Unstable rpms

[bobrx3]

If I warm warm up the RX3 and then try to hold a steady rpm (say 4000rpm or 5000rpm) with the bike in neutral, I don't seem to be able to do it. With a constant throttle opening (no motion of the grip) the rpm bounces around. At 5000 rpm it might dip as low as an indicated 4800 and kick high to maybe 5200 and you can hear and feel slight changes in running speed. I can feel this when riding with a very light throttle (holding a steady speed on a flat road). Otherwise the bike runs fine. Accelerates without hesitation or stumbling. As long as I'm speeding up, slowing down or there's a load on the bike (uphill) it feels fine. The bike has only stalled one time at idle, a hundred miles or more ago.

I don't think it started out like this (though maybe I just didn't notice it). I'm at 500 miles. I just did a valve check. It was doing this before the check and the valves were about 0.1mm (wide). I brought them back into spec (0.06mm) and it's still doing it. Resetting the valves seemed to make no difference. I haven't look at the air filter or fuel filter, but at 500 mostly dust free miles neither is likely to be the problem. I don't have a spare plug to swap in, though I do have one on order. I was noticing it on my last tank of gas as well as the current one (bought from different places), so I doubt dirty gas is the problem.

If it had started after I had pulled the tank and adjusted the valves I'd think it was something I'd done, but I'd noticed it before and was hoping the valve adjustment would fix it, but it didn't.

Is anyone else seeing anything like this? I know there have been stalling issues reported and this could be related, but I'm really not seeing stalling.

Before I go digging around in the FI system I just want to make sure that this isn't a characteristic of the RX3 (I can't believe it is, but it doesn't hurt to check). The malfunction indicator light is off and there are no stored error codes.

It could be almost anything. A TPS problem, an injector problem, a fuel pump pressure issue, a CDI issue and so on. I will be contacting CSC on Monday to see what they have to say before digging into the bike, but I'd welcome comments from others who have (or who haven't) experienced similar behavior.

[SpudRider]

Welcome to these forums; we are glad you joined us. :)

My RX3 holds a steady rpm while idling, and while riding. However, I haven't tried to hold a higher, steady rpm using more throttle, while idling. :shrug: I will conduct this experiment sometime later this week. ;)

[katflap]

I have only noticed a very slight surge effect when riding at about 30 MPH @4000 RPM under a neutral load.

I don't think the effect was enough to even register on the Tacho.

I will have a play at 5000rpm on my way to work tomorrow, see if I get anything.:tup:

I think the ECU kicks in to "closed loop" when under a static RPM or neutral load, which uses the O2 sensor for feed back. But I'm just guessing at where the problem could be. :shrug:

:)

[bobrx3]

Thanks for the comments. The slight surging I feel under similar conditions - " riding at about 30 MPH @4000 RPM under a neutral load" doesn't really register on my tach either. The surging seems no worse (in fact it's better) then I used to feel with my V-Strom 650. The rpm fluctuation only really shows up well with the bike in neutral (which is absolutely no load). I'd guess that under riding conditions at neutral load, any surge would create a load and would tend to be slightly suppressed.

I'm also not sure about how sensitive the tach is. When I put a digital tach on there I see fluctuations even when the analog tach looks rock steady (almost like the needle sometimes sticks slightly). Could be mechanical or could be the software they're using to drive the tach.

I'd really like to take a look at the engine parameters while the rpms are not steady. The signals from the TPS, MAP, O2 sensor etc. but I don't have any diagnostics working yet. I've been looking at using a OBDC with bluetooth wired to relevant diagnostic port pins (+v, Gnd, and K-line) but I don't get any data using the Torque app on my Android phone (works fine with my car). I have the Delphi PCHUD software but no hardware connection for it yet. Build or try to buy from China I guess.

[Jay In Milpitas]

Hi Bob,
just pondering your condition, but I'm a novice with EFI so I may be way off track.

Since the O2 sensor senses O2 level in the exhaust stream, have you checked your exhaust pipe flange and the clamp to the muffler for tightness? I haven't noticed if my bike is flippity floppulating under steady throttle, but I had been getting a bit of exhaust popping on deceleration lately, and found those 3 fasteners less than tight. Snugged them all up and no populociousness any more. Wondering if loose head pipe vibrating at certain rpm's could make the controlly box thing think it needs to change the signal to the squirty part?

