average rpm

pete g

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hi all, can someone tell me what the lo and hi rpm of most string trimmers? what rpm should they idle at? thanks.
 
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metz12

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hi all, can someone tell me what the lo and hi rpm of most string trimmers? what rpm should they idle at? thanks.

7000rpms is a pretty decent amount. it wont fray the ends of the line and if you hit your jeans or your boot it wont slice through it!!:laughing:
 

Ric

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hi all, can someone tell me what the lo and hi rpm of most string trimmers? what rpm should they idle at? thanks.

Most of your string trimmers like Echo and such are going to be around 2700 to 3000 rpm lo Idle speed and your High speed is going to be 10,000 rpm. Stihl Lo rpm is 2800 high is 10,500 for the 4 mix units. If you are using a cutting tool the max is 7500 rpm. It should tell you in the manual for the machine if you have it. As a rule of thumb you can set the low idle until the engine runs smoothly and the trimmer head doesn't rotate, if the head spins the idle is to high.
 
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As a rule of thumb you can set the low idle until the engine runs smoothly and the trimmer head doesn't rotate, if the head spins the idle is to high.

I have an Echo GT-2100 that was purchased around 25 years ago. When I use it I noticed that when it is at "full-throttle", it sounds a lot more powerful and more "revved up" than my new SRM-225 at full power. Also, when it is idling the head does spin. So from what you said that means that the idle rpm is too high, and maybe that causes the "full-throttle" rpm to be too high also? Correct?
 
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Ric

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I have an Echo GT-2100 that was purchased around 25 years ago. When I use it I noticed that when it is at "full-throttle", it sounds a lot more powerful and more "revved up" than my new SRM-225 at full power. Also, when it is idling the head does spin. So from what you said that means that the idle rpm is too high, and maybe that causes the "full-throttle" rpm to be too high also? Correct?

If the Trimmer head spins then the idle is set to high, the clutch should not engage at idle. You have a idle adjustment, high and low speed adjustment screws on the 2100. If you adjust the idle to the point where the head just starts to spin then back it off so the clutch doesn't engage or spin the head, you should be running some where around 3000 rpm and that should not have any effect on the top end speed of the unit.
 
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If the Trimmer head spins then the idle is set to high, the clutch should not engage at idle. You have a idle adjustment, high and low speed adjustment screws on the 2100. If you adjust the idle to the point where the head just starts to spin then back it off so the clutch doesn't engage or spin the head, you should be running some where around 3000 rpm and that should not have any effect on the top end speed of the unit.

OK thanks for the info! :thumbsup:
 
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