Stihl FS-90 string trimmer mini-rant

[N80]

I have a fair amount of Stihl equipment and generally it has been worth the higher price.

I have two FS-90 string trimmers. They are solid shaft. They seem very powerful. Stihl says they are their professional/commercial line. I've had them for at least 5 years, maybe more.

They have been reliable.

But they have two flaws in my opinion and I thought I'd share them for potential buyers. I think the latest comparable model is the FS-91 which looks identical.

First, one of the reasons I bought these is that they accept different heads. I have a hedge trimmer, sidewalk edger and a brush saw adapter in addition to the trimmer head. Well, the shaft that engages these different units is roughly square shaped and it is a pain in the fanny to get it engaged with the various heads. It seems like an oversight or just bad design but it is very fruatrating at times.

Second, the way the engine is oriented all of its weight is upward. Maybe this is true with all gas powered trimmers. But, it makes the unit awkward. That weight up high like that makes the trimmer want to twist in your hands. When using for long periods this increases fatigue and makes it more tiring to us.

Otherwise I have found these units to be very good.

I posted a separate post asking for advice on better string.

 

[kozal01]

I have the KM130 version which is just the larger engine and split shaft version and I dont have much issue changing out attachments. Sometimes I have to fidle with it but it usually slides right in. As for the weight balance, yeah it could be better but as a 4 stroke engine it is a bit top heavy compared to a 2 stroke. I use mine mainly for the pole saw, brush cutter and edger attachments, got too heavy as a daily trimmer so I have a lightweight 2 stroke trimmer for that now.

 

[oldballs]

I use the harness to operate my FS-90, handle bar style brush cutter...using the string most of the time. Being 91 YO and 137 pounds 5'4" tall, I do find it tiring after several hours........ Bought it in May of 2015. Changing blades etc has not been a problem for me... just saying...Occasonal maintenance keeps it easy to start and run....got lots of hours on it.

Cheers,
Mike

 

[Gem99ultra]

I use the harness to operate my FS-90, handle bar style brush cutter...using the string most of the time. Being 91 YO and 137 pounds 5'4" tall, I do find it tiring after several hours........ Bought it in May of 2015. Changing blades etc has not been a problem for me... just saying...Occasonal maintenance keeps it easy to start and run....got lots of hours on it.

Cheers,
Mike

Being 91 YO, 137# & 5'4" - consider yourself very lucky to being even able to pick up a FS-90.
Congrats!!!

 

[Mud2Money]

There is a company that makes after market handles. They reduce fatigue a lot and bending over. I’ll have to ask my lawn care friend what the brand was. I tried his trimmers with them and what a world of difference. You can get your trimmer balanced pretty well.

 

[N80]

I have the harnesses for both of my trimmers. I'm a little too tall for them and they cause me to stoop over.

 

[RjCorazza]

There is a company that makes after market handles. They reduce fatigue a lot and bending over. I’ll have to ask my lawn care friend what the brand was. I tried his trimmers with them and what a world of difference. You can get your trimmer balanced pretty well.

I use the Darwin Grip on both of my trimmers. They adjust up and down the handle, as well as distance from the shaft.

 

[D'oh]

Bicycle Handle and a strap, It's not the Motor Weight as much as the motor Torque pulling the motor away from your body (Right Handed). Try grabbing the D Handle at about 10:00 rather than 12:00 to offset some of it's torque.

 

[dodge man]

When I bought my Stihl trimmer I was set on a straight shaft. I found a curved shaft one that just fit me better. It turned out it had a longer shaft meant for taller people. I’m not that tall either, a little over 6 feet tall. Is yours a little short for you?

 

[Runner]

I have an old (like 18 years) Stihl FS series trimmer. It has a black ribbed grip on the shaft, behind the plastic hoop and ahead of the trigger handle. The grip is hard plastic and appears to be intentionally made so the shaft can rotate. I just looked at a photo of a new Stihl trimmer with the same handle.

For all these years, I have never been able to understand the purpose of this design. The location is not a convenient place to hold it with the left hand while trimming because it's too far back. However, it is in the exact place where I want to hold the handle while just carrying the unit from one place to another.

Problem is, if I try to carry it this way, the loose handle lets the unit rotate upside down because it is top heavy.

Does anyone understand the purpose of this handle design and do you actually use it in the manner intended by Stihl?