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How To Fix Motorcycle Engine Pre-Detonation

Written by Charleen

 

How To Fix Motorcycle Engine Knock

Your bike can automatically detune its engine, but there’s an easy fix.

_by Eddie Hilgendorfen |May 10, 2023

Many modern motorcycles are designed to compensate for low-octane gasoline in an attempt to prevent motorcycle engine knocking. Unfortunately, the technology involved may also cause reduced performance, rough idle or lack of throttle response, making for a less than stellar ride experience. Fortunately, we can help you understand the root cause of this problem, and offer an inexpensive, quick and easy solution.

What is engine knocking?

Engine knock  or pre-detonation is caused by an improper detonation within the engine, which happens when fuel ignites outside of a timed ignition from the spark plug. In the race to improve fuel economy, modern high-performance engines have increased compression ratios, which also inherently increases the chance of pre-ignition detonation.

Octane measures gasoline performance against pre-ignition, detonation and the resulting engine knocking or pinging. The three most common octane ratings are:

  • Anti-Knock Index (AKI)
    The rating typically displayed on North American gas station pumps as the average of the fuel’s RON and MON octane ratings (R+M)/2.
  • Research Octane Number (RON)
    This rating is determined by testing fuel using a variable compression ratio under controlled conditions and is the most common industry rating worldwide. When comparing octane ratings, RON is typically higher than the AKI number, so an 87-octane AKI fuel at a typical gas station typically has a RON of 91-92. AMSOIL uses RON when conducting product validation and performance testing.
  • Motor Octane Number (MON)
    MON differs from RON testing by using a preheated fuel mixture, variable ignition timing and a higher engine speed to increase ignition stresses on the fuel. Though the tests are unrelated, MON results are typically 8 to 12 octane lower than RON.

Causes for loss of power and efficiency

Low-octane gasoline is more susceptible to uncontrolled and early ignition in the combustion chamber, so the higher the octane, the more compression the fuel can withstand before igniting. Pre-ignition robs the engine of power, can cause a noticeable knocking or pinging sound, and if left unchecked, can even cause catastrophic piston or cylinder damage.

This is why I decelerate (turning off the cruise control) when driving up or climbing steep hills and I also sometimes turn off the air conditioning. Also doing this you can see A decent increase in your fuel efficiency

High stress combined with lightweight design caused this dirt bike piston to fail. Dude was in first place so missed out on the cash prize.

Reduced performance.

Many modern motorcycle engines are equipped with a knock sensor. Pre-Detonation causes this sensor to adjust timing to compensating for low-octane gasoline. Unfortunately, adjusting the timing usually results in a noticeable decrease in performance, rough idling and lack of throttle response. When timing changes are done correctly, most riders shouldn’t even be aware that the performance has been reduced, but it’s easy to resolve this performance problem.

Boosting octane To Reduce Knock

The risk of engine knock can be reduced by:

  • retarding ignition timing
  • enriching the air-fuel ratio
  • reducing cylinder pressure or engine load
  • reducing the throttle or boost especially as you climb a hill
  • increasing the octane rating of the fuel
  • Engine work – lower compression

Therefore, the performance degradation caused by reduced engine timing can most easily be eliminated by increasing the fuel’s octane number. AMSOIL Motorcycle Octane Boost increases octane up to three numbers. On a bike that can be significant! This helps to eliminate motorcycle engine knocking and maximize power, performance and fuel efficiency. We get a LOT of feedback on this. Check out the product reviews.

 

 

 

 

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Why Do I Need To Change My Oil?

Written by Charleen

What Happens to oil Making Me Needing to Change It?

Dan McClelland|

Regardless of its quality, every motor oil eventually loses its potency and must be changed to ensure peak engine protection. Let’s take a look at what happens to motor oil over time and why you periodically need to change oil.

Losing the base

Base oils are the backbone of the finished lubricant that ends up in your engine. Over time, they lose effectiveness due to the following factors:

Oxidation

The interaction between oxygen molecules and motor oil molecules naturally leads to chemical breakdown.

