ESE's works engine tuner

[41juergen]

hey guys on the yami twin theres a small hose from the head to top of rad. im guessing this is a self air bleeder like the bleeder screw found on most other heads. what im not sure of is if its only purpose is just for the first time the system is filled and after that its useless. ?

And during cold start, when the thermostat is still closed, it might reduce a bit the water pressure when slightly reving up the engine...?

[jbiplane]

Thank you for the Patent's. It tells me a lot about where things are at currently.

Some of the ideas are close to mine. Reading what they claim and based on my experience I doubt any of them have a working example.

Stihl and Husqvarna both sucseed in fuel injection on disk saw STIHL TS 500i
This year they will start STIHL MS 500i
What ideas and algorithms used unclear. Both companies have few EFI related patents...
May be good idea reverse engineer one of those EFI ?

[F5 Dave]

So, . . What sort of throttle response is required on a saw?

[Grumph]

So, . . What sort of throttle response is required on a saw?

Suburbanite....Response should be at least equal to the best bikes, preferably better. With no flat spots or hesitancy.
Instant return to a steady idle is a prerequisite too.

[wobbly]

The VF2 was not designed for the NF4 , it was a CR125 part that also fitted the TM125MX.
But it made better power than the NF4 reeds and way better than the later VF3.
In the race bike the outers hit the case .
The petals are too thin , and the 1st mode resonance is too low for running to over 12,000 all day.
I got Tassinari to make special petals with biased carbon weave , that solved the issue running a TM125MX to 13,000 all day.

[jasonu]

So, . . What sort of throttle response is required on a saw?

Instant!!!

[TZ350]

Stihl and Husqvarna both sucseed in fuel injection on disk saw STIHL TS 500i This year they will start STIHL MS 500i What ideas and algorithms used unclear. Both companies have few EFI related patents... May be good idea reverse engineer one of those EFI ?

I would love to know more about Stihl performance, peak torque rpm, bmep etc; and anything about Stil's EFI and how they arrange the injector(s).

My own experience has lead me to believe that you can successfully fuel inject any two stroke using the common Alpha-N topology. Unless the motor is heavily reliant on symbiotic pipe resonance for its power, like a Honda RS125 or Aprilia road racer. Because when you throttle off, the pipe resonance collapses and so does the airflow. Current 2S EFI systems don't cope well with dramatic changes in pipe suction.

Currently there is no proven method I know of that can detect this change of airflow in a high performance single cylinder racing two stroke. So you get very poor EFI throttle response with racing single cylinder two strokes that are producing more than 10 bar BMEP. Anything less than 10 bar BMEP should be relativly easy to fuel inject and get good throttle response. The lower the BMEP the easier it will be to fuel inject successfully. And because it's a time thing, over 9-10,000 rpm you will also need staged injection.

I expect exhaust pipe induced air flow does not change much in industrial two strokes, making it much easier to map the industrial 2S EFI for good throttle response.

[husaberg]

So, . . What sort of throttle response is required on a saw?

Hand in Your Kiwi Bloke id immediately. Anyone lucky enough to have ever seen Ron Hartill use one to carve stuff you would know what a Chainsaw can do.

In the Bloke code its written Most blokes would rather lend out their wife than their Chainsaw.

They also need to work on any angle or way up, thats why they have a pumpercarb. Like a KT100S

[F5 Dave]

Well funnily enough I'm in turangi cleaning out dads Bach of 35 years. I've left behind a realatively new McCulloch chainsaw . I'd just rather use a lithium saw. Too scared of chainsaw.
As far as the Kiwi man card goes, tell them to turn up with 2 slick shod 50cc racers and see of they can beat me around any track despite my doting years
Good luck with that.

[husaberg]

Well funnily enough I'm in turangi cleaning out dads Bach of 35 years. I've left behind a realatively new McCulloch chainsaw . I'd just rather use a lithium saw. Too scared of chainsaw.
As far as the Kiwi man card goes, tell them to turn up with 2 slick shod 50cc racers and see of they can beat me around any track despite my doting years
Good luck with that.

Can you beat Av?

[jbiplane]

So, . . What sort of throttle response is required on a saw?

Stihl report chain acceleration from 0 to 100km/h for amazing 0.25 seconds

[speedpro]

I don't know, but I suspect there will be a centrifugal clutch in there somewhere. So - engine revs to ??,000rpm and then clutch grabs. The engine doesn't pick up that fast, just the clutch.

[F5 Dave]

And further not what speed of acceleration but how controlled?

[F5 Dave]

Can you beat Av?

I might have had a drink last night and been spouting bile.

If we can change the question to have I beaten Av before? Yes. When she was a kid. On occasion I've also beaten Jay and Sketchy and a whole raft of other teenagers (who grew up and would now wipe the floor with an old man).

[TZ350]

Stihl report chain acceleration from 0 to 100km/h for amazing 0.25 seconds

I don't know, but I suspect there will be a centrifugal clutch in there somewhere. So - engine revs to ??,000rpm and then clutch grabs. The engine doesn't pick up that fast, just the clutch.

Agreed, it is all about the clutch. Idle speed is 2,500 rpm so the flywheel inertia at whatever speed the clutch takes up would accelerate the chain quite quickly. Still amazing though, and frightening.