BS6/Euro5 questions

G

ginger bread man

Active Member
Looks like I can get my hands on a nice euro5 Himalayan in the UK, wonder what peoples views are on them?
Do they run even leaner and is that a problem? and can you do anything to tune the efi to go with a cam and downpipe?

cheers
 
Its a PITA. If you can avoid it do. The Euro4 is way easier to tune which is obvious considering the Euro5 (aka BS6) ECU is glued to the TB which takes access to various sensors out of the equation for piggyback ECUs of any kind and the PT V4 which is the only one on the market right now does not even access the O2 sensor, so open loop only. For close loop you need to buy the FuelX Pro, then cram the entire shebang under your seat. And although I do have both my carby Hima is way faster than my BS6 Hima with all the goodies on board.
 
thanks, are the euro5's running very lean? are they getting damaged from heat or are they quite reliable?
Other thing I wondered about is fitting HC's carb kit for the euro4 to a euro5, is there any reason that wouldn't work?
 
The carb kit is actually a very good idea where its legal (only in UK I think). Carb bikes are way easier to tune and maintain, However this will only work on the Euro4 models. Again, for the same reason: the ECU in the carb kit still manages the ignition and in the Euro5 the ECU is glued to the TB which will be replaced by a carb. The Euro5 is of course running very lean - that is the whole point of this insane "climate change" bullshit going on.
To a degree you can get it to run with a BB kit (I did) but it will never be as effective as in a carby bike.
 
Fully with you on the climate change crap.
I don't understand how the TB and ECU etc are working on the euro5, but on the euro4 carb kit the ECU is still used and the carb has a TPS on it to give a reading. Could the euro5 TB not still be inline with a carb and the butterfly removed, the throttle cable would have to work the carb and TB and just don't connnect fuel to the TB, only the carb?
If the euro5 TB and all it's ECU etc is so clever that it will know, somehow, that it is being fooled what will it do? Would it just give a CEL or would it shut down? I guess the only option then is to buy a full wiring harness and bits from a euro4 and fit that along with a carb but then it is getting to be a lot of work.
 
I was just thinking about this again, because a carb fit would be so good. HC's carb kit is good and fitting it in place of the euro5 TB should be very straight forward, the kit also get rid of the fuel pump. The euro5 TB with ECU could be 'shelved' and a euro4 ECU 'found', to connect the euro4 ECU a fly lead would need to be made and run, from the big connector at the old TB and the TPS on the new carb, to the new euro4 ECU under the seat.
The carb kit has a cost, a 2nd hand euro4 ECU has a cost, both probably worth it, the only hard part to do is make the right connections with the fly lead! Does that sound like a realistic solution? Forgeting cost for a moment, thinking of purely what would make the best machine.:coffee:
 
Anything is possible but not everything is worth doing. Yeah. if you invested a lot of work figuring out how the E5 ECU works and where it gets its signals etc. etc. it maybe doable. But I would not even think of doing it. It is way easier (and likely also cheaper) to get a Euro4 Hima if you want to go the carby route. I for one am lucky enough to get cheap BS3 original stock carbys here which when converted to 500cc are real rockets. I just did a stunt today with one of the new 450s and due to traffic I could only race it to ca. 80kmh but hey, I was leading ... and here anything over 80 is dangerous and 100 is really top of the line if you want to stay alive long term.
In terms of "best" there are improvements in the E5 over the E4 but few. The better rack can be adopted, so can the side stand. If you are a sucker for optics you could arrange the entire front part to look like E5 (but expensive). But why? The "better" front brake has turned out to be a fairy tale and with better brake pads that is easily fixed in any case. I have modified my bikes to the max, just for fun - I have a floating 300mm Brembo disk and caliper (from the 535 conti) on one of my Himas (800 euros!) and taken off the entire shebang from the front side to make it more like a scram (before the scram came out) - also my tank holds 18 litres and many other improvements - but it is a carby bike in its heart.
one with 33 HP though (approx 36 or so BHP but with a lot more torque in the lower rpm than the 450).
 

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Quick question again - do you know if getting rid of the cat downpipe and fitting a cam would make a euro5 run leaner? No mods to intake.
 
I don't know. Purely speculative the cam will allow more mixture to enter the chamber, this mixture has more air but not more fuel (the ecu does not know about the cam). Now the exhaust flows easier which supports this further. But if I had a E5 (and I do) I would get a FuelX Pro (and I have) anyway to spice the mixture when cruising. During acceleration the ECU will inject more fuel anyway (but maybe not enough for the configuration).
Keep an eye on the spark plug. if it gets whitish or very light brown the mix is too lean. If the electrode is burnt then definitely.
 
Sweet!
FuelX will be on the cards for sure. Think I heard tec talking about their cam in E5 saying not to do any airbox mods and it is ok.
Got me wondering if the injectors can be tweeked, it is a plug in part of the efi chain so maybe one that is 5% greater fuel injection per firing could be used to tune for richer? Not something I know anything about really.
 
Afaik mainly the amount of time of the injection and not the size of the injector determines the fuel flow.
 
Having a quick read it sounds like fuel pressure effects the output from the injectors, ie higher pressure more flow. Wonder if the fuel pressure regulator at the top of the fuel pump can be modified? Might have a talk to our local rally car injector tuners and see what they say, they do system mods.
It might be that some of the very lean problem bikes just have poor pressure regulators fitted.
 
here you have it from the horses mouth:

Fuel flow in an EFI system is primarily regulated by time, specifically the duration of injector opening. However, there are other factors that play a role:
1. Injector Open Time: This is the key factor controlling fuel flow. The ECU (Electronic Control Unit) determines the desired amount of fuel based on various engine parameters (RPM, air intake, etc.). It then sends a signal to the injector, telling it how long to open and release fuel. The longer the injector stays open, the more fuel flows through.
2. Injector Size: While not the main control method, the size of the injector nozzle also influences flow. Larger nozzles allow more fuel to pass through in a given time, while smaller ones deliver less. However, injectors are typically pre-calibrated and chosen to match the engine's needs, and their size isn't directly adjusted to regulate fuel flow.
3. Fuel Pressure: Although not the primary control method, fuel pressure can indirectly affect flow. In some systems, a pressure regulator maintains a constant pressure in the fuel rail, ensuring consistent delivery. However, in common rail systems, the pressure can vary dynamically based on engine demands. This can slightly impact flow but is not the main control method.
Additional Factors:
  • Temperature sensors: Engine and air temperature affect air density, influencing the required fuel. The ECU adjusts injector open time based on these readings.
  • Oxygen sensors: These sensors monitor exhaust oxygen levels, indicating the air-fuel ratio. The ECU adjusts injector open time to maintain the optimal ratio for efficient combustion and emissions control.
In summary, the primary control for fuel flow in an EFI system is the injector open time, determined by the ECU based on various engine parameters and feedback from sensors. While injector size and fuel pressure play supporting roles, they are not directly manipulated to regulate flow.
Click to expand...
 
The Hima is NOT a common rail system, the fuel pump consistently gives the same pressure when on.
 
Ah ok. So pretty tied up system then. So at the moment FuelX can help a bit with standard bike and posibly a cam, bigger mods would maybe want a Powertronic? And an ecu remap would be the simplest solution of all!
 
ginger bread man said:
Ah ok. So pretty tied up system then. So at the moment FuelX can help a bit with standard bike and posibly a cam, bigger mods would maybe want a Powertronic?
Click to expand...

On E5 definitely, on E4 we have a better solution with the red box.

ginger bread man said:
And an ecu remap would be the simplest solution of all!
Click to expand...

let me know as soon as you figure that one out ;)
 
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