39 replies to this topic

[Catteeclan]

I am following this with great interest as the smoothing of throttle response will greatly improve the 9er.

Me too. 

[fixitsan]

I am following this with great interest as the smoothing of throttle response will greatly improve the 9er.

 

What I know so far is that you can go ahead and ground the neutral switch wire to cancel fuel cutting. You don't need to even disconnect the neutral switch first, as far as I can tell, if you just want to try it out temporarily to see if you feel it helps with riding smoothly

 

The negatives are that the neutral light will always be on, and starting the bike in gear might be possible without pulling the clutch in.(but if you know it's in neutral, it won't be an issue)

 

I'm just this moment looking at a bypass relay. A cheap module from ebay, with a built in timer and a relay - as long as the module gets pulses from the front sprocket sensor (or wheel speed sensor on an ABS equipped bike) it will deactivate the neutral lamp circuit, by keeping it open to extinguish the neutral lamp while the bikes moves forwards. This would need connections to at least 2 wires in the harness, as well as 12V, and GND. By adding another wire connection it could be made so that it automatically disconnects the neutral grounding wire circuit if the engine isn't running, meaning that starting up would be the same as it is now, with no risk of starting while in gear.

 

I might make something myself though. It would need to be 'optically isolated' for safety, this means that only a miniscule amount of current is taken from the host circuit in order to read the sensor, without any risk of shorting it out while riding .

 

When I come up with a fix which is a bit more elegant than a piece of black tape over the neutral indication lamp I'll post a message about it here. But for now I'm going to live with a simple switch while I have a think about

Edited by fixitsan, 30 September 2024 - 09:30 am.

[fixitsan]

I've just ordered one of these. It has the time delay, the 5V pulse input, and optical isolation all together on one PCB.

 

If it works it's a cheap fix !

 

https://www.ebay.co....emis&media=COPY

[fixitsan]

I got another 70 miles of play over the weekend, and I'm convinced that riding is much smoother and easier with the neutral switch grounded.

 

I haven't got much further with making something to automate it, but a simple switch works fine for now

[Coxylaad]

I messed about with overrun fuel cut on my 900 with the standalone ecu.  I found that adding fuel on the overrun at high rpm made no discernible difference, but lower that 3500rpm and pushing a small amount of fuel into the bores made a big difference to how the bike behaved from a closed throttle. It ended up feeling like a really nice carb setup once I had it dialled in. 

 

this is next level though ^^ 

[fixitsan]

I messed about with overrun fuel cut on my 900 with the standalone ecu.  I found that adding fuel on the overrun at high rpm made no discernible difference, but lower that 3500rpm and pushing a small amount of fuel into the bores made a big difference to how the bike behaved from a closed throttle. It ended up feeling like a really nice carb setup once I had it dialled in. 

 

this is next level though ^^ 

Oh no not now it isn't !

 

It's a just a switch to ground the neutral switch out at the moment. Works a treat

 

But what I've ordered to play about with is a small accelerometer, so that it will detect braking and just act when decelerating. And as soon as the bike comes to a stop the neutral switch and neutral light will behave as normal

 

But I don't know how to turn off the neutral light on the dash when it activates _without cutting the harness_.

I might just install a bit of tinted film over the neutral light so it can still be seen if you look at it, but it just won't be as bright as normal.

[Snowbird]

Just had a quick glance at a 900 wiring diagram and it looks like the offending link to remove may be shown here between starting cut off relay and ecu, try it with the black/yellow wire removed from ecu connector plug and insert a new grounded terminal so ecu thinks it's in neutral but neutral light still works as normal, will likely mean side stand switch won't operate anymore and you can start in gear with stand down but we all survived for years without that function I'm sure.

 LOOM.jpg   171.54KB   1 downloads

[fixitsan]

Just had a quick glance at a 900 wiring diagram and it looks like the offending link to remove may be shown here between starting cut off relay and ecu, try it with the black/yellow wire removed from ecu connector plug and insert a new grounded terminal so ecu thinks it's in neutral but neutral light still works as normal, will likely mean side stand switch won't operate anymore and you can start in gear with stand down but we all survived for years without that function I'm sure.

