is STIHL the only one doing 4-mix and how does that make more power than 2-stroke?

[r7000]

- does any other OPE manufacturer produce a blower/trimmer/saw that is a 4mix like Stihl does?
- Stihl claims 4mix has more power, if so how come we don't see 4mix chain saws?
- I see online that no 4mix saws because they don't turn enough rpm, which I disagree with because if the power was there just make the sprocket larger to turn the chain at the necessary speed.
- and how do you get cleaner emissions, when you're still burning 2-stroke oil?

 

[Nutball]

Cleaner because of 4 stroke tech. More power than a regular 4 stroke because it is crankcase charged like a 2 stroke, so it's kind of a supercharged 4. I don't know how the power compares, but it still probably doesn't match a 2 stroke.

 

[mrxlh]

4 mix have more torque. New 2 stroke oil isn’t boat oil of the 60’s nor are the ratios.

 

[Sloughfoot]

Does Stihl put a 4 mix motor on anything but a few trimmers?

 

[SOS Ridgerider]

They're not 4 Mix, but for what it's worth; Makita has/had real 4 stroke blowers and trimmers/power heads. No mix oil required.
I have one of the multi tool power heads myself, and it does just fine. May be picking up a 4 stroke blower soon as well.
They make absolutely no sense, but that's kind of the fun of them.

 

[CAMike]

I have a Honda UMC435 with most of the Honda atttachments. It’s lower HP but it does have good torque. I change the crankcase oil once a year and it runs like great, now 7 years old. Once in a while I add a little 2 stroke oil to the fuel and it still doesn’t smoke. https://www.acmetools.com/honda-versattach-multi-tool-umc435laat/786102005630.html

 

[Sloughfoot]

I have a Honda UMC435 with most of the Honda atttachments. It’s lower HP but it does have good torque. I change the crankcase oil once a year and it runs like great, now 7 years old. Once in a while I add a little 2 stroke oil to the fuel and it still doesn’t smoke. https://www.acmetools.com/honda-versattach-multi-tool-umc435laat/786102005630.html

I've got a Honda 4 stroke brush cutter that has a lifetime of use on it in 5 years. Never thought of putting some mix in the fuel. What's it do?

 

[Nutball]

Make it run leaner.

 

[hacskaroly]

Does Stihl put a 4 mix motor on anything but a few trimmers?

Their higher power trimmers and blowers, here are a few benefits off of Stihl's website:

• Familiar fuel mixture ratio (50:1)
• Operates in all positions
• Cleaner - reduced emissions
• More power - high torque
• Good acceleration - quick starts
• Low fuel consumption
• Favourable power-to-weight ratio
• Compact construction - attractive design
• Fewer vibrations
• Low noise level

I have a FS 91R, works really good, though I wish I had gotten the version with the bike handles on it. Though if you are used to just 2 stroke engines and one of these 4-Mixes decides it doesn't want to start (won't fire at all), you need to check and make sure neither of the rods slipped off a valve.

 

[el33t]

- does any other OPE manufacturer produce a blower/trimmer/saw that is a 4mix like Stihl does?

Since 4-Mix is a trademarked name of Stihl, so only they sell such engines. But as for similar technology, Shindaiwa introduced their idea of a four-stroke engine lubricated by oil in the gas/oil mixture at a similar time as Stihl 4-Mix (2001-2002).
They used such engines in many types of equipment, except, of course, chainsaws.


They first referred to such engines as C4, then as H4 (Hybrid 4). After the merger with Kioritz, such equipment rather disappeared from the market. What's left is their partially working website dedicated to this technology.

Hybrid 4 Engine Technology for Trimmers, Blowers, Brushcutters, Edgers and Multi-Tools | Hybrid4Engine.com

Hybrid 4 Engine technology is the absolute best choice available today, and it's brought to you by the same legendary Shindaiwa name that introduced the renowned T27 Trimmer, the revolutionary Speed-Feed head, and the Power Broom™. Hybrid 4 is the latest innovation representing the next...

www.hybrid4engine.com

- Stihl claims 4mix has more power, if so how come we don't see 4mix chain saws?