Have you changed brands of fuel recently? I know that here in the Republik of Kalifornia ARCO has a higher percentage of alcohol (methanol) in their fuel. One of my trucks wouldn't run for beans with it in the tank.

One time after adjusting my valves I had an occasional, sporadic problem with the fuel pump quitting then resuming, manifested by the engine dying and restarting. Under close examination I finally noticed the lock tab on the electrical connector to the pump was touching one of the little bolt heads, preventing the tab from locking as well as not letting the connector fully seat. A couple light passes with a round file on that area of the lock tab solved the problem. Don't know why I hadn't noticed it before.

Good luck in your quest.
Jay

[bobrx3]

Under close examination I finally noticed the lock tab on the electrical connector to the pump was touching one of the little bolt heads

I know exactly the connector to the pump that you mean. There's a bolt that gets in the way of the locking tab. I noticed it taking the connector apart, so I made a special note to check it when I reconnected it. Looks like it must be a common issue!

Headers and pipe connections are tight, so it's not that, but it's an interesting idea to maybe disconnect the O2 sensor and so make the system run open loop. It could be closed loop on partial throttle and open loop on WOT but I don't think that info has ever been provided. That's typically the way these things work though. I know the engine will still run with it disconnected but I haven't checked if it makes any difference to idle or higher rpm stability.

The other sensors aren't part of any feedback loop, so they shouldn't cause instability unless they are generating a noisy signal rather than a constant voltage. I think they are probably required for the engine to run though. Easiest way to measure them would be via the diagnostic port, but the signals could be monitored on an oscilloscope or even using a voltmeter once you can actually get to the appropriate wires.

All the fuel here is the typical 10% ethanol - or at least that's what the pumps claim. I've heard rumors that there's a marina with alcohol-free gas for boats not far from here. More expensive of course but it might be interesting to try.

I'm still hopeful of being able to connect to the diagnostic port. That's really the best way to look at this. If I can't get my system to work I'll have to talk with CSC about getting one on loan for a few days.

Most of all I'm looking for feedback on whether other RX3s do this. If they all do it it's probably a waste of time trying to eliminate it and it could just be a characteristic of this engine.

[Weldangrind]

I haven't noticed if my bike is flippity floppulating under steady throttle, but I had been getting a bit of exhaust popping on deceleration lately, and found those 3 fasteners less than tight. Snugged them all up and no populociousness any more. Wondering if loose head pipe vibrating at certain rpm's could make the controlly box thing think it needs to change the signal to the squirty part?

That's one of the funniest posts I've read in awhile.

[katflap]

Hi Bob,
Tested @ 5000 RPM riding, Neutral load , all fine.

Tested @ 5000 RPM Stationary, fine also, just a little tacho needle vibration. No surging.

Also did 40000 RPM @ £30MPH, as stated in my previous post, no surging here either, so i dont know where i got that from. :shrug:

Regarding data cables, i know some guys in china managed to wire up a regular cable and got it to work.

For myself, i got a dedicated cable from Taobao via Taobaotrends.com agent (see spuds excellent tutorial :tup:)

Though it is bit pricey

https://item.taobao.com/item.htm?id=39520023502

The cable cost $37.70 (£24)

It weighs 0.23Kg

I had mine shipped with some other stuff but if i have worked it out correctly,
i think you could get it mailed for about $6.00 using China or HK post with tracking. :)

[woodlandsprite]

That's one of the funniest posts I've read in awhile.

I agree :) :hehe:

[SpudRider]

...I haven't noticed if my bike is flippity floppulating under steady throttle, but I had been getting a bit of exhaust popping on deceleration lately, and found those 3 fasteners less than tight. Snugged them all up and no populociousness any more. Wondering if loose head pipe vibrating at certain rpm's could make the controlly box thing think it needs to change the signal to the squirty part?...

That's one of the funniest posts I've read in awhile.

I agree :) :hehe:

X3. :lol:

[SpudRider]

Hi Bob,
Tested @ 5000 RPM riding, Neutral load , all fine.

Tested @ 5000 RPM Stationary, fine also, just a little tacho needle vibration. No surging.

Also did 40000 RPM @ £30MPH, as stated in my previous post, no surging here either, so i dont know where i got that from. :shrug:

Regarding data cables, i know some guys in china managed to wire up a regular cable and got it to work.