LOOM.jpg

 

Thanks for clarifying. I only gave it a brief look and thought the wire from the ECU went to the L/Y wire, spent a few hours scratching my head, then a closer look with the correct glasses showed there is no dot on the crossover of those wires !

 

I'll just go give that a try...

[Catteeclan]

Just had a quick glance at a 900 wiring diagram and it looks like the offending link to remove may be shown here between starting cut off relay and ecu, try it with the black/yellow wire removed from ecu connector plug and insert a new grounded terminal so ecu thinks it's in neutral but neutral light still works as normal, will likely mean side stand switch won't operate anymore and you can start in gear with stand down but we all survived for years without that function I'm sure.

LOOM.jpg

That's the early 2002 model same as mine and is exactly what I was thinking.

[fixitsan]

Just had a quick glance at a 900 wiring diagram and it looks like the offending link to remove may be shown here between starting cut off relay and ecu, try it with the black/yellow wire removed from ecu connector plug and insert a new grounded terminal so ecu thinks it's in neutral but neutral light still works as normal, will likely mean side stand switch won't operate anymore and you can start in gear with stand down but we all survived for years without that function I'm sure.

LOOM.jpg

 

 

T H A T   W O R K S  

 

I cut the black/yellow wire about 2 inches from the ECU plug, grounded the ECU side and there's now no fuel cut. If left ungrounded then fuel cut happens .

 

A N D

 

You can't start it in gear. the stand-down function works exactly the same too.

 

A N D

 

The neutral light works as normal

 

A perfect solution !

Many Thanks Snowbird !

Edited by fixitsan, Yesterday, 05:58 pm.

[fixitsan]

This is the Black/Yellow wire...

 

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I made up this wire...

 

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Attached a terminal at the ECU side...

 

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Cleaned the front screw of the left ignition coil, sprayed with terminal cleaner/lube and added a star washer

 

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The wire in position, terminals sprayed with chain wax to keep the water out...

 

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There is also at least one ground wire at the same ECU plug as the black/yellow wire, which would work just as well

Edited by fixitsan, Yesterday, 07:00 pm.

[fixitsan]

Adding a switch would be relatively easy

 

 switch.jpg   24.15KB   0 downloads

[Snowbird]

Nice one! Not bad for 10 minutes with a wiring diagram, although without the knowledge of the neutral behaviour there would be no reason to go down that route.

I assume the ecu connector is not a proprietary plug you could get along with a socket to make an inline plug-in version.

[fixitsan]

Nice one! Not bad for 10 minutes with a wiring diagram, although without the knowledge of the neutral behaviour there would be no reason to go down that route.

I assume the ecu connector is not a proprietary plug you could get along with a socket to make an inline plug-in version.

 

I think it's a special fit plug,  I did think that maybe I should  make a black epoxy filled box, call it a 'special' name, make miraculous claims about it, and sell it at a premium, for what consists of only a Scotchlok splice in a box

 

I've consoled myself already with a couple of beers over losing a few hours on coding, when all along the K.I.S.S. principle won the day. Like you say it did lead to some useful info in the end though

 

I wonder about other bikes from the same period, I know this family of ECU was fitted to a lot of other bikes, including a few Suzuki's. Obviously the ECUs are built to a performance spec with behaviours that need to sense certain situations like 'is the bike in neutral'.

 

Anyway, the sun is out, and I don't start work until 4.30pm, I'll try to fit a ride in today just to confirm there's no fuel cutting. The only testing I've made so far was on my old '04 900 on it's centre stand in the garage.

Edited by fixitsan, Today, 08:31 am.

[fixitsan]

Satisfactory road test !

 

I headed out for an hour towards West Linton - Dolphinton where I knew the back roads would be damp, have a few wet leaves and mud on them.