Just as oxygen causes a cut apple to brown or exposed metal to rust, it breaks down base oils and reduces motor oil’s effectiveness.

Oxidation can lead to increased oil viscosity, which negatively affects energy efficiency. It also causes the formation of harmful deposits and sludge.

High heat

Today’s engines run hotter than ever before, with temperatures up to 235°F (113ºC), and even higher if towing or hauling.

The rate of oxidation for oil doubles for every 18°F (10°C) increase in temperature.

Moisture

Your vehicle is subjected to temperature swings, even when it is parked in the garage.

Those temperature swings cause condensation to form inside your engine, leading to water contamination.

Leaving a vehicle parked for extended periods or taking short trips that don’t allow the engine to fully warm up allow water to remain in the oil rather than evaporating and exiting through the tailpipe. Water can lead to formation of sludge…yet another reason why you must change oil.

Viscosity is a motor oil’s most important property. The lower the viscosity, the faster the oils flows, like water. Thicker oils flow more slowly, like honey.

Viscosity loss

A lubricant’s viscosity is its most important property.

Viscosity has a direct bearing on wear protection, and your engine is designed to operate best using a motor oil of a specific viscosity (e.g. 5W-30).

The intense pressure the oil bears as it’s squeezed between moving parts, like the piston ring/cylinder wall interface, can tear apart, or shear, its molecular structure, leading to viscosity loss.

Suddenly, the 5W-30 motor oil your engine was designed to use is now essentially a 5W-20 oil, and wear protection may be compromised. When this happens, it’s time to change your oil.

Shop AMSOIL Synthetic Motor Oil

Fuel dilution

Fuel can wash past the piston rings and contaminate the motor oil, causing it to lose viscosity.

Frequent short trips that don’t allow the oil to reach normal operating temperature can be especially problematic because the fuel won’t volatilize and exit through the PCV system.

Excessive fuel dilution leads to sludge and varnish, requiring you to change oil more frequently.

Additives: Additives are added to base oils to reduce destructive processes and enhance beneficial properties.

For example, antioxidant additives help slow the rate of oxidation. Detergency additives help prevent deposits and sludge while cleaning pre-existing deposits. Formulators add anti-wear additives to some lubricants to form a sacrificial barrier on metal components and help prevent wear.

Since they’re sacrificial in nature, additive depletion is one of the primary reasons motor oil loses its effectiveness and must be changed. 

While AMSOIL synthetic motor oil gives you the convenience of fitting oil changes into your schedule, it remains vital to install fresh oil at the appropriate time.

Shop AMSOIL XL 12,000 mile Synthetic Motor Oil
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How Engine Wear & Deposits Kill Horsepower

Written by Charleen
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Common Engine Wear & Deposits Will Kill Horsepower

John Baker|

Most people equate engine wear and deposits with a sudden, catastrophic engine failure that leaves you stranded alongside the road. In reality, wear and deposits are more likely to erode engine power and efficiency over time. Here’s how it works and what you can do about it.

Engine compression = power

For your engine to produce maximum power, the combustion chamber must seal completely during the compression and combustion strokes. Wear and deposits can prevent the valves or piston rings from sealing, allowing pressurized gases to escape the combustion chamber and take potential engine power with them.

To illustrate, imagine using a hydraulic floor jack. Pumping the handle will raise the vehicle as long as the release valve is tightly seated and doesn’t leak. A poorly sealed release valve, however, allows pressure to escape, causing the vehicle to sink to the ground no matter how much you pump the jack handle.

The same principle applies inside your engine. If some of the pressure created during the compression and combustion strokes is lost due to valves and piston rings that don’t seal completely, the engine will create less power.

engine wear identified

Wear & deposits reduce compression

Over time, deposits or valve wear can prevent the valves from closing completely, interfering with a good seal. Wear can also interfere with proper valve operation, disrupting optimum fuel/air flow.

If the piston rings do not seal tightly against the cylinder wall, pressurized combustion gases can escape past the rings and enter the crankcase, taking potential power with it.

