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A Word About Race Fuel

Thu, 07 Jul 2011 03:30:00 +0000

Depending on your application you may be using a commercial race fuel. This has many benefits including consistencey which is not the case at the local station. Ethenol and other pump additives can cause temperature increases causing all kinds of issues with smaller higher performance engines.

Regardless of the reason you deside to run a race fuel, it is important to take a few steps to protect your engine and fuel system from the negative effects of these products; particularly those which contain oxygenators. Some fuels leave a sand like substance all over valves, seats, combustion cambers etc...

We recommend that you drain your fuel tank after each use and purge the engine for several minutes with pump gas. This will wash the entire system of potential corrosion causing compounds. To take it a step further, you can also spray a quality engine storage spray or mixture of 2-stroke oil and fuel into the intake while it is running. This only needs to be done for a few seconds per cylinder in order to fog the valves and cylinder walls.

So take the time and prolong the life and performance of your investment.

Rich

Leak Test your engine

Tue, 22 Feb 2011 04:12:00 +0000

The best way to know if your engine is in optimum condition between rebuilds is to leak test it every few races. This will alert you to problems early, and in the case of a tight valve you may be able to adjust clearance before damage to valve and or seat occur.

A problem we see from certain popular race fuels; is deosits left behind in the combustion chamber that are not only corrosive, but are causing poor sealing of valves. Testing will also show if any of this nasty "sand like" meterial is between surfaces, hurting that critical component of a competetive engine.

For help in eliminating this issue; we recommend purging your engine with pump gas after your race and spraying a storage oil product or 2 stroke oil mix into the intakes while running. This is very important if the engine is going to sit a while.

So get yourself a differential gauge like the ones available from Snap-on, Mac or Motion-pro. Follow the manufacurer instructions and take care not to use too much pressure as this can hurt rod bearings.

Are All Valve Jobs Created Equal?

Mon, 01 Mar 2010 19:09:00 +0000

I often hear of people who mix up valve lash (clearance) inspection/adjustment with a valve job. The latter actually refers to refurbishment of valve seats & faces and measurement & inspection of all related valve train components; valve clearance checks are simply routine maintenance.

The job of a valve seat is more complex than most people realize, but I will explain the basics to help you understand the importance this part of your engine plays in the performance of the whole package.

The seat provides the required seal to ensure optimum compression. It also acts a a heat sink to cool the valve. The various angles and widths of the valve and seat are critical with respect to maximum flow potential. So it should now be obvious that a deficiency in this area can cause all kinds of problems.

The most important component of a good valve job is concentricity. This will both ensure optimum seal and promote a longer life span for both surfaces.

In order to obtain the most concentric seats with perfect repeatability, an engine builder must utilize modern methods and equipment such as SERDI. The old stones and singular cutters such as Neway just cannot produce the desired results of the live pilot, blade type machines. Also note that "lapping" is what a dog does in its water bowl, and has no place in a performance engine, as it just hides a poor valve job! (It is also the best way to destroy a titanium valve found in most modern engines).

Consider that with a SERDI valve job, all valve heights can be equallized, which not only standardizes spring seat pressures, but alows the builder to verify combustion chambers are the same volume (an often overlooked source of power in multi-cylinder engines).

In closing, be sure to find out what method your engine builder utilizes, as now you can make an informed decision.

Am I Race Ready?

Thu, 25 Feb 2010 18:46:00 +0000

So you went to a manufacturer, dealer or swap meet and bought yourself a racecar and had your expert buddy help you set-up, scale etc. Then your cool new numbers and graphics showed up. You purchased gear sets, extra wheels and all that stuff that you tell the wife/girlfriend cost about 15% of actual price! Now you just go to the local wrecker, pick up a used motorcycle engine, have someone leak test or compression test it, install it with fresh oil & filter, fire it up and go enjoy an economical racing career! Right?

WRONG!!! Please understand that the purpose of my rant is to save the new racer some of his/her hard- earned money.

First, lets think about the origin of that sweet new engine. It came from a sportbike (which means it was not used by a nice old lady to fetch groceries on Sunday!) and, believe it or not, most of the engines from crashed bikes etc, have likely had a rough life before landing in the boneyard. For this reason, it is in your best interest to have a professional do a complete inspection of your purchase before you install it in that sweet new ride. Ask anyone how much a used superbike engine with a big ventilation hole created by the connecting rod is now worth! This situation can happen due to many factors including inadequate oil changes, wrong type/grade of oil (which we will discuss further in a separate article), oil starvation (caused by too many wheelies!), acidic pitting of bearings due to storage with old oil, etc. Many other components require verification and / or repair, but I wanted to point out the need for a complete tear down including the bottom end.