by Elden Carl
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KLR650's Forgotten Bearings & 3 Tiny 0-rings
It has long been obvious to me that the all important periodic maintenance chart in the
factory service manual is ignored by most KLR650 and DR650owners.
I recently asked a long-time rider of the KLR650-A when he had last lubed his swingarm
and Unitrak lever bearings. His answer should have shocked me but didn't. Not in over
30,000 miles had he lubed the nine rear suspension bearings.
The problem is that lubing steering and suspension bearings is a pain in the a--, so most
people just ignore them. Even worse, some service them poorly at long intervals with low
pressure lubricants like water proof grease. The choice is either take care of the
bearings or replace them which is a "real" pain in the a--. The rear suspension bearings
in Pauline's 1993 125,000 mile KL-A are original and in great shape, but they have been
repacked more than a dozen times since we purchased the bike new in 1993 from House
of Motorcycles (619 229-7700).
The choice is simple, either take care of your bikes suspension and steering bearings or
replace them prematurely.
A good example of things missed during maintenance are three tiny o-rings: Two are
found in the left cam caps sealing the oil pipe and one is found in the water pump
The two in the cam caps are subject to lots of heat and over time shrink, dry out and may
even crack, degrading the seal. I replace them every other valve clearance check.
The water pump impeller also has a tiny inside o-ring that should be changed each time
the impeller is removed. To keep the threads on the shaft from tearing the o-ring upon
removal or installation, turn left and pull gently to remove the impeller and right to re-
install it following the threads on the end of the impeller shaft. Before installing the
impeller, always carefully clean the two mechanical seal surfaces with clean solvent and
lube only with motorcycle 50/50 coolant (Honda has the best). Also put coolant on the
threads before gently screwing and pushing the impeller back into its position on the
Be careful in the water pump/mechanical seal area (follow the service manual).
Don't be like a good friend of ours who lost his engine when a local shop mechanic lubed
his water pump mechanical seal parts with grease, causing him to lose his engine less
than 100 miles later.
In closing, if the coolant in your catch tank starts turning oily or you discover coolant is
getting into your oil, quickly R&R your water pump with:
- A new oil seal
- A new mechanical seal
- Don't forget that tiny impeller internal o-ring
By all means follow the instructions in your service manual and purge the oil from your
top end, radiator and catch tank. Good luck.