Oil Pressure Gauge Installation

By:cpmodem

It is important to know the true oil pressure of any engine, but especially true with high performance engines such as this KTM 950. Particularly given the extreme stresses many place on their beloved Katooms. The LC8 engine has been known to loose its water pump seal, resulting in water contaminating the oil, which causes the paper oil filter to swell closed. The result is gradual, but by the time the oil pressure "idiot light" indicates there is a problem, it is often too late to save the engine from undue wear or catastophic failure. An accurate oil pressure gauge will indicate the early tell-tale signs of an impending oil filter clogging. The problem can then be corrected in a timely and safe manner.

Fit is snug, but adequate in either top fairing piece. I installed this one in the right fairing. There are several other locations that are also suitable, depending on your particular needs.

There are several options for locations to tap for oil pressure. In this case, the rear cylinder cam tensioner bolt provided a handy spot in an easy to get at location. I tapped the center of the bolt with 1/8" pipe threads and drilled the center with a 3/16" inch hole to match the 3/16" stainless steel flex hose I was using for the oil line to the gauge. The bolt is easily removed from the engine so it can be drilled and tapped easily and safely.

I generally like to use aircraft quality stainless steel braided hose for applications that have to contain high pressures, flamable products, and/or the engines's life blood (oil). This is especially good practice with motorcycles. Auto Meter retails this 36" long piece of AN-3 with fittings for 1/8" pipe and even an adapter for 1/4" pipe thread for ~ $50 US.

There are several locations that are possible to tap for oil pressure on the LC8's. In this case, the rear cylinder cam tensioner bolt provided a handy spot in an easy to get at location. I tapped the center of the bolt with 1/8" pipe threads and drilled the center with a 3/16" inch hole to match the 3/16" stainless steel flex hose I was using for the oil line to the gauge. The bolt is easily removed from the engine so it can be drilled and tapped safely.

The AN-3 to 1/8" pipe fitting was installed using petroleum resistant teflon sealing tape (the yellow stuff)

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36" of AN-3 (3/16" I.D.) stainless steel braided high pressure hose was used for safety and durability. This tap in point also allows me to easily keep the OEM "idiot light" for those times when I am HUB and not watching the gauge. Some racers attach a large, bright brake light to the oil pressure switch just for those situations.

Now it is possible to know at all times what the engine's "life blood" is doing.

The factory oil pressure specification for the LC8 engines is:
Minimum of 1.5 bar (22 psi) @ 1500 rpm taken at 60 deg C (140 deg F)
As you can see, this KTM 950 has 32 psi at 1400 rpm (idle) and 100 deg C (212 deg F). Well in spec.

The factory spec also prescribes a range for oil pressure at 6000 rpm (again at 60 deg C).
3.0 - 4.0 bar (44 - 58 psi)
This image shows I have 51 psi at 6000 rpm at 100 deg C. Right in the middle of the spec.