Worn or stuck piston rings produce the same effect. The rings are designed to move freely in their grooves and press tightly against the cylinder wall. They should form a seal that prevents fuel/air from escaping. Ring wear can interfere with formation of a tight seal. Likewise, deposit buildup can cause the rings to stick in their grooves, also preventing a good seal. As a result, some fuel/air escapes the combustion chamber during compression, reducing power. On the combustion stroke, pressurized gases can blow by the rings and travel down the cylinder wall and into the oil sump, taking potential power with them. This is what’s meant when someone says an engine has lost compression.

(Check out our 5 Ways to Boost Horsepower for Under $500)

AMSOIL Signature Series helps prevent the problem

AMSOIL Signature Series Synthetic Motor Oil provides…

  • 75 percent more engine protection against horsepower loss and wear*
  • 90% better protection against sludge **

Its outstanding performance helps prevent deposits and wear that rob engines of horsepower, helping preserve that like-new feeling you crave when driving.

FIND AMSOIL PRODUCTS FOR MY VEHICLE

*Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.

**Based on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required by the API SN specification.

Maintenance, ,

Oil Analysis Kits – They’re Easy

Written by Charleen

How to Perform Oil Analysis

We keep these kits right here in the Omaha store. Ask for the one with postage or with out for a slight savings. When doing several vehicles use the one w/o postage to send all together.

John Baker|

Used oil analysis is one of the most potent tools in your vehicle-maintenance arsenal. It effectively provides a glimpse inside your engine to gauge lubricant and component condition without so much as removing a bolt or bloodying a knuckle. And it’s simple and inexpensive. Here’s how to perform oil analysis.

What is oil analysis?

First, let’s define our terms.

Oil analysis is the process of chemically analyzing a lubricant sample (typically used motor oil) to determine lubricant and engine or component condition.

You take a sample of the lubricant and ship it to a qualified laboratory. Technicians subject the lubricant to a range of tests to determine the concentration of wear metals, fuel dilution, the lubricant’s total base number (TBN), oxidation and other information. The lab sends you a report that shows lubricant condition and includes a brief explanation and recommendations for future service.

The benefits of oil analysis

Determining the condition of the oil inside your engine offers a number of benefits, all of which save you time, money and hassle in the future.

Maximize oil drain intervals

Monitoring the condition of the oil allows you to optimize drain intervals so you can capitalize on the fluid’s full service life. Performing fewer oil changes minimizes maintenance costs and, for businesses that depend on vehicle availability, maximizes uptime. It also vastly reduces the amount of waste oil you have to truck to the recycling facility, helping the environment.

Extend equipment life

Monitoring system cleanliness and filtration efficiency can help you keep your vehicles and equipment longer and significantly reduce replacement costs.

Prevent major problems

Oil analysis identifies dirt, wear particles, fuel dilution, coolant and other contaminants that can cause catastrophic failure or significantly shorten equipment life. Arming yourself with this information allows you to proactively fix problems before they spiral out of control.

Maximize asset reliability

For businesses that maintain vehicle fleets, testing and analysis ensure that equipment is up, running and making money instead of laid up in the shop.

Increased resale value

Performing oil analysis provides valuable sampling history documentation that can justify higher equipment resale values.

How to perform oil analysis

To demonstrate how easy it is to perform oil analysis, I obtained an oil analysis kit from Oil Analyzers INC. and identified the perfect subject from my family fleet – my trusty 1998 Toyota Corolla. I thumped down exactly $2,995 for the car more than three years ago, and it’s been bulletproof ever since. In fact, it was used in this demonstration of how to test engine compression. Check it out to see how it performed.

Here’s what you’ll need to perform oil analysis on your vehicle

1) Warm up the engine

Warm oil flows more easily through the sampling pump. In addition, circulating the oil prior to drawing a sample ensures consistency. Just run the vehicle for a couple minutes; there’s no need to bring it up to operating temperature.

