First, you'll need some tools as shown in the photo above. Various screwdrivers to remove the quick fasteners, two sizes of allen wrenches (I use a speed handle), sockets for the gastank (10mm), the T-bar (14mm) and the spark plugs (5/8" or 16mm magnetic spark plug socket), an 8" extension for the plug socket, a feeler guage, a ratchet, and a torque wrench. You may also need something like the needle-nosed vice grips to pull the plug wire caps.
The first step is to pull the little black side panels at the lower rear of the gastank. Then remove the two bolts shown in the photo above with a 10mm deep socket. An extension is useful here.
I use the 4" stubby ratchet for all the 10mm and smaller nuts and bolts, as that way I can't put apply much torque them when replacing them and strip them out. With the standard long handled ratchet that's fairly easy to do if you aren't careful.
Rather than removing the gastank, as the SERVICE MANUAL suggests, I prefer to shortcut by blocking it up with a short piece of wood. A 9" or 10" piece of scrap 2x4 or plywood works great. One enterprising guy just wrapped duct tape around an old thick book and used that. I find blocking up the front of the tank this way gives me enough room to change the plugs or sync the throttle bodies, and saves me some time.
You do have to remove the T-bar to get to the spark plugs. First, you have to remove these long blue loctite'd screws that hold some rubber bits in place. Seems like overkill to me.
Then use the 14mm to remove the 3 large bolts holding the T-bar on. They are pretty tight. Notice in the fuzzy photo above (and the sharper one below) that I left the 2 screws in place that hold the molded rubber pieces. That way, they're harder to lose.
This is the T-bar.
To change the plugs, first blow off the top of the engine with compressed air to get rid of the loose dirt, bugs, etc. Then pull the plug caps. They are quite long, and can be hard to remove due to the tight quarters. I got a couple of them with my fingers, but had to use some needle nosed vice grips for the other two.
Use more comressed air to clean out the spark plug wells before you remove the plugs. I used an 8" three-eights drive "wobble" extension and a 5/8" magnetic spark plug socket. The wobble extension allows the socket about 16 degrees of movement. This is very handy as it is hard to get a straight shot at the plugs.
Torque the plugs to 13 Nm (9 ft-lbs) as shown in the photo above.
You might as well do the throttle body sync now too, as you've already done 90% of the work for that service item (getting to the sync nipples).
The T-bar goes back on with lots of torque: 78 Nm, or 56 ft-lbs, but only on the 3 large mounting bolts. Yamaha obviously wants it to stay put!
Putting the bike back into riding configuration is left as an exercise for the reader...
Copyright © 2002, by H. Marc Lewis. All rights reserved.