Dapper Rat Yamaha XS750 24 January 15
The 1978 Yamaha XS750 came into Matt Schindler's shop, Dapper Rat, with about 55,000 miles on it. With so many miles, a teardown and inspection was warranted. They tore down the engine and found that everything inside looked good, except the cylinders were slightly out of tolerance. This is to be expected for an air cooled bike of this age and this many miles. Due to lack of availability of oversize pistons for the 750, they bored the engine out to 850cc using the standard (not oversize) pistons for the XS850.
The engine is just part of the story. The 1978 standard XS750 forks and brakes leave a lot to be desired by modern standards (even though the bike was one of the first to have dual disks). So a front end swap was in order and they decided on a 1987 FZR1000 front end. The FZR1000 was one of the best handling bikes of the 80s, and so this would be an excellent start. The triple clamp assembly was modified slightly to allow it to fit into the XS750 frame. Due to the shaft drive, they decided to keep the stock wheels, which also keeps the period look. The brakes were converted to more modern Brembo calipers and master cylinder from a Ducati 996, the disks are EBC with a special 15mm offset.
The XS750 came from the factory in 1978 with many bells and whistles, such as self canceling turn signals and detection for burned out light bulb. Being sport bike enthusiasts, Dapper Rat felt this was overkill, so they took all the crap off and put back just the basics. Stock charging circuit, a Shorai Lithium battery. Since the stock battery box is huge, Dapper Rat fabricated a custom aluminum battery box mounted under the seat. The stock electronic ignition was kept, and they replaced the speedo and tach with a single Motogadget Chronoclassic instrument that reads both RPM and speed. The seat was replaced with a custom cafe’ racer seat. Low profile turn-signals were installed front and rear. Due to the many electrical modifications, the stock wiring harness was thrown out and a custom harness made using high-temperature chemical resistant wire, high temperature sleeving and Nomex lacing tape rather than zip ties. Lightweight Woodcraft clip-ons replaced the heavier (steel) FZR1000 bars. The engine was painted with VHT (Very High Temperature) black “barrel” paint. The frame and wheels powder coated and all wheel and steering head bearings replaced with new. The exhaust was replaced with a Mac 3-into-1 with the muffler converted to the a stainless steel reverse megaphone and the headers were wrapped for the cafe racer look.
Photos by Shell Geer
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Alan Goodsell , 24 January 15