4 of 9
STEERING HEAD BEARINGS
- The 650, like about every Japanese bike of this vintage, has an
upper and lower head bearing that uses uncaged balls. Since they have a very small bearing
surface, they are prone to impact damage. What can happen is that the balls will make little dents
in the race. Whenever the front forks are turned and the balls roll in and out of the dents, the front
end will have a "notch" or spot where it seems to tighten up. This is a very dangerous situation
since it is disconcerting and can make it difficult to do quick maneuvers.
A way to check the bearings is to sit on the bike while it is on the centerstand and scoot back on
the seat until you have taken most of the weight off the front end. Then turn the handlebars slowly
from lock to lock. There should be absolutely no evidence of binding or grabbing anywhere in the
arc. If there is a problem with the bearings, the only solution is to replace them. It’s a time
consuming job, but as long as you are doing it, use tapered roller bearings. These will run about
$50 per set, but are well worth the cost. The handling of the bike will be dramatically improved.
SWING ARM BEARINGS
- Factory original swing arm bearings in the XS650 were plastic. Not a
bad thing, as long as they are frequently greased, but few people do. The best way to check the
bearings is to put the bike on the centerstand. Have someone hold the bike while you grab the
rear wheel and push/pull from side to side. Look at the rear swing arm assembly and at the rear
axle area. When you are pushing and pulling, there should be no detectable movement in either
the swing arm pivot area or the rear wheel bearings. Any movement in these areas will cause the
bike to feel like it has a hinge in the middle and will tend to wander. Something that must be
remedied. Rear wheel bearings run about $15 and swing arm bearings are $50 (for bronze
bushings, which are recommended). The pivot bolt and outer bushing can also be worn, which
will be another $25 to $35.
FRONT WHEEL BEARINGS
- Any easy check is to have your friend sit on the bike and hold the
handlebars straight. You can then grab the front wheel and push it back and forth while observing
the movement at the axle. If you can see any movement, it is time to replace bearings.
FORK SEALS
- If the fork seals are blown, the seller will probably have wiped down the forks so
you won’t be able to see the oil residue anyway. If the forks show a very light ring of dirt about
three inches above the fork boots, that is a good sign. There will always be a little oil that gets
past the seals and is not a problem. If you can see the marks where the fork travel stopped, that
means they have not been wiped down and are in good condition. If they are very clean, pop off a
fork boot and look around the inside for a pool of oil. If the tops of the sliders are filled with oil, the
seals are gone and must be replaced. The seals will run about $30, not including labor..
ACCESSORIES
- In its day there were quite a few aftermarket and Yamaha factory items
available for the 650. Nothing like today, but still, listed below is a list of common items:
Highway bars.
Case guards.
Windshield.
Faring.
Saddlebags.
Sissy Bar (high and low)
King and Queen seat.
Luggage rack.
Luggage rack/Seat combination
Fork brace.