For myself, i got a dedicated cable from Taobao via Taobaotrends.com agent (see spuds excellent tutorial :tup:)

Though it is bit pricey

https://item.taobao.com/item.htm?id=39520023502

The cable cost $37.70 (£24)

It weighs 0.23Kg

I had mine shipped with some other stuff but if i have worked it out correctly,
i think you could get it mailed for about $6.00 using China or HK post with tracking. :)

As always, thanks for your detailed report, and your willingness to help, Kat. :tup:

[bobrx3]

Thanks Katflap. It's useful info that your bike doesn't seem to do what mine is doing.

I've read your excellent write up on diagnostics. You did a lot of work on that!

Getting the cable via TaoBao looks like a lot of work so I've ordered on of the VW VAG-COM cables. As far as I can tell it's probably a K-line to RS-232 level converter and serial to USB interface so I should be able to talk to it via PCHUD over a com port (assuming I can get it to install in the COM1 to COM4 range). Interfacing to the diagnostic port on the RX3 should be easy as there are only three active wires (+v, Gnd and the K-line). I can a VAG-COM adapter in the US for $6 and it will be here in a few days. Not much lost of it doesn't work!

I have your PCHUD files and a second version of PCHUD I downloaded from a Russian website. Seems to load OK on my XP laptop.

The bluetooth ELM327 interface I have doesn't seem to want to talk to the MT05 on the RX3. I wired it up the the appropriate pins and it powers up OK but I can't get it to talk to me using generic ELM 327 software. Probably doesn't speak proper MT05 language, which may be different from that used in most cars? Even if I could I'm not sure I could easily access all the engine parameters. Works fine on my K-line Subaru though.

I haven't talked with CSC yet, but I intend to give them a call this afternoon and see what they have to say.

[jct842]

On my majesty 400cc scooter it was impossible to hold it at 3000rpm with it on the center stand. Always would slow down or speed up, yet with the wheel on the ground and while riding you could hold 3000 rpm all day long. Seems it just needed a load on the engine. John

[bobrx3]

Thanks for the data point on the scooter. I guess it could be a characteristic of small displacement fuel injected engines with one (or two) cylinders. It's not something I've ever noticed on the carburated bikes I've owned and it's not something I've noticed on any fuel injected cars either.

I spoke with CSC yesterday and they said that they have seen this behavior and it's more noticeable on some bikes than others. It doesn't seem to be associated with any particular fault and running the engine diagnostics doesn't show any particular anomaly. It looks like it could be due to the cumulative effect of a number of small fluctuations. Sensors that may be slightly noisy, tiny intake or exhaust leaks, fluctuations in spark efficiency etc.

I guess what I'll do is to go through the engine checking all the sensor connections and maybe using some contact lubricant on them. I'll replace and maybe index the spark plug (probably with an iridium version), spray around the intake looking for leaks and oil and check the air filter. If all that makes no difference then I'll either live with it or dig into the signals from the sensors looking for noise.

[Adjuster]

I think a nice new NGK iridium plug is going to go a long way for you in smoothing out the bike. Get a couple extra to have on hand. I am obsessive about removing, cleaning and re installing my plug. Bike always runs better with a clean plug, does not need to be new, only cleaned. Be sure to report to us the condition of the plug you are currently running when you remove it.


/

[AZRider]

My money (my .02c worth) is on an air leak at the intake.

[Weldangrind]

It does sound like a minor vacuum leak to me as well.

[SpudRider]

The exhaust header might be loose, as well. The RX3 exhaust system should have been designed with another bolt supporting the midpipe, right before it connects to the exhaust header. I fabricated a midpipe support, and my exhaust header bolts don't loosen any more. :)

http://i442.photobucket.com/albums/qq146/spudrider/Zongshen%20RX3/DSCF3670_zpscoegajv4.jpg (http://s442.photobucket.com/user/spudrider/media/Zongshen%20RX3/DSCF3670_zpscoegajv4.jpg.html)

http://i442.photobucket.com/albums/qq146/spudrider/Zongshen%20RX3/DSCF3680_zps0gjghknp.jpg (http://s442.photobucket.com/user/spudrider/media/Zongshen%20RX3/DSCF3680_zps0gjghknp.jpg.html)

I have since added a short piece of aluminum angle iron for lateral support, and the exhaust system doesn't budge, or vibrate, which tends to loose the exhaust header bolts. ;)

[bobrx3]

Well, checked the exhaust headers again - everything tight. Checked the intake boots and vacuum hoses - no leaks. Oiled the air filter. Installed an iridium plug (indexed). Checked and cleaned connectors for the MAP/MAT and TPS. Checked mechanical mounting of the MAP/MAT and TPS - all tight.

