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CBR1000 Misfire
DANMAN - 7/11/18 at 11:25 AM

Hi everyone,

I am having a weird issue where my engine idles ok and if you give it some revs in neutral it will rev freely to say 6k ok once but if you try to rev it again straight away it misfires and farts unless you let it settle for about thirty seconds. It sounds like a fueling issue but the fuel system seems fine.
What I have checked so far (also using the CBR1000 workshop manual):
- Fuel pump and pressure regulator are fine and within spec
- Fuel pump filter is fine as is the additional inline filter which is new and flow direction is correct
- Fuel lines are new and right size
- Tank breather is fine and not blocked
- Tested fuel flow and fuel pressure and both are within factory spec
- New MAP sensor (factory one was reading out of spec)
- New spark plugs
- New fuel
- CMP & CKP sensors tested fine and within spec
- Injectors (all 8) have been flow tested and are all fine
- No intake air leaks
- HISS is bypassed and checks ok
- Speed sensor tests fine and within spec
- Exhaust servo motor is still connected and tests fine
- ECT Sensor is fine
- IAC Sync is fine
- Vacuum lines are fine

Video of issue here: https://www.youtube.com/watch?v=sahP59tS3VM

This stupid problem has got me stumped.


AdamR20 - 7/11/18 at 01:01 PM

What happens if you put it in gear (clutch in)? Wondering if there may be some sort of over rev protection?

AFAIK the neutral mapping is different to in-gear mapping.

[Edited on 7/11/18 by AdamR20]


davspeed - 8/11/18 at 09:33 AM

It's a bit difficult to hear it properly from the clip but I have put a similar engine (2007) in my striker and don't have that problem. My problem is light throttle running is very jerky like it needs the choke on in old carbed cars, a dyno session will hopefully sort that.
How have you done your air intake as I see you have a foam filter.


DANMAN - 8/11/18 at 10:04 AM

quote:
Originally posted by AdamR20
What happens if you put it in gear (clutch in)? Wondering if there may be some sort of over rev protection?

AFAIK the neutral mapping is different to in-gear mapping.

[Edited on 7/11/18 by AdamR20]


I have tried driving it and it dies and runs like a dog once there is any load on the engine, I can move it up and down the driveway if I keep the revs under about 2500rpm but outside of that it dies like it is running out of fuel.

Interesting point though about the idle maps being different, I would like to try and get confirmation on this as the neutral wire does feed into the ECU via the clutch diode when the engine is in the bike. I bypassed the clutch diode, side stand switch, etc as they obviously weren't required but I figured the input to the ECU was only there to stop it from starting without the clutch pulled in, side stand up or the engine in neutral.

Has anyone got a car edited version of a CBR1000 wiring diagram? I just worked through the harness myself culling and bypassing the stuff that wasn't required but maybe I ar$ed something up?

[Edited on 8/11/18 by DANMAN]


DANMAN - 8/11/18 at 10:20 AM

quote:
Originally posted by davspeed
It's a bit difficult to hear it properly from the clip but I have put a similar engine (2007) in my striker and don't have that problem. My problem is light throttle running is very jerky like it needs the choke on in old carbed cars, a dyno session will hopefully sort that.
How have you done your air intake as I see you have a foam filter.


There was no way I was going to fit my engine under the bonnet with the factory air box and throttle bodies in the normal location so I have to lay them over:

https://i.imgur.com/lwGQdBq.jpg

This obviously increased the intake runner length from the tip of the trumpets to the back of the valves so to get it as close to factory as I could I had to make a new set of shorter trumpets and secondary injector bracket set up. I have kept the distance and angle of the secondary injectors from the trumpet mouths the same as factory dimensions:

https://i.imgur.com/TMLZStZ.jpg

I then built a new air box to encompass all of this with the same volume as the factory airbox (yes I sealed off the factory air box with various plates so I could fill it with water to find the total volume):

https://i.imgur.com/F9hkOF0.jpg

There are no intake air leaks anywhere that I could find.

[Edited on 8/11/18 by DANMAN]


AdamR20 - 8/11/18 at 10:44 AM

quote:
Originally posted by DANMAN
Interesting point though about the idle maps being different, I would like to try and get confirmation on this as the neutral wire does feed into the ECU via the clutch diode when the engine is in the bike. I bypassed the clutch diode, side stand switch, etc as they obviously weren't required but I figured the input to the ECU was only there to stop it from starting without the clutch pulled in, side stand up or the engine in neutral.

Has anyone got a car edited version of a CBR1000 wiring diagram? I just worked through the harness myself culling and bypassing the stuff that wasn't required but maybe I ar$ed something up?

[Edited on 8/11/18 by DANMAN]


I have the Woolich Racing software and there is a different neutral map (and different maps per gear and per cylinder too!).

Don't have an edited car loom but have standard Honda diagram and a 'guide' for what to chop out if any use?

[Edited on 8/11/18 by AdamR20]


jossey - 8/11/18 at 01:57 PM

Crank position sensor


davspeed - 8/11/18 at 03:00 PM

Interesting way of doing it, I tried the original air box on my striker and it was worse than an old school hot rod with a massive blower on it so did it like in the pic below. it may not be perfect but at least I can see where i'm going.

2018092 7_152409 by david.vangils, on Flickr

[Edited on 8/11/18 by davspeed]

[Edited on 8/11/18 by davspeed]


davspeed - 8/11/18 at 03:08 PM

quote:
Originally posted by AdamR20

I have the Woolich Racing software.


[Edited on 8/11/18 by AdamR20]


How do you find the woolich racing stuff? I have only become aware of it in the last couple of weeks I have PC5 but woolich sounds more comprehensive. Are there any four wheel dynos that use it only seen bike dynos for it.