KLR Engine Top End Failure

I recently had a customer call about getting a new piston for his 2007 KLR650. During the
discussion I asked what had happened and he told me that the piston seized. That
usually happens when the engine overheats due to lack of oil. He continued that when he
pulled the clutch cover and checked the oil screen it was clogged with what looked like
case sealant and it had stopped the flow of oil – boom goes the piston.

To check the oil screen requires that you remove the water pump, including the
mechanical seal and an oil seal. A riding friend took his bike to a shop to have the screen
cleaned and some other work done for an upcoming ride because he just didn’t have time
to do it himself. Sometime after returning from the ride his bike made a clunking sound
and quit running. After taking things apart we found that water had gotten into the engine
and we all know what water in an engine can do and it did. The culprit turned out to be
the mechanical seal in the water pump that was improperly installed and the engine was
too destroyed to rebuild. That bike became a parts bike.   A simple error at the shop (by
trained mechanics?) put our friend out of a motorcycle for some time until he found
another one.

So, if you don’t clean the screen you can blow the engine from lack of oil. If you clean the
screen and don’t install the mechanical seal properly. you can blow the engine from water
getting into the engine. If you take it to a shop you can still blow the engine if they make
the same error. If you can prove they made an error, then they’re on the hook.

Any route you take can have a bad result, so be careful. Do nothing and same result.

The KLR650 has never been a high quality, artfully assembled motorcycle to say the
least, but since it moved out of Japan it appears to have trended downward with poorer
fitment on some body parts and a couple of internal engine problems. We reported a long
time ago that Kawasaki is now using an inferior grade of case sealant that has created
numerous problems.

The white sealant that is used between the crankcase halves does not stay put. Sealant
that squeezes inward when the cases are mated, breaks down and gets picked up by the
oil screen. We previously warned people about this problem and recommended the clutch
cover be pulled and the oil screen cleaned. We had one customer call and thank us for
saving his engine. His screen was almost completely plugged. He cleaned it again on our
recommendation 15,000 miles later and there was more goo, but not much. If you don’t
want to remove the clutch cover, at least check your oil pressure per the manual.

We recently found a 2006 KLR650 that had gray colored case sealant. We don’t know at
this time if the gray sealant is improved.

Famous KLR650

There’s probably no other KLR650 out there that carries such an interesting past then
the one now in the hands of Elden Carl. This KLR was formerly the property of the late
Jake Jakeman who was famous for producing the first aftermarket balancer lever (he
named it “doohickey”).   Elden has an old Dual Sport News article showing Jake’s 1988
KLR650 as he set it up around 1990. The great thing is that the bike still had all the racks
and things Jake put on it when we took possession of it in 2006.

After Jake passed away another person with an interesting past ended up buying it. Tore
Bonanno of Phoenix purchased it and didn’t really know much about Jake, but Tore’s
family name is very well known. Yes, Tore Bonanno is the great grandson of Joe
Bonanno, Mafia Crime Boss. Tore’s father Salvatore Bonanno was second in charge of
the family and ran things when Joe was in jail and after he died. One good thing that
Salvatore did for his family was not to let his two boys get involved in any Mafia business.
Both boys became successful businessman and never had any dealings with “the family”

Tore and some friends were going to Baja on KLRs and a street legal quad and needed
a place to park their rigs. He offered me a deal I couldn’t refuse and they parked at my
place. They followed me to La Fogata Restaurant in Tecate, Mexico where we met Elden
for breakfast before they headed south for a few days. The 1988 KLR650 was the oldest
bike and had very high mileage (188,000) but did manage to make it to San Quintin, Baja
before giving out. The cause turned out to be a bad mechanical seal and its adjoining oil
seal. Coolant got into the engine eventually causing it to stop running. Sound familiar?

Tore towed the bike to area 51 1/2 (our personal hideaway) for Elden to see if it was
fixable. It wasn’t worth what it would take to fix it so I bought it for parts. I later realized that
the bike just had too much history to breakup into parts, so Elden bought it with thoughts
of using another engine and leave the rest as is.  