No significant change. I still get rpm surging with the bike in neutral and mid range rpms. I'll take it out for a ride later and see if it feels any different.

Update: No different. Another situation in which the effect is quite noticeable is when trying to ride slowly in traffic, say 10mph in 1st gear. It's difficult to maintain a constant speed due to the surging.

[Jay In Milpitas]

Just curious, Bob, if your software and 'puter can display the ignition advance curve?

My reason for asking is based on experience with points systems using mechanical (centrifugal) advance units. When worn, sticky, sloppy, or springs get weak, they tend to cause erratic rpm, most noticeable when under no or light load just as you describe.

I'm thinking that if the ignition trigger sensor is getting noise or is "thinking" it needs to advance too quickly, it might give the symptoms you have. Make any sense?

[bobrx3]

I do have the computer diagnostics working now. As far as I can see the only advance parameter displayed is the calculated advance, so I can see what the advance should be under any set of conditions but there's no way to measure it. Since it's all electronic and controlled by the EMU, I'm guessing that the advance will, in fact, always be what the EMU calculates it should be. There's nothing mechanical to stick or wear.

Don't see any obvious signs of a major problem from the system measurements. I did switch out the MAP/MAT sensor for another one, but that made no difference. I see fluctuations in the injector opening time and MAP sensor outputs, but you can't really tell if they are the cause or the result of the speed fluctuations. TPS signal is rock steady as it should be. The oxygen sensor output is pretty noisy but I'm guessing it's a narrowband sensor which is VERY sensitive at the lean/rich boundary (which is where it should be) and is basically a lean/rich switch. If it's a wideband sensor then the noise may be significant. I'll have to talk with CSC and see if they know what the signal should look like. I see it rapidly spiking between maybe 100mV and 700mV. I have no idea if this is normal.

CSC have said some bikes seem to do it more than others, but to date no specific cause has been found.

I'm starting to think it's one of those things that might only be cured by a new fueling map which is something beyond my level of expertise. I know some bikes are like this. The DL650 had a pretty bad reputation for surging. I had this thread bookmarked from my days of DL650 ownership! http://www.vstrom.info/Smf/index.php/topic,5935.0/wap2.html

[bobrx3]

Regarding data cables, i know some guys in china managed to wire up a regular cable and got it to work.

For myself, i got a dedicated cable from Taobao via Taobaotrends.com agent (see spuds excellent tutorial :tup:)

Though it is bit pricey

https://item.taobao.com/item.htm?id=39520023502

The cable cost $37.70 (£24)



Just FYI I hacked a VAG-COM USB cable. Cost me $6. Of course you don't get the nice connector but the price was right and it arrived in a couple of days. Works just fine as far as I can tell.

Short writeup here - http://www.rx3adventure.com/rx3_computer_diagnostics.html

[katflap]

Nice work bob :tup:

Its good to know that there is a cheap cable solution that only requires a little soldering.

Regarding the O2 voltage, I would guess 700mv - 100mv is normal.

This is a graph of mine at warm idle.

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[bobrx3]

Nice work bob :tup:

Its good to know that there is a cheap cable solution that only requires a little soldering.

Regarding the O2 voltage, I would guess 700mv - 100mv is normal.

This is a graph of mine at warm idle.



Here's what I see. It's obviously on a different scale of course and it's at around 3000 rpm. The span is around 20 seconds and the vertical axis runs from around 30mV to 840mV. It's not hugely different from what you see I guess. Probably what you'd expect from a narrowband sensor that really only has two effective states, rich and lean.

http://www.rx3adventure.com/images/o2data2.jpg

[bobrx3]

Here's a 50 second snapshot of rpm data with a constant throttle opening (TPS sensor output is essentially a flat line with a few 1 or 2 bit glitches)

http://www.rx3adventure.com/images/rpmdata1.jpg

http://www.rx3adventure.com/images/tpsdata1.jpg

[katflap]

I tried to do a stationary 4000rpm log for you so you could compare readings, this was the best I could do.

