Throttle Response

[davidwyby]

What mods help or hurt it? How do we get more snappies?

Thanks

 

[ferris]

Muff mods
Carb work

 

[jacob j.]

Possibly help: Lighter reciprocating assembly, advanced ignition timing (depending on the design of the motor and what other mods have been done),
lighter flywheel, etc.

 

[Ketchup]

Large case volume or short case pressure stage (intake close to trans open) can make sluggish transfers. That usually equates to bad throttle response.

 

[davidwyby]

How about a muffler being too open?

 

[slackinoff]

Hey David, I like a fast revving saw too.

I think it has more to do with torque and bar/chain friction. Most saws sound WAY snappier without a bar and chain.....so it's got to be the friction and inertia of getting that chain going. Torque would help that I think.

Also, putting a larger carb on my 61, I did not loose any snap at all. In fact it helped it a bit. I thought smaller carbs are better for throttle response but eh....depends.

 

[Stevetheboatguy]

Slick 50 for bar oil


Steven

 

[Dolkitafreak]

Most saws I’ve come across are snappier with wide open mufflers, especially straight out the front.

 

[Ketchup]

How about a muffler being too open?

Not that I have experienced. Some really open mufflers on stratos may cause the saw to lean out while returning to idle.

 

[Funky sawman]

Very good subject. I'm a known throttle blipper, heck I'm even part of the local blipping club! It sucks when a saw can't keep up with a fast trigger finger. The 500i I ran today was very responsive to blips so I naturally fell in love. Now if only Stihl would make a 241 size saw with fuel injection and instant throttle response.
I try to limb trees while walking down them and it helps to have a quick saw so the saw and you work together more smoothly. I don't know, I get flamed all the time for blipping throttle out working, but it's just my style, if you don't like it, pound on horse crap!

 

[Matt Ellerbee]

Very good subject. I'm a known throttle blipper, heck I'm even part of the local blipping club! It sucks when a saw can't keep up with a fast trigger finger. The 500i I ran today was very responsive to blips so I naturally fell in love. Now if only Stihl would make a 241 size saw with fuel injection and instant throttle response.
I try to limb trees while walking down them and it helps to have a quick saw so the saw and you work together more smoothly. I don't know, I get flamed all the time for blipping throttle out working, but it's just my style, if you don't like it, pound on horse crap!

It’s like picking up a set of tongs. They won’t work right if you don’t give them a few test clomps.

 

[merc_man]

It’s like picking up a set of tongs. They won’t work right if you don’t give them a few test clomps.

Fack that made me laugh. I always grab the tongs and clomp them a few times. Drives my wife nuts.

Sent from my SM-G950W using Tapatalk

 

[davidwyby]

Gotta blip the throttle twice before you go for the clutch

 

[drf256]

I’ve found that the correct ignition advance and the correct size intake tract and port make the difference. Ports need to as small as possible and still provide good performance. Nice and tight.

Some saw models are just snappier than others by design. I hate a lazy saw.

 

[Loony661]

I think a lot of times, we get caught up in the “bigger is better“ theory when in reality this hurts more than it helps. In the 4 cycle engine world, intake size is very carefully calculated on high performance engines. What I’m getting at is volumetric efficiency. A lot of times, a ported intake tract will be made too large, therefor reducing the velocity of the incoming intake charge. By the time the valve shuts, not much of the charge has entered the cylinder. On the contrary, a smaller intake tract (On the same displacement cylinder) will have a higher velocity, therefor increasing its volumetric efficiency, and packing the cylinder with more charge before the valve shuts. On high end race engines, volumetric efficiencies are usually over 100%...

I apply the same theory to a piston port 2 cycle like a chainsaw engine: the piston being the “valve”, keeping the intake small enough to maintain high velocity should be considered. The more you can pack into the crankcase, the better.

 

[Loony661]

Obviously there is a trade off, and too small of an intake tract will not allow enough charge through. Trial and error will be the best teachers here.. some may respond better to being ported, other may need to have some epoxy added for higher velocity..

 

[Maintenance Chief]

Id have to go with @drf256 on the ignition system part ,I know a chip really adds some snap to the old piston port saws . I'm not knowledgeable enough about transfers to comment on those.
I do wonder about a lightened piston though with the advent of the new stihl magnesium piston.

 

[Carhartt]

I wish every saw snapped like a 200T. I have some saws that drag ass in throttle and a few that impress. Some have muffler mods.

 

[drf256]

I wish every saw snapped like a 200T. I have some saws that drag ass in throttle and a few that impress. Some have muffler mods.

Accelerator pumps help in that respect.

 

[Mastermind]

I’ve found that the correct ignition advance and the correct size intake tract and port make the difference. Ports need to as small as possible and still provide good performance. Nice and tight.

Some saw models are just snappier than others by design. I hate a lazy saw.

Yep.....yep yep.