2) Draw the oil sample

Using a vacuum pump is the easiest and cleanest way to accomplish this. It allows access to the oil sump through the dipstick tube. Thread a clean sample bottle to the pump. Attach a length of clean hose to the top of the pump and tighten the lock ring.

PRO TIP: To know how much sampling hose to use, measure the dipstick and add a foot.

Insert the opposite end of the tube into the dipstick tube. It helps to cut it at a 45-degree angle to avoid snagging on bends or restrictions.

Once it bottoms out in the oil sump, retract the tube about an inch so it’s not pulling contaminants off the bottom of the oil pan. Pump the plunger until the bottle is 3/4 full.

Sometimes it’s impossible to draw a lubricant sample through the dipstick tube. In these cases, you can pull the sample straight from the reservoir, although it’s messier. If this is the case, allow the lubricant to drain for a couple seconds before catching a sample in the bottle so contaminants that have settled around the drain plug are flushed out. Quickly reinstall the drain plug and top-off the reservoir.

3) Ship the oil sample

Most oil analysis kits come with the appropriate labels and directions for shipping it to a lab. Follow the instructions, then hang tight until the results arrive.

4) Read the results

I can’t speak for all oil analysis labs, but Oil Analyzers INC. typically returns results in about two days after receiving the sample. I received a PDF in my inbox the day after the lab had received the oil sample.

Shop Oil Analysis Kits

The lab sends a report that includes application information, elemental analysis and recommendations. The amount of information varies depending on the kit you use.

Let’s take a look at the report for my ’98 Corolla.

oil analysis sheet

It’s important to note that I put 10,915 miles on the oil over the course of 11 months. First, notice the severity status level in the upper right. It provides a quick reference to determine the status of the sample.

  • Severity 0 (Normal) = Oil is suitable for continued use.
  • Severity 1 (Normal) = Oil is suitable for continued use. Observe for trends in future tests.
  • Severity 2 (Abnormal) = Oil is suitable for continued use. Resample at half the normal interval.
  • Severity 3 (Abnormal) = Replace oil filter and top-off system with fresh oil. Resample at half the normal interval or change oil.
  • Severity 4 (Critical) = Change oil and filter if not done when sample was taken.

My sample fell into the Severity 2 category. Why?

Notice the Multi-Source Metals and Additive Metals highlighted in yellow.

The information in the Comments section explains why: “Flagged additive levels are lower than expected for the identified lubricant. This may have been topped off with a different lubricant, the fluid may be misidentified, or a different lubricant or formulation may have been in use prior to a recent change.”

Nailed it.

I’m guilty of having topped-off the engine with a different AMSOIL product than the Signature Series 0W-30 Synthetic Motor Oil initially used for the oil change 11 months earlier. This report shows why you shouldn’t mix lubricants, if possible. Sure, it won’t do lasting harm to the engine, but mixing lubricants disrupts the oil’s chemistry and can shorten its service life and reduce performance.

Learn from my negligence, friends – don’t mix engine oils.

Reading an oil analysis report

You can also see fuel dilution is moderately high while TBN is moderately low. As Allen Bender, Oil Analyzers INC. Manager told me, the TBN is no cause for concern and there is “considerable time” before the oil would have to be changed.

All in all, this is a good report for a 21-year-old engine with more than 150,000 miles, most of it using who-knows-what motor oil.

Wear metals are low, meaning the oil is doing a great job protecting the bearings and other components from wear. Contaminants are also low, meaning the air filter is capturing silicon and other debris before it reaches the engine. The report shows no glycol contamination, which means the engine coolant is where it’s supposed to be – in the cooling system – and not in the oil via a leaking head gasket or other issue. And oil viscosity and oxidation are both good, showing that the oil is holding up fine, even after 11 months.

The one area that provides a little concern is 3-percent fuel dilution. As noted, this is a moderate level and shouldn’t cause alarm, but it is something to watch.

This is a perfect example of the power of oil analysis. It allows me to monitor the fuel-dilution level and potentially take action if it increases to a problematic level. Knowing the engine suffers moderate fuel dilution also reinforces the importance of using a high-quality synthetic oil (and not mixing oils!) to ensure maximum protection.