I was surprised at how much my rpm fluctuated but I don't think it swings as much as yours.

I held the throttle as still as possible, its position only varied by 0.2% ( see image 2).
Here's a download of my log, I hope it will be of some use to you.
https://mega.nz/#!t4BQ1IDL!KNm0GkxWCN6aEMNHbBmuykhaG4dUw4BMaRsebJE STg8

One thing to bear in mind is that I think that your bikes in the states got an updated ECU . I'm not sure how the readings will differ to my UK bike.

:)
3116

3117

[bobrx3]

I tried to do a stationary 4000rpm log for you so you could compare readings, this was the best I could do.

I was surprised at how much my rpm fluctuated but I don't think it swings as much as yours.


Many thanks for the test and the log. Your log and mine don't differ all that much - except for one thing. I notice that your "Fuel Pulse Width1" goes DOWN from about 3.1ms to 2.7ms when you open the throttle up. That seems wrong. Surely the pulse width needs to go up to supply more fuel? Mine goes UP from about 3.1ms to 3.5ms which is what I'd expect.They both change by about the same amount (0.4ms) but in different directions! Very odd. I think your data for Pulse Width must be wrong since I just can't see how opening up the throttle and increasing the rpm could result in lower fuel consumption.

BTW I get my throttle opening constant by inserting a 1mm shim between the idle speed adjusting screw and the lever that opens the throttle. That takes my shaky hands out of the equation!

We may well have different fuel maps corresponding to different emission requirements in the US and UK but I'd guess they'd be pretty similar. Apart from the pulse width, the changes in the other parameters I've looked at seem pretty similar between the two bikes.

I don't know of any way to access the fuel maps (or change them). Obviously there is a way since somebody must program them (either Delphi or Zongshen), but it's not via PCHUD. I'll have to look at a few of the tuning forums to see what's out there. H-D use the same EMU and there are a lot of H-D tuners. I know HD uses a CAN interface, but the EMU and diagnostic connector on the RX3 does have CAN connections

How does your bike run when trying to hold a constant low speed in traffic, say 10-15mph in 1st or 2nd gear? I get quite a lot of surging. At higher speeds in higher gears with a neutral throttle it gets less noticeable but it's still there if I look for it.

I'm still talking with Gerry at CSC and he's been very helpful giving me things to check that might be causing problems (so far none of them seem to make any difference). He's really starting out as much in the dark as we are about the bike and learning as he goes - but he's getting a lot more experience with them than any single owner so he's building up a knowledge base faster than we are! He's seen bikes with surging issues, but he's either fixed them by swapping out a sensor, or they've gone away after looking over the bike, checking everything and not really finding anything specific. Apparently he's not seeing anything in the diagnostic readouts that points to any particular problem.

I suspect there may be a couple of factors. One is the sensitivity of the rider to surging. Some riders may simply not notice it or register it as an issue. Maybe they're used it it from other bikes or maybe they think it's just how bikes are. The other factor is just how the various "margins of error" in the bike's fueling system and engine/transmission manufacturing tolerances add up. All bikes aren't ever going to be exactly the same.

[katflap]

Many thanks for the test and the log. Your log and mine don't differ all that much - except for one thing. I notice that your "Fuel Pulse Width1" goes DOWN from about 3.1ms to 2.7ms when you open the throttle up.

I hadn't spotted that, I agree it does seem strange. I will have to look in to that .:hmm:


BTW I get my throttle opening constant by inserting a 1mm shim between the idle speed adjusting screw and the lever that opens the throttle. That takes my shaky hands out of the equation!

Why didn't I think of doing something like that :doh: :)



How does your bike run when trying to hold a constant low speed in traffic, say 10-15mph in 1st or 2nd gear? I get quite a lot of surging.

I find that its certainly not the bikes strong point riding at these speeds and traffic conditions and does seem to require a feather light touch to get a smoothish ride. At worst I would describe it as lumpy, for me it doesn't really surge.

