Forum

[Tim NZ]

Keeping things simple:


The BPR6EIX will be too 'cold' for the motor while running in. As such it will show a 'rich' (cold actually) indication. A '7' or an '8' may have been better for low speed running-in?


IF the plug does start to misfire, (?was it?) you have nothing to worry about giving the Bike a 'Handful' for a 5-10 second blast in a lower gear to clean off any loose carbon matter on the plugs insulation.


Presuming sensible running-in with the occasional tweek on the throttle in low load situations your piston and rings will be pretty much run in by now and will stand being given the occasional 3/4 - full 10 - 15 second runs, again; in a low load situation.




As for the Idle speed adjustment; technically it is not an Idle Adjustment, but rather it is an air-bypass bleed; it offset the effects of the 'Idle' fuel injection settings...

[Tim NZ]

WARNING! WARNING!


Extreme case of BRAIN FADE!!

[Thack]

Tim NZ writes: "As for the Idle speed adjustment; technically it is not an Idle Adjustment, but rather it is an air-bypass bleed; it offset the effects of the 'Idle' fuel injection settings... IF the actual 'Throttle stop' screw on the side of the body has be adjusted, (?) Oops! Then you will need to get the whole FI system recalibrated..."



No, you won't! That whole paragraph is nonsense!!

[zonggong]

Thanks all for your considered and worthwhile advice/comments. It is all extremely helpful. I'm satisfied with the integrity of the air filter and induction side having checked these and tightened a number of the bolts that did not seem to be nipped up enough. I have a BPR6ES and will fit it later today and then I will ride it, giving it a bit more stick now that it should be 'run-in', and see how it goes. I'll let you know. Thanks again for all your help. I appreciate it.

[Tim NZ]

Cut and paste from latest edition of the WS service manual:




An idle air bypass screw is provided on the throttle body. It is the large brass coloured screw that is
accessed from the top of the throttle body. The clamps on the throttle body may be loosened and the
throttle body rotated outwards from the top to access the screw without removing the fuel tank and
to adjust the idle speed with the bike running. Turn the screw CLOCKWISE (in) to DECREASE the
idle speed. Turn the screw ANTICLOCKWISE (out) to increase the idle speed. Remember that this
is an AIR BYPASS screw – not a throttle stop screw. Turning the screw about ¼ turn will result in an
approximate 200 RPM change in the idle speed. DO NOT adjust the throttle stop screw on the side
of the throttle body unless you are using the factory software to recalibrate the base throttle opening.

[jefrs]

Plugs and their numbers - Bosch increase as the get hotter, NGK decrease as they get hotter. We done that but - the Bosch-India plugs ain't Bosch, they're a bit weird and their heat numbers are a bit weird too. The EFI-500 uses a 7 and the CGT EFI-535 uses an 8 in Bosch-India.

Neither NGK nor Bosch (euro) list a direct equivalent for these Bosch-India WR7DCC4 and WQR8DC. Imo both of which are rather low build quality.

The WR7DCC4 is usually given as NGK BPR6ES or BP6ES but then so is the hotter CGT WQR8DC plug. Working backwards, NGK list the (hotter) BPR5ES as equivalent to a Bosch (euro) 8 and the NGK 6 as the euro-Bosch 7 or 8 . This may not make much sense but it seems the NGK 6 and 5 are only about a half-step apart in heat.

The heat of a plug has much to do with mow much or little ceramic is wrapped around the electrode, this dictates how fast it can conduct heat away and how well it self-cleans. Obviously the engine heats the plug but it may not get it hot enough to self clean, or it may get it too hot.

If a plug is getting filthy it is not self cleaning, the motor is not getting it hot enough, try using a plug with a higher heat number. I am not suggesting you use anything too extreme but within the 500/535 normal range.

[jefrs]

Thack - interesting info. Did you assess this yourself ?

Information gleaned from elsewhere, typically on Dynojet sites* suggests the excessive pulsing down the exhaust, most especially on a single (and Harleys) at idle confuses the squit out of narrow O2 sensor and thus the ECU switches over to open loop. Which is why most if not all dyno developed maps Do Not Map the 0% and 2% throttle columns, especially around the idle rpm, although we may use them further up the revs to cure reversion popping.



Cars often have a wide band O2 sensor and multiple cylinders hence closed loop is possible at idle. Both of our cars do this but then they are both turbos and one is a diesel with a stage 1 tweak. Many cars have variable valve timing, I would not call them tamer as some are very aggressive but the flow down the exhaust will be smoother than a single.



With my wide band Bosch sensor in play i.e. open loop, I can see it controlling the AFR at idle, and it makes a pretty good stab at it. I actually had to insert an AFR Target number otherwise it was doing nothing and the O2 sensor reading was all over the place as it was then running on the stock ECU alone which has the PCV resistor dongle in place of the narrow-band Lambda. (ah ha!)

>br>
I have just been for a run on the bike and the AFR Target mapping seems practically perfect. I have not yet hooked up the laptop to see the Trim table but I did enter a value of 13.5 at 0% throttle and 1000rpm. I hav enot done the screen shot and will also check the throttle calibration volts.

If I have calculated correctly the Trim should return a more-or-less zero trim there this time i.e. the stock ECU is set to provide 12.9 to 1 AFR at idle (quite rich, stoichiometric being 14.7). Gleaned from those other sites* - without the wide O2 sensor the injector would be providing a fixed amount equivalent to this on average but still using the MAP to gauge the correct feed (*trouble is there is a lot of duff information on the web). Still a work in progress and will refine data as it progresses. I have not altered the Hitchcocks dyno-mapped region at all. The bike ran very smoothly with almost instant throttle response and only one little reversion pop, more of a crackle.

[jefrs]

Typo - correction read "12.9 at 0% throttle" (not 13.5, I read the wrong box/field)

[Rattlebattle]

To summarise, if I have understood correctly, it seems to me that when running in and/or using a standard spec bike for short runs or just cruising at 50-55mph the best thing to cure sooty plugs is to use a hotter one eg BPR5ES. Those who work the engine harder and longer would seem to be better off with the standard colder plug. If one intends to tune the engine and/or fit less restrictive air filters and exhausts then either PCV (or EJK) would appear to be necessary or, if preferred, the cheaper carb conversion. I get the impression that the PCV alone may not suffice if perfection is sought throughout the Rev range. I intend fitting the carb conversion tomorrow. I'll report back in due course.

[Thack]

jefrsr writes: "With my wide band Bosch sensor in play i.e. open loop, I can see it controlling the AFR at idle, and it makes a pretty good stab at it."



Ah! You are getting your terminology confused.



When the O2 sensor is "in play" you are operating CLOSED loop, NOT open loop.



Closed loop means the ECU is monitoring the effects of its actions. Its "actions" are controlling the FI pulse duration, the "effects" are the O2 reading. That is what closed loop means: the ECU uses the output values (from the O2 sensor) to control the input values (the FI pulse duration).

Open loop means there is NO feedback loop back to the ECU. In other words, it uses an internal map to set the FI pulse duration, and hopes the mixture is what it should be.



So we've been talking at cross purposes due to a confusion over terminology. Remember: closed loop means the ECU uses a feedback loop from the O2 sensor to control the mixture. Open loop means there is no feedback loop - ie no O2 sensor in play.