swing-arm. But that is basically it. For gearing I went with standard EXUP but in a 530-chain size, as the EXUP gearing suits the 17inch rim whereas the Genesis wouldn't be ideal, but I have also got the thousand motor in it, not the 750. EXUP gearing on the 750 would be ridiculously tall. The Thousand Motor. As all of us get bored sometime with our bikes, or we want a bit more poke, the conversion to slot an FZR1000 Genesis motor in the FZ reared its head. Now I had heard and confirmed with Tony Tice (hello Tony!!!) that the motors just slot in and out. So without further ado I purchased a 1987 motor with 12000mls on it from a helpful breaker in the UK. It came with carbs, airbox, CDI, coils. I had to source an exhaust as well, which needed repairing (thanks to Dave @Simply Stainless here on the Isle of Man). Everything assembled; it was time to take the old motor out. Now, I have been messing around mechanically with bikes for about 7 years, and still I had a hard time getting the motor out. Much pulling, pushing and wrenching around eventually got it out. After the 750 motor was laying on the floor, I realised that if I had loosened the swing-arm spindle a little, the motor would've dropped straight out. Bugger. Still, in went the thousand motor, on went the carbs, airbox, exhaust, Cdi, the lot. The CDI required a couple of wires in the block connector to be swapped around, and after this, the 1000 motor fired up and ran. The only trauma was fitting the oil cooler, as I needed brackets making up. I left the gearing as standard 750 for the time being, and rode it around until it came apart during the winter for the swing-arm mods. To give you some idea of the performance difference, I had, flat out, on the 750 motor, attained 154mph on the clock, tucked in behind the screen. With the 1000 motor, I had 150mph, up hill, into a headwind, in fourth. With one more gear to go! Mental. The Six pot brakes. As a direct result of the motor upgrade, I felt that bigger brakes would be a good idea. It had a pair of twin pot AP Racing callipers, but I wanted more. After using Partsearch here in the UK, I was offered a pair of six pot callipers, lines and master cylinder from a 2000 Kawasaki ZX6R for 100 plus postage. Then I created some templates for the brackets to be based on. Basically, what I did was took the front end out of the bike and laid it on the floor, then put the callipers on the discs and made sure there was clearance between the disc and the calliper. Then I cut out a bracket with cardboard and 'fitted' the calliper to the fork legs with it. Then I took the template and the front end to an engineering firm who made the brackets. Now I have these brakes, I can do really good stoppies, though I think I have bent my oil cooler a little by doing it. The braking performance is better than that provided by normal Yamaha four pot callipers (though I can't vouch the are better than R1/ThunderAce callipers, but I bet they are!) more bite, power and feel. On the mountain (Isle of Man again) I have managed to make them fade, so I think I need new pads (original Kawasaki pads in it!). Still, the improvement is massive. Any questions drop me a mail. (c) Chris Hall - #13 |