AUTO
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Chapter I: Engine Rebuild 98/07/01In the summer of 97 I picked up a fairly decent (running) 1979 Yamaha RD400F Daytona Special. This motorcycle is the re-styled and slightly hot-rodded version of the '78 RD400E, and the precursor to the liquid-cooled RD350, which was the precursor to the popular RZ350, which was the precursor to the...nothing in North America. Damn those emissions regulations... This particular unit came with DG Performance pipes (peaky, and not terribly attractive, though better than stock), Tommaselli clip-ons (nice), and homemade rearsets that placed the footpegs almost five inches above the stock location. Needless to say, the first thing I did was pick up a set of stock footpegs...
After a few months one of the pistons desintegrated. I suspect the piston skirt got hung up on one of the ports, possibly due to worn con-rod bearings allowing for piston play. A rebuild was obviously necessary at this point, and the living room coffee table seemed as good a location as any to perform it. The rebuild was not nearly as difficult as I had anticipated. At first, I was inclined to have a shop perform the entire exercise, but in the end the only thing that was not done by myself was the crank rebuild, which is a very difficult and specialized process that even the shops farm out to specialized machinists anyway. In terms of special tools, the ones I did not already have in my arsernal included a torque wrench (very useful for a variety of jobs, $70), several large sized sockets (for the countershaft sprocket, clutch and crank), an impact driver (everyone should have one of these, $30), a special puller for the ignition (not required for pre-1979 RD400s), and a Haynes manual. The last item on this list is probably best used in conjunction with the factory Yamaha shop manual. The only reasons why I did not utilize the factory manual were lack of funds and a very experienced friend a phone call away. Otherwise, a good socket set, a few box wrenches, and some quality allen wrenches and phillips screwdrivers is about all that is needed for an aircooled RD rebuild. That is, except for a small mountain of seals, gaskets bearings, rings, etc, etc. The Haynes and Yamaha manuals will tell you what should be replaced, and a good Yamaha dealer will aid in sourcing those parts. Make sure your Yamaha dealer has the microfiches for your particular bike, as this can help speed up the process dramatically. A patient parts counter person is also a bonus. If you plan on working on an old bike like this, you get to know the parts counter people quite a bit. The original shop I went to for parts had a gentleman with the worst attitude when it came to fixing up old bikes, and grudgingly looked up parts for me while muttering how it would be much better to buy a new bike. Needless to say, I did not order part one from him and never returned to that particular shop. Luckily, I found a shop that was both closer to home, and had far friendlier staff as well. So it pays to shop around if you feel you are not getting adequate service! There are a couple of steps of the rebuild that are far easier with a second person, such as the obvious removing and reinstalling of the engine in the frame without scratching the paint on the frame, carrying the engine up two flights of stairs to your apartment (no elevator or garage to work in), and dropping the cylinders onto the pistons without a ring compressor. The only parts of the rebuild that strike me as being difficult were getting the clutch center, primary drive (crank) and countershaft sprocket nuts off. The Haynes manual has a few tips for these, but in the end it seems a lot of leverage and strength prevail. Nothing is more satisfying than hearing the engine start for the first time after a rebuild. Nothing, maybe, except riding your newly rebuilt (and broken in) bike on one of the most beautiful and challenging highways in Canada, the Sea to Sky from Vancouver to Whistler. Quite a rush!
A move to a new location, however, and the subsequent lack of storage space meant storing the rebuilt beast at a friend's garage. For this reason, the bike has sat dormant, uninsured and unlicensed. The current plan is to do a complete restoration, although not to exact stock specs. The frame, now red, will be repainted to the orignial black colour, as will the yellow wheels. The forks will undergo a similar process. The rear brake master cylinder will be rebuilt, and the swingarm will receive bronze bushings. The steering head will receive a compliment of tapered roller bearings, and the forks will get new seals and oil. The plan also calls for a set of Spec II or Pro Flo pipes(although I am not sure if Pro Flo has RD400F pipes available at this time, so it will likely be Spec II). With the new pipes will come a complete process of carb cleaning and jetting (something that should have been part of the first rebuild but was neglected due mostly to impatience). The front fender, tank, sidepanels and tailsection will receive new paint, as well as new stickers.
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