Do Spyders have an enriching circuit for Starting?

[Bill]

Does the 2014 Spyder Rt limited have an enriching circuit for starting ? :dontknow:

[BLUEKNIGHT911]

Does the 2014 Spyder Rt limited have an enriching circuit for starting ? :dontknow:

Taking a guess on this, but I think all modern gas engines have this. ... I know on my 14 RT, initially it runs at 1200 RPM's then after about one minute it settles down to 900 ..... JMHO .... Mike :thumbup:

[IdahoMtnSpyder]

Does the 2014 Spyder Rt limited have an enriching circuit for starting ? :dontknow:

No. Enriching circuit is specific to carburetors. Spyders, from day 1, have been electronic fuel injected. The ECM performs a similar function by regulating the throttle opening and fuel injection during engine operation, including starting.

[redrazor]

Taking a guess on this, but I think all modern gas engines have this. ... I know on my 14 RT, initially it runs at 1200 RPM's then after about one minute it settles down to 900 ..... JMHO .... Mike :thumbup:

:agree: My 2014 is exactly like Mike's. 1,200 at startup and 900 in 1 minute or less; just like most new cars. :thumbup:

[trikermutha]

The engine will begin to operate in open loop when first started, and switch to closed loop operation when the oxygen sensor reaches its operating temperature.
At high engine loads, the engine reverts again to the open loop.

[sledge]

Taking a guess on this, but I think all modern gas engines have this. ... I know on my 14 RT, initially it runs at 1200 RPM's then after about one minute it settles down to 900 ..... JMHO .... Mike :thumbup:

is this the same for a 2011 ???

[IdahoMtnSpyder]

:agree: My 2014 is exactly like Mike's. 1,200 at startup and 900 in 1 minute or less; just like most new cars. :thumbup:

But that doesn't mean it has an enriching circuit.

[pegasus1300]

is this the same for a 2011 ???
Yes only our VTwins idle a little higher. 1500-1600 at first then settle down to 1300-1400.

[BLUEKNIGHT911]

But that doesn't mean it has an enriching circuit.

IMHO ..... that's just semantics.... call it whatever makes you happy ......Mike :thumbup:

[IdahoMtnSpyder]

I wasn’t aware of “a fuel enrichment circuit” until this thread started. That sent me on a Google search. In the interest of adding to our collective knowledge about all things Spyder let me share what I have learned.

The enrichment circuit concept and design was developed as a means of improving on the use of a choke butterfly valve to add extra fuel to the air stream passing through a carburetor to make cold engine starting easier. It actually replaced the use of the butterfly valve by including in the carburetor a separate fuel passage to draw extra fuel from the bowl and dump it into the air stream during starting. See a description here:


https://www.youtube.com/watch?v=hDsJH1Y9W_U

As we know, Electronic Fuel Injection has supplanted the use of carburetors. Some early EFI systems still needed some help to enrich the air/fuel ratio during starting. There were designs that included a second fuel injector for that purpose. Those also were referred to as fuel enrichment circuits. As the control of air flow and fuel injection processes were refined in later ECM and EFI designs, the need for a secondary fuel supply into the air stream during starting was rendered moot.

There is a fuel enrichment action that takes place during starting, but it is accomplished by the ECM by longer pulses of fuel injection. There is no fuel enrichment circuit, per se, in our Rotax engines. It’s all controlled by the computer code in the ECM. There is no discussion of fuel enrichment in the 2013 or 2014 Spyder maintenance manuals.

Fuel enrichment is the process. Fuel enrichment circuit is a physical configuration.

[BertRemington]

Yes there is -- the enriching circuit is in the ECM firmware.

The 1330cc engine is a nice piece of engineering. Buy the electronic service manual and read more about it. As well as the rest of the machine. You'll appreciate your Spyder more.

[IdahoMtnSpyder]

Yes there is -- the enriching circuit is in the ECM firmware.
Are you saying even though the enriching process is software (firmware is simply software that doesn't disappear when power is removed) it is still referred to as an enriching circuit by the engine industry? I see circuit as meaning a physical feature, not a software path. Everything I've found in a Google search has focused on circuit being applied to a physical configuration meaning a separate fuel path beginning with carburetors. I don't recall ever seeing the word circuit applied to a software path such as a DO loop.

If the word circuit has been expanded by the industry to include the portion of the algorithm that enriches the fuel at startup, then I'll agree the Rotax has an enrichment circuit. In that case I don't know why the OP even asked the question because every ECM for many years has included a fuel enriching circuit in its algorithm. But to my way of thinking the fuel enrichment process should be referred to as a fuel enrichment mode since it is just one of many specific groups of parameters that control engine operation.