We haven’t really gotten started on that project yet but when we do – the Jake/Bonanno
bike will retain most of the original parts. R.I.P. Jake.

KLR650 Cam Chain Tensioner

Like 99% of KLR owners you probably pay little to no attention to the cam chain
tensioner.   Yes, it keeps the proper tension on the cam chain so that the bike runs at its
best and the chain doesn’t flop around inside the cases.

The tensioner unit is located at the upper rear left side of the engine. It’s held to the
engine with two bolts and has what looks like a bolt on the end (it’s a cap). This cap
pushes on a spring that pushes on an adjuster arm (shaped like an “L” lying down). That
arm is what pushes the hard rubber thing (slipper) against the cam chain to hold the
correct chain tension.

Sometimes the arm can stick a little and not push the slipper properly and after a while
you start hearing noise; that’s the cam chain running too loose. Here’s how to fix it.
Remove that bolt looking cap, but be careful, there is that spring behind it. With cap and
spring removed, use any suitable metal object about the size of a pencil and gently push
it into the opening.  It will contact the “L” shaped adjustment arm and you will hopefully
hear a click when it has moved forward.  Replace the spring and cap bolt and it should be

If this problem occurs it would happen when the bike has 20,000 miles or so, usually. You
don’t need to do the above manual adjustment unless you start hearing excessive noise
from the left side of the engine where the cam chain is located.

If you want to see a blow up picture of the adjuster just go online and put in “2005
KLR650 Parts Fiche” (it can be any year).  A number of choices come up to pick from but
I like using the Ron Ayers site (www.ronayers.com). When the page opens, all the bike
areas are listed on the left side. Go to “Camshaft(s)/Tensioner”. (Click here to view  the
2007 Camshaft(s)/Tensioner diagram.)

Shock Spring

If you ever wonder how much a proper shock spring is needed on every KLR650, read
on. Kawasaki has been using the same rate spring on their shocks since 1987. They
must have lines of warehouses full of those wimpy 5.1kg springs and plan on installing
every one of them until they’re all gone.

Customer Comment: Just wanted to say THANK YOU for the improvement on my KLR.  I
had a chance to play with the bike off road for the first time since I changed the spring
and the difference was huge!!! And I took my son to school today with it and it handled
his additional weight great. Now on to the front suspension!!!

Thanks for the great product and fast service!!

Gary S.

We never get tired of hearing these comments. Keep them coming whether positive or

We often get customer questions on which spring is right for them. Our answer is always
the same. “We use total load weight that’s on the bike ALL the time.  That’s you with
normal riding gear and any other added weight like boxes, bags, bars, guards, braces,
tools etc.”  The key phrase is “ALL” the time”. Suspension has to be set-up for the total
load weight that would be on the bike as if you rode it every day. To include a once in a
while passenger or camping gear will end up putting you on a spring that’s way too hard
for normal riding.

Our spring rates are with preload on number one setting for the starting total load weight
and the other four settings can be used with extra loads up to the maximum of the spring
rate you are using. Example:  If your normal running around total load weight is 215lbs
using the 6.6kg spring and you add more (temporary) weight up to 230 – 235 lbs, the
preload may be on #4 or #5 preload setting. The worst thing you can do is to put on a
spring that’s too stiff for your normal riding because you’re thinking you may have a
passenger a few times a year. Sorry, one spring just can’t fit all load situations.

There are two ideal situations. 1. Have an extra spring to handle heavier loads and be
able to change the spring easily when needed. 2. Have a second shock with the heavier
spring installed.    Neither of which are practical solutions for most riders. Oh well!!
(Todd’s Note – All is not lost! If your normal riding dictates, for example, a 6.6 kg spring,
you can handle the occasional passenger or extra heavy load if you keep in mind you will
have a lower ride-height. That’s not all bad – if you are sagging more in the rear than up
front you will slightly increase your rake and trail which will make the bike more stable –
not a bad thing when you are heavy. But again, remember that you will be further in the
stroke due to the extra weight and ride with appropriate care.)