What EXACTLY happens to your TRIMMER with GUARD OFF - Science Experiment!

String Trimmer Guard ON or OFF? We ran the trimmer at different line lengths, without the guard, to see what it exactly does to your trimmer. With a heat gun, a measuring tape, and a tachometer, we aim to bust some myths!

You can find tons of content on this debate. However, at Main Street Mower we did not just want to give you our thoughts. We want to give you the numbers behind the science of it. So tune into this crazy experiment video, where STU and Chip attempt to BURN DOWN a TRIMMER engine.

The Truth About Removing Your String Trimmer Guard

What's up, everyone? Chip here from Main Street Mower, alongside my brother Stu, and today, we're diving into a hot topic regarding string trimmers without guards. Many of our customers have queried about the longevity of their trimmers when they tinker with the guard and line length. Spoiler alert: This could drastically shorten your trimmer's lifespan.

Why Removing the Guard is a Problem

Typically, a string trimmer can last up to five years if handled correctly. However, pulling off the guard to extend the line might reduce its life to just a year. We decided to put this theory to the test using various tools including a heat gun and a tachometer to get down to the numbers.

What Happens During the Tests?

We embarked on a series of tests to analyze how extending the string length impacts the motor's performance. Initially, we demonstrated what happens to your trimmer with the standard line length and then gradually increased it, recording the temperature and performance at each stage. Here’s what went down:

Baseline Test with OEM Line Length

In our controlled environment, we started with the trimmer set to the manufacturer's prescribed line length. We let it run and monitored the temperature and RPMs.

Increasing the Line Length

After removing the guard, we incrementally increased the line length from the standard 5 and 3/4 inches up to 12 and 3/4 inches to push the limits.

Surprising Insights from the Tests

Here are some key observations:

  • Motor Stress: As the line length increases, the RPMs drop significantly, decreasing the engine's efficiency and overheating occurs.
  • Temperature Peaks: We noticed a substantial rise in temperature as more line was added. The motor temperature seemed to plateau after a certain point, likely due to the unburned fuel providing a cooling effect.
  • Potential for Damage: Extending the string, especially beyond recommended lengths, critically impacts the mechanics. The increased line length puts undue stress on the motor and can lead to quicker wear and tear.

Practical Consequences

Using a trimmer without a guard and with a longer line might seem like a small tweak, but it leads to significant repercussions:

  • Decreased Efficiency: The trimmer struggles to maintain its efficiency, leading to more frequent maintenance.
  • Increased Operational Costs: The trimmer's lifespan is considerably reduced, leading to higher replacement or repair costs.
  • Safety Risks: Operating a trimmer without a guard increases the risk of injuries from flying debris or the trimmer itself malfunctioning.

Conclusion: Is It Worth the Risk?

In conclusion, while removing the guard on your string trimmer might seem like a good idea for reaching those tough spots or trimming larger areas quickly, the long-term damage and costs are not worth it. The added strain on your motor and the decrease in life expectancy are significant. Stick to the recommended settings for a durable and efficient tool. Always remember, safety first, efficiency second. Hope this helps you understand why we, and many experts, strongly advise against tampering with your trimmer’s guard. Stay safe and keep trimming smart!

If you've got experiences or additional insights on using string trimmers with or without guards, drop us a line in the comments! Thanks for reading, and happy trimming!

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