That said, remember our bikes in the UK don't have the cush drive.:cry:

Most of my biking experience was over 20 years ago, so I guess some body with more recent riding experience on a range of bikes would be better placed to say whether the RX3 was performing better or worse than other bikes under these conditions. :)

[rjmorel]

Just shooting in the dark here . Does your throttle cable have any slack in it? Some people tighten the slack out for whatever reason and when going over little bumps it tweeks their wrist and the bike responds immediately. On a 525 race bike picking your way through rocks in first gear, that can dump you on you behind real quick.
Could your throttle cable be tight enough for the vibrations to cause it to gyrate rpm's up and down a little? rj

[Jay In Milpitas]

Ah ha! I think Katflap's Fuel Pulse Width goes down because they drive/ride on the left side of the road, so that compensates for the rotation of the Earth.

Bob, I'm thinking that a Blue bike EMU got installed on your Orange Cyclone, wrong side of the color spectrum. So that would make it think it's seeing green when it's really brown.

<Select Serious Technical Font> The reason I asked before about checking ignition advance (mapped & actual) is that on a forum for airhead BMW's that I'm on, some folks have converted from points to aftermarket electronic. At least one conversion has selectable advance programs (via DIP switches) and selecting the wrong curve gives symptoms similar to yours.

Do have access to an exhaust gas analyzer? If the digital signals are all good, then it is possible that the injector may either be spraying poorly which happens to manifest better/worse under these conditions.

The only other Luddite recommendation I have is to recheck all connections and mounting security, including the mount & ground of the ignition coil. I have seen cases where corrosion or loose coil attach points have caused folks to pull hair out until found. Remember that the spark path goes from the coil through the wire to the plug, but returns via the engine, through the frame and then the coil.

Good luck, Jay.

[pete]

wonder if it could be jumping between open & closed loops...

[Jay In Milpitas]

Don't know why I didn't connect these posts earlier.

Bobrx3 and Katflap, meet Riceburner. Rice, meet the tech folks.

http://www.chinariders.net/showpost.php?p=189459&postcount=1

Carb vs. FI, same rpm range. Grab beers and engage.

[bobrx3]

The carb issues sound different. Looks like the carb setup was running rich in a particular rpm range, which is something cured by changing the needle profile and/or the needle height. On an FI bike that's the equivalent of changing the fueling map stored in the EMU.

I don't have an EGA, but the O2sensor should tell me if the bike is running rich or lean and the O2 sensor tells me things are OK. Being a narrowband sensor it's output is either "rich" or "lean" and it bounces between the two (in closed loop) as it would be expected to.

Surging is, I think, something of a common problem with small capacity, single or twin FI bikes. They are never in a steady state like a carburetted bike and the engine doesn't have enough inertia to smooth things out. They are constantly responding to inputs from the MAP, MAT, TPS and O2 sensors, changing the injector opening times to correspond with the fuel map and the sensor input corrections. My DL650 had similar issues. Here's a "tale of woe" thread about surging on the DL650 - http://www.vstrom.info/Smf/index.php/topic,5935.0.html - I think the eventual conclusion was something like "they all do that to some extent", but no definitive diagnostic conclusion. Neither the dealer nor a custom tuner was able to properly fix it. The RX3 may be the same. I'd love to ride another RX3 to see if it's my bike or it's just me that's overly sensitive to the issue. However I doubt there's another RX3 within 500 miles of me. There's certainly not another one anywhere in Maine unless someone has ridden up here on vacation! I think there's one in NY state somewhere. There's also a guy in NH who is looking to get one in the fall. That's one problem with the RX3. If you think have a problem you can't just find another bike to compare it to unless you live near CSC...or you buy two of them.

On light throttle I'm pretty sure it stays in closed loop. The diagnostic readout has the info and I'll take a look. It's not slack in the throttle cable (when testing in neutral at around 3000-4000rpm) because I raise the rpm with the bike in neutral by holding the throttle open with a 1mm shim at the throttle body. The diagnostic readout shows a constant TPS signal. On the road there could be a component due to not being able to keep a constant throttle opening as well as chain slack and cush drive movement, but the fact that the rpm fluctuates in neutral when I know the throttle is fixed and there's no chain or cush drive involvement makes me think it's not 100% a mechanical issue.

Thanks for all the suggestions. I haven't given up since the bike is perfectly rideable. It just bucks and surges a little at low speed in town and surges a little at a constant speed on neutral throttle when I'm trying to hold it at the speed limit in 35-45mph zones. It's annoying but I can live with it if I have to - as long as it doesn't get worse.

I don't think there's any way to see the actual spark advance. That's an output from the EMU, not an input to it, so all you can see is the calculated output signal. You can see the spark dwell time and nothing looks unusual there.

