Changing the FJR's Spark Plugs
The service schedule
for the North American FJRs calls for changing the
spark plugs every 8,000 miles. Here's how to do it.
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
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
Copyright © 2002, by H. Marc Lewis. All rights reserved.