Full throttle Stihl startup

[Wolfy]

Any owners of newer Stihls know how to start them at idle speed. Especially in the brush, Im not a fan of the OEM full throttle setup.

 

[Bird]

My Stihl FS55RC string trimmer is also set up to start cold at full throttle and, like you, that just doesn't seem best to me, so I do go back to idle as quickly as possible when it starts. After it's warmed up, it can be shut down, and restarted at idle just fine. But I haven't used a Stihl chainsaw in more than 10 years, so I don't know about them.

 

[Wolfy]

Bird, I have a Stihl FS90R trimmer, it runs like you said. I don't get why they can start at idle yet the saws don't. Every time they start, its automatic full throttle.

 

[Fixemall]

2 strokes depend on the lube in their fuel, WOT start ensures proper lubrication from the first fire

 

[Wolfy]

Fixemall, that makes sense. Maybe I should live with it.

 

[Bird]

2 strokes depend on the lube in their fuel, WOT start ensures proper lubrication from the first fire

Maybe that's best for those engines, and I hope you're right. But my Mantis tiller uses the same 2-cycle fuel mix as the string trimmer and it has to be started at idle and allowed to warm up 2 to 3 whole minutes before you can speed the engine up. Try to open the throttle too soon and you just kill the engine.

 

[Fixemall]

Maybe that's best for those engines, and I hope you're right. But my Mantis tiller uses the same 2-cycle fuel mix as the string trimmer and it has to be started at idle and allowed to warm up 2 to 3 whole minutes before you can speed the engine up. Try to open the throttle too soon and you just kill the engine.

It is set way too lean, give both the H and L a little fuel and it will last longer.

 

[Bird]

It is set way too lean, give both the H and L a little fuel and it will last longer.

I won't dispute what you say, but I can tell you that the manual also says to allow it to warm up 2 to 3 minutes before using, and I've personally adjusted the carb to specs in the manual. And if you allow it to warm up, as the manual says, then it runs great at full throttle.

 

[turnkey4099]

On the saws, set the chain break and it will be at idle speed when it starts. Blip throttle takes it off full throttle, realeas chain break and you are in business.

Harry K

 

[Fixemall]

I won't dispute what you say, but I can tell you that the manual also says to allow it to warm up 2 to 3 minutes before using, and I've personally adjusted the carb to specs in the manual. And if you allow it to warm up, as the manual says, then it runs great at full throttle.

You are mostly warming it up to protect the gearbox components, as far as tuning a two stroke there is only one proper way...run at WOT and turn the H screw open till it 4 strokes and then turn it back slowly till it stops 4 stroking, as far as the L, it should be set so a non warmed engine won't stumble when the throttle is blipped. I know others use tachs etc but I have done it by ear for over 20 years.

 

[Bird]

You are mostly warming it up to protect the gearbox components, as far as tuning a two stroke there is only one proper way...run at WOT and turn the H screw open till it 4 strokes and then turn it back slowly till it stops 4 stroking, as far as the L, it should be set so a non warmed engine won't stumble when the throttle is blipped. I know others use tachs etc but I have done it by ear for over 20 years.

OK, i'll bite . . what are you talking about when you say "4 strokes"?

And you've only done it for 20 years; must be a youngster. I've been doing it for over 50 years.:laughing: And yep, this little Mantis is different from anything I've had in the past.

 

[turnkey4099]

You are mostly warming it up to protect the gearbox components, as far as tuning a two stroke there is only one proper way...run at WOT and turn the H screw open till it 4 strokes and then turn it back slowly till it stops 4 stroking, as far as the L, it should be set so a non warmed engine won't stumble when the throttle is blipped. I know others use tachs etc but I have done it by ear for over 20 years.

Can the new saws with EPA mandated tuning/limiter caps even be richened to the point of 4 stroking?

Harry K

 

[Bird]

OK, i'll bite . . what are you talking about when you say "4 strokes"?

And you've only done it for 20 years; must be a youngster. I've been doing it for over 50 years.:laughing: And yep, this little Mantis is different from anything I've had in the past.

At least I found on the Internet other places that talk about 4 stroking; never heard it called that before. Just one more thing I've learned on TBN.

 

[beppington]

I wear ear plugs every time I use my Stihl stuff (pole pruner, blower, trimmer); Just can't stand the noise any more. Ear also plugs help me not mind the full throttle starts as much.

 

[PapaPerk]

Can the new saws with EPA mandated tuning/limiter caps even be richened to the point of 4 stroking?

Harry K

You can after you break the plastic limiters off! :laughing: I despise those things!

 

[PapaPerk]

You are mostly warming it up to protect the gearbox components, as far as tuning a two stroke there is only one proper way...run at WOT and turn the H screw open till it 4 strokes and then turn it back slowly till it stops 4 stroking, as far as the L, it should be set so a non warmed engine won't stumble when the throttle is blipped. I know others use tachs etc but I have done it by ear for over 20 years.

The gear box is not turning at idle so you aren't warming anything up except the clutch. :laughing:

 

[Fixemall]

Can the new saws with EPA mandated tuning/limiter caps even be richened to the point of 4 stroking?

Harry K

No, so sometimes "adjustments" are needed...
4 stroking is just a reference to the point of richness where it breaks up enough to loose power strokes every second pass, thus "four strokes" is more of a loose term...however, I did hear if you adjust on em enough, valves and a cam may actually appear:laughing:

 

[Fixemall]

OK, i'll bite . . what are you talking about when you say "4 strokes"?

And you've only done it for 20 years; must be a youngster. I've been doing it for over 50 years.:laughing: And yep, this little Mantis is different from anything I've had in the past.

Wish I was younger, worked in a salvage yard and as a mechanic in my younger years, then went into the corporate world for a long time, hated it! Finally got out when my health and marriage failed, best cure was to move onto acreage, back to turning wrenches and raise some animals...I still have a lot to learn though, we stop living when we stop learning...

 

[PoorPlowboy]

The gear box is not turning at idle so you aren't warming anything up except the clutch. :laughing:

How does physics, specifically thermal energy transfer, work?

 

[yomax4]

My new Stihl Weed Eater and Pole saw are both 2 cycle 4 stroke engines that both will only start with the throttle wide open. I am unsure of this new 4 stroke 2 cycle engine but time will tell. They use mix'd gas but only fire on the 4th stroke. My older Stihl Saws do start at full throttle too. There is the choke and it pops once, Then the next setting makes it run wide open until you click the trigger. Then it idles while it warms up. I don't think my saws would start at idle.