IMHO a 4-stroke engine has no chance to match a 2-stroke in power/weight ratio. And this is especially important for chainsaws, the use of which is more "dynamic" than other equipment, such as, for example, strimmers, which can use a harness.
This hasn't stopped at least one Chinese OEM from launching four-stroke chainsaws, which are sold in Europe under a number of local brands.
They use traditional lubrication and, in their case, there is no need to mix oil and gasoline.

- I see online that no 4mix saws because they don't turn enough rpm, which I disagree with because if the power was there just make the sprocket larger to turn the chain at the necessary speed.

You can't arbitrarily increase the diameter of the drive sprocket (increase the number of teeth/pins), because this is limited by the existing guide bars. The chain has to get on the bar in the right way (hence the special shape of the bar tail), and too large a sprocket diameter could cause problems with that.

 

[Squareground3691]

Their higher power trimmers and blowers, here are a few benefits off of Stihl's website:

• Familiar fuel mixture ratio (50:1)
• Operates in all positions
• Cleaner - reduced emissions
• More power - high torque
• Good acceleration - quick starts
• Low fuel consumption
• Favourable power-to-weight ratio
• Compact construction - attractive design
• Fewer vibrations
• Low noise level

I have a FS 91R, works really good, though I wish I had gotten the version with the bike handles on it. Though if you are used to just 2 stroke engines and one of these 4-Mixes decides it doesn't want to start (won't fire at all), you need to check and make sure neither of the rods slipped off a valve.

I have a 27 year old FS80 , probably the best trimmer they ever made , runs great,

 

[lehman live edge slab]

The Stihl 4-mix and shindiawa hybrid were co developed that’s why they came out about same time and Stihl/shindiawa both have shared design patents. They came up with this design to make a lighter 4 stroke that could run at any angle. With no oil in case they could design a smaller lighter engine that ran on common mix for your other Stihl equipment. The 4-mix is on lots of the larger pro trimmers and blowers. They reduce emissions because you’re trapping the mix for a more complete burn since it has valves to keep it from pushing raw mix out exhaust just like stratto two cycles use an fresh air charge to help the raw mix stay in the cylinder.

 

[lehman live edge slab]

I have a 27 year old FS80 , probably the best trimmer they ever made , runs great,

If it’s the old fs-80 like the old fs-66 and fs-90
I have check to see where it’s made. If it says Japan like my fs-66 and my fs-90 with the upside down cylinder they were made by shindiawa for Stihl. Stihl years ago made brush saw attachments for certain chainsaws ect but when they got into the small trimmer market they had shindiawa build them for quite some time before making their own designs.

 

[lehman live edge slab]

If it looks like this it’s a Japanese made one by shindiawa

 

[David Boyd]

I doubt anyone wants to come out with chainsaws or more products using "4mix" type technology. When 4mixes were released Stihl claimed they HAD to develop the technology because it was going to be impossible to produce 2 strokes that met emission standards. The 4 mix machines are substantially heavier, more complicated and require more maintenance than comparable 2 strokes and Stihl lost significant market share when they were introduced.
Not a path most companies want to follow.

 

[Squareground3691]

If it looks like this it’s a Japanese made one by shindiawa

I’ll have to do a closer inspection,

 

[lehman live edge slab]

In fact some of these old trimmers had baby slide carbs that were a night mare

 

[Squareground3691]

In fact some of these old trimmers had baby slide carbs that were a night mare

I just replaced the carb 2 years ago, and it was a OEM Stihl carb i used. I’ll try to post pics later,

 

[el33t]

I just replaced the carb 2 years ago, and it was a OEM Stihl carb i used. I’ll try to post pics later,

If your trimmer is 27 years old, it is rather a new version (Series 4137), which was available since the second half of the 1990s.

 

[stretch5881]

I know there are thousands of them out there and the owners like them. I have had only 1 in my garage and I would not want to own one.
Let's take a simple 2 stroke and triple the amount of moving parts. My thoughts are negative on it.
The one in my garage dropped a valve. Piston is shot, broken rod, cylinder is screwed and a bad crank bearing. The blower looks brand new but is 4 years old. Not much time on it.
I would rather have a smaller 2 stroke and a big tarp.