[BLUEKNIGHT911]

Are you saying even though the enriching process is software (firmware is simply software that doesn't disappear when power is removed) it is still referred to as an enriching circuit by the engine industry? I see circuit as meaning a physical feature, not a software path. Everything I've found in a Google search has focused on circuit being applied to a physical configuration meaning a separate fuel path beginning with carburetors. I don't recall ever seeing the word circuit applied to a software path such as a DO loop.

If the word circuit has been expanded by the industry to include the portion of the algorithm that enriches the fuel at startup, then I'll agree the Rotax has an enrichment circuit. In that case I don't know why the OP even asked the question because every ECM for many years has included a fuel enriching circuit in its algorithm. But to my way of thinking the fuel enrichment process should be referred to as a fuel enrichment mode since it is just one of many specific groups of parameters that control engine operation.

ie. " semantics ".... :clap::roflblack::roflblack:...... JMHO ..... Mike :thumbup:

[Peter Aawen]

It truly is semantics Idaho - the narrow definition of 'a circuit' that you are referring to is a mechanical (think early choke's) &/or mech/electrical circuit, or in earlier EFI engines, it may even be a largely electrical circuit. ;) . The wider definition of 'a circuit' that everyone else is referring to is a software/firmware computer circuit.... they achieve the same thing by (really only slightly) different methods - regardless of which circuit type your particular engine might use, the fuel/air mix is modified at start-up to help get the engine running, then the circuit allows it to revert to 'normal operation' parameters once the engine's running & starting to warm up sufficiently. Same task, slightly different way of achieving said task; same end result! :thumbup:

And it's still a valid question from the OP, cos not all early EFI engine's had a mechanical/electrical circuit to control the air/fuel mix at start up, some few still relied upon a mechanical device to achieve the same end (like a carby engine's choke) only as EFI's & the associatec control technology matured, it became possible to do that sorta stuff mechanically via (largely binary) sensors & electrical controls; then when integrated computers started being used instead of simple binary logic control devices, computers & their on-board tables took over that function - effectively still binary, but with waaayyy more options & if/then decisions involved. But in the final wash, it's still a circuit driving the fuel enrichment at start-up :thumbup:

[BertRemington]

My apologies Idaho. I was trying to answer the question in its original framework.

The ECM has two AFR maps, one for open loop operation and one for closed loop operation (HEGO feedback). Startup would use the open loop map plus various additional algorithms to address specific actions (eg, the throttle plate is operated through its full range of motion when ignition is first turned on then the throttle control is ignored* until the starting sequence is completed and idle speed is achieved; compensate for low voltage while starter motor is engaged by adjusting fuel injection duration; etc). Its quite fascinating if you like control systems. I've read Charles Probst's Ford Fuel Injection book several times.

* except for Drown Mode

As to the question whether software has circuits, well there is Basis Path Testing https://en.wikipedia.org/wiki/Basis_path_testing It's likely Bosch validated its mission-critical ECM firmware using this test method, among others.

PS I just found this Circuit (computer science) https://en.wikipedia.org/wiki/Circuit_(computer_science)

[BertRemington]

Mike -- two primary reasons for fast idle after startup. First, to rapidly heat the catalytic convertor to reduce emissions. Second, even the 1330's short intake manifold will collect atomized fuel when cold so extra fuel and higher air velocity are used to improve combustion.

[cravenfun]

Just to add to this one should let the motor run a bit after a cold start so fuel mixtures can lean out and plugs heat up to ''clean'' off.
At least let it run long enough so idle speed drops down to it's normal rpm to get it out of cold start open loop mode.
With Rotax 1200 3 cyl. snowmobile engines lots of guys have fouled plugs doing a quick start/stops with cold motors. Same hassle of major disassembly to access plugs on sleds just like on Spyders. Same engine programming across the board with Rotax injected 4 stroke motors.
Fuel injection on these are no different that your other gasoline vehicles IE cars and trucks.

[FrogmanDave]

Way off topic. The Honda ST 1300 engine actually uses wax to set start up rpm's. As the wax melts, as the engine warms up, the rpm's are allowed to drop. I always thought this to be a very crude system given the modern design of this engine/efi. It does work and is effective but weird none-the-less. This thread is way beyond what I understand but is interesting.

[crtsteve55]

Glad to hear my 2013 RT/S SE5 is idling right. It is about the 1100-1200 rpm after warm up.