 

I wasn't disappointed

 

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Riding through bends, normally a lift on the throttle might feel like the back end could break away due to the harsh fuel cut, but now it feels very manageable, you're able to lift off the throttle mid corner and ride smoothly along

 

I think pillion passengers will also feel the benefit because the transitions between  on-off throttle are so much smoother that they're less likely to headbutt the back of your helmet !.

 

 

 

 

[trevini]

Top Job Chris and Snowbird.

 

Am I right in thinking there's a torque restriction on niners in 1st or 1st and 2nd gears? If so, does it also have any affect on that?

Edited by trevini, Today, 10:44 am.

[fixitsan]

Top Job Chris and Snowbird.

 

Am I right in thinking there's a torque restriction on niners in 1st or 1st and 2nd gears? If so, does it also have any affect on that?

 

Trev I'm not sure about it really.

 

I know the 850 had I think 2nd/3rd restriction, based on the gear position switch, but it could only have possibly affected the ignition timing as the carbs are independent.

 

The Samios remap I got for my first niner claimed to remove any torque limiting in lower gears. I know it exists on a lot of bikes to keep the bikes safer for riders with low levels of experience. What I don't know is how or if it is implemented, but I would be guessing to say grounding this wire removes it.

 

The Samios remap also defeated fuel cutting, and thats when I learned how much nicer it made the bike to ride, so that's why I came to look really closely into it

 

So the suggestion of a torque limiter comes from Samios, plus what we know about some other bikes. Only a rolling road test, or maybe a measured 0-60, or 'roll on' type speed test would confirm it

 

My bike has a Power Commander 3  (and +4 deg ignition advance) so it's already getting a bit extra assistance. I think it's perkier after this wire mod, but that's subjective based on the fact I don't feel I'm using as much throttle as before to have the same amount of fun, and also the roads were wet so I wasn't giving it full beans all the time.

 

The only downside I can think of is that extra fuel is being burnt. It may cost 0.05p per mile more now, but it depends how much time you spend slowing down.

 

Another thing I discovered while testing in the garage is that fuel cut is inhibited when the engine is cold and doesn't come into effect until the temperature gauge needle is about 5mm off the bottom position.During this time the idle is a little bit higher than normal too because of the cold start device on the engine, but if you've ever felt that the bike seems a bit smoother when slowing down with a cold engine, then that's what it feels like to me all the time now.

 

Coming back home I got into a bit of slower traffic, and it also helped me there by making it easier to modulate my speed in small amounts and creep along with the traffic.

Edited by fixitsan, Today, 11:08 am.

[trevini]

All interesting stuff. It may not have a negative affect on the economy. Mine was feeling ever so slightly flat off idle on very light throttle openings, so I bumped up the co on the dash by 1 on either cylinder. Flat spot gone and economy has improved by about 3 mpg. Go figure! Fyi, it's never really been changed in the last 10-12 years or so as it's never caused any concern at all and has been running nicely ever since I bought it in 2005. It's very consistently giving 63-68 mpg with an all time low of 55 and a best of 70 in the last two years. My normal riding I would describe as brisk and usually run it in the 4-6k rpm band, so very much where the torque is.

[fixitsan]

All interesting stuff. It may not have a negative affect on the economy. Mine was feeling ever so slightly flat off idle on very light throttle openings, so I bumped up the co on the dash by 1 on either cylinder. Flat spot gone and economy has improved by about 3 mpg. Go figure! Fyi, it's never really been changed in the last 10-12 years or so as it's never caused any concern at all and has been running nicely ever since I bought it in 2005. It's very consistently giving 63-68 mpg with an all time low of 55 and a best of 70 in the last two years. My normal riding I would describe as brisk and usually run it in the 4-6k rpm band, so very much where the torque is.

That's good, I need to play about with the CO on this latest bike because it does bog a little coming off idle, now and then, it could be the PC3 map, but it's easy to add a few more revs.

 

I think in general if you're at peak torque rpm then you're at the most efficient speed, making the most cylinder pressure for the least amount of fuel possible. (give or take a bit)

[trevini]

That was my thinking.