Give oil analysis a try. It’s relatively cheap for the information it provides and it empowers you to take better care of your vehicles while maximizing their return on your investment.

Shop Oil Analysis Kits

We have all the main oil analysis kits here in the Sioux Falls store. 47073 98th st. Just behind Marlins found at Exit 73 on I-29.

605-274-2580

 

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Is Starting Fluid Bad for Gas Engines?

Written by Charleen
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Is Starting Fluid Bad for Gas Engines?

 

John Baker|

The simple answer: In small doses and used properly, it can be effective in hard-starting gasoline engines. But it can be bad for two-stroke or diesel engines. The real question to ask is, “Why does my engine need starting fluid in the first place?” Find out the answer, then fix the real problem.

The detailed answer: Ask five gearheads or mechanics their opinion of starting fluid, and you might get five different answers.

Some occasionally use it to help revive an engine that’s been pulled from storage. Others use it to help coax a stubborn engine to life on a frigid morning.

Yet others won’t touch starting fluid. One mechanic I talked to blamed starting fluid for ruining the bearings in a two-stroke outboard motor. Its owner, the story goes, liberally sprayed starting fluid into the intake when the engine wouldn’t start. And sprayed. And sprayed.

Starting fluid typically contains ether, which is an effective solvent. In this case, the starting fluid likely washed the inside of the engine clean of oil, allowing metal components to contact and eventually seize.

Diesel engines, too, can suffer the effects of starting fluid. Their high compression can cause the fluid to ignite too early, effectively causing pre-ignition, which invites all kinds of problems, like catastrophic piston or rod damage. Plus, it has no lubricating properties, so it can hasten piston wear.

With minimal work, you can find all sorts of cautionary tales on the Internet of people blowing up engines after using too much starting fluid.

Starting Fluid Does Sometimes Work

Given the disdain many harbor toward starting fluid, why would anyone use it?

Because it can be effective in gasoline engines – especially carbureted engines – when used as directed.

For gasoline to combust, it must first be vaporized. The fuel injectors in your car or truck do a great job of completing this task.

In carbureted engines, fuel is vaporized as it’s forced through the tiny openings or nozzles in the carburetor. But carburetors don’t vaporize fuel as effectively as fuel injectors. Plus, gasoline doesn’t vaporize as readily when it’s cold. Anyone who’s started a carbureted car on a frigid morning knows this all too well. Plus, an engine requires more gas in the fuel/air mixture at startup, making a cold engine doubly difficult to start and keep running.

Starting fluid, on the other hand, does readily ignite in the cold, helping to start the engine and generate heat to more easily vaporize the fuel.

But a little goes a long way. Many of the problems with starting fluid can be attributed to operator error rather than the fluid itself.

In short, if you have to use starting fluid, use it sparingly. If a couple short bursts of spray into the intake don’t elicit a cough or two from the engine, emptying the can isn’t going to work, either.

No amount of starting fluid is going to revive an engine with a dirty carburetor. Identify the real problem and get it fixed.

Ask yourself this…

Instead, ask yourself why the engine needs starting fluid in the first place. There’s likely a bigger problem that needs fixing.

I was presented with this exact scenario last fall when my snowblower refused to start. So I reached for a can of starting fluid and gave the intake a shot. She sputtered a few times and quit. I repeated the process a few times, with the same result.

I should have used Quickshot when it was sitting right there when I last filled the tank. Would have solved this issue all together.

Eventually, I took apart and cleaned the carb. She roared to life on the first pull after that. In my case, emptying the entire can of starting fluid into the engine wouldn’t have done a thing, aside from washing the oil from the cylinder and causing wear. At the very least, it helped me diagnose what the problem was not: lack of spark or bad compression.

Bottom line: Starting fluid can help start a stubborn engine, but follow the directions and use it sparingly. If a little bit doesn’t work, a lot likely won’t, either. If your engine is consistently hard to start, find out why and get the real problem fixed.

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