Major Upgrades Planned

Although currently sitting at 3,700 miles, I started to prepare for my 5,000 mile maintenance that will include a couple major upgrades to the engine on my 2016 Kawasaki KLR650. The next normal maintenance cycle provided in the Service Manual would be 7,500; however, we have a lot of conditions here in Florida that warrant acceleration of many of the routine maintenance steps such as oil changes and air filter cleaning.

The two major upgrades that I'm planning for during this maintenance cycle are the Doohickey Upgrade and the Thermo-Bob Upgrade. I'll take them one at a time.

Doohickey

I'm not sure who thought up that name (or why), but the Doohickey has been a defect of the KLR650 engine since the day it first rolled off the production line. In short, the Doohickey is a triangular lever that, together with a spring, serves as the tensioner to the counterbalance chain.

The counterbalance system and doohickey are located under the left case cover.

Under the lever is the tensioner spring to the lever.

The problems with this assembly are several. On Gen1 KLR650s the lever and the spring are actually prone to fracturing and causing a lot of problems inside the engine as broken metal parts work their way down into the sump.


While the fracturing problems were presumably cured when the Gen2 KLR650 was designed, the lever and spring continues to be seriously flawed.
The lever is too loose and wobbles causing noise and wear. It also doesn't provide the full range of tension on the chain. In fact, it only provides about 33% of the range of tension that you see in that half-moon slot.

The other issue is that the tensioner spring stretches out and becomes ineffective. That is, it's providing no tension on the counterbalance chain. The spring in the photo above was totally coil bound at 4,000 miles. There are reports by people who do the doohickey upgrade saying that their springs had sprung and were totally useless in as little as 2,500 miles.

The upgrade is to replace the tensioner lever with a good aftermarket lever (made by Eagle Manufacturing) and replace the spring with a more effective torsion-type spring. Here's a look at the two components that were designed and are manufactured by Eagle Manufacturing & Engineering (aka Eagle Mike).

When all is said and done, the tensioner will look like this...

So I've gone ahead and ordered my Doohickey Kit from Eagle Mike for my upcoming 5,000 mile service. The kit includes the two above parts, plus some special tools and replacement case gaskets. The complete kit cost $138. It's not an easy upgrade, but it's a one time fix and worth it.

Thermo-Bob

Unlike Doohickey, Thermo-Bob is actually the name of a product. However, since it's the most popular fix for this particular issue, everyone seems to call it the Thermo-Bob Upgrade or Mod.

The issue that gives rise to the Thermo-Bob upgrade to the KLR650 is found in the motorcycle's cooling system. The problem is that the KLR cannot stabilize and control the engine temperature in consistent and steady manner throughout the engine. I noticed this right out of the gate when I got my KLR. The needle was all over the place. It would drop low to the bottom of the temp gauge when riding at virtually any speed and then rise to the near the top of the range when stopped and idling for any length of time.

This wild inconsistency is due to the fact that the temperatures in different parts of the engine are controlled differently and have the tendency to work against each other in maintaining engine temperature. The temps in the upper part of the engine are controlled by the radiator and runs on the hot side. The temps in the lower part of the engine are controlled by the thermostat and run too cold. All this is largely due to a thermostat that has an excessively low temp trigger of 160 degrees and poor routing of the coolant around the engine.

This temperature imbalance is dangerous to the engine. A proper balance of temperature is necessary for both the metallic components as well as the oil temperatures as it moves through the various parts of the engine.

What is needed to correct the temperature imbalance is a mechanism for the water in the engine to keep moving throughout the engine both quickly and evenly and also circulates around the thermostat so it doesn't open...but then quickly slam shut when the cooler water from the lower end of the engine reaches it. This is what the Thermo-Bob does. It is essentially an external thermostat coupled with a coolant bypass.

The Thermo-Bob Kit from Watt-Man re-routes the water flow and moves the thermostat to provide a constant flow of water and balance of temperatures throughout the KLR650 engine. It also provides a much larger thermostat that activates at a higher (195 degree) temperature (compared to the stock 160 degree thermostat).

Here's a look at the components of the kit that cost $125. There are other options for this (and similarly influenced) upgrade, but the Thermo-Bob by Watt-Man is considered the gold standard. Watt-Matt Testing Report.

Bottom line, the KLR650's temperature problem isn't going to destroy its engine overnight...or anytime soon. In fact, I've heard people recommend the Thermo-Bob mod only if you're planning to keep your KLR more than five years. Well, I don't operate like that. If the motorcycle has a problem I'm inclined to fix things that I can fix irrespective of how long I plan to own it.

BTW...I've had dozens of motorcycles over many years and, with a very few exceptions, I planned to keep each one forever. :)

Of course I'll report back when i get these upgrades completed.