The troubling thing is that I don't remember it doing this when I first got the bike and I was doing the break-in over the first few hundred miles. I con't be sure if it didn't do it or if I just didn't notice it. I've only got around 600 miles on it now, so it's not a matter of something wearing. It was doing it both before and after I checked the valves at 500 miles, so it's not a valve adjustment issue and it's not something I disturbed pulling the tank to get at the valves.

[katflap]

I notice that your "Fuel Pulse Width1" goes DOWN from about 3.1ms to 2.7ms when you open the throttle up. That seems wrong. Surely the pulse width needs to go up to supply more fuel? Mine goes UP from about 3.1ms to 3.5ms which is what I'd expect.They both change by about the same amount (0.4ms) but in different directions! Very odd. I think your data for Pulse Width must be wrong since I just can't see how opening up the throttle and increasing the rpm could result in lower fuel consumption.

I hadn't spotted that, I agree it does seem strange. I will have to look in to that .

I've done a little research,

It would seem that an ECU is capable of adjusting the injector pulse width to accommodate varying battery voltages.
The idea being that the lower the system voltage the longer it takes for the injector to open, thus requiring a larger pulse width to deliver the same amount of fuel.

I ran my test soon after I had started my bike.

I wonder if then at idle my system voltage was running relatively low so requiring quite a large pulse width.
Then when brought up to 4000rpm the magneto was working better, bringing the system voltage higher so enabling the pulse width to be smaller even though it was actually injecting more fuel.

This is the only possible answer I've been able to find so far :hmm:

( Apparently it takes approx. 1 m/s for an injector just to open and close)

[mouradjan]

In Turkey many of Rx3 owners were complaining about unstable rpms and stopping problems.The company Mondial has tried to solve this problem .Now they are changing the O2 Sensors who has these problems in their bike.Now everyone is happy .
I didn't have any stopping problem but sometimes my bike has unstable rpms too.
Today i disconnect the O2 sensor socket and rode my bike.Allday long i had really good time with my bike☺.U should try some day, There is a great power differance. Motorbike is like a monster.Everytime u open the throttle u feel a more agressive bike.There was no unstable rpm anymore.it is now working like a clock.i don't think my O2 sensor has a problem but all rx3 owners who changed their O2 sensor is telling the same thing ,no unstable rpms ,no stopping anymore .I mean without the original O2 sensor and with new bosch sensor ,bike is working verywell. İ guess a better sensor will be a good idea.

[MattyBoy1976]

Old thread, I know, but it addresses my recent experience. I was out riding last week, about 75 miles from home, when I noticed that the bike acted like it was going to die (like it was out of fuel or something). I was running about 50 mph in 5th gear, and starting up a slight grade, so I applied throttle to maintain speed. When I hit the throttle, it "bucked" for lack of a better term-sputtered and then kicked back in. It continued to do this until I got back into cell phone range. The "check engine" light came on and went off intermittently, as well.

When I got to cell phone range, I called Gerry at CSC and he walked me through reading the error code. The code was 0132, which indicates a fault with the O2 sensor. Gerry had me check the connection to make sure it was good, and it was. I rode home, but not easily-I felt like I was killing my poor bike! It would accelerate OK if I was gentle with the throttle, but as soon as I got near 6000 RPMs, it would start "bucking" again. Made it home and parked, and Gerry's sending a new O2 sensor. Hopefully that corrects the issue!

[SpudRider]

In Turkey many of Rx3 owners were complaining about unstable rpms and stopping problems.The company Mondial has tried to solve this problem .Now they are changing the O2 Sensors who has these problems in their bike.Now everyone is happy .
I didn't have any stopping problem but sometimes my bike has unstable rpms too.
Today i disconnect the O2 sensor socket and rode my bike.Allday long i had really good time with my bike☺.U should try some day, There is a great power differance. Motorbike is like a monster.Everytime u open the throttle u feel a more agressive bike.There was no unstable rpm anymore.it is now working like a clock.i don't think my O2 sensor has a problem but all rx3 owners who changed their O2 sensor is telling the same thing ,no unstable rpms ,no stopping anymore .I mean without the original O2 sensor and with new bosch sensor ,bike is working verywell. İ guess a better sensor will be a good idea.

Thank you for letting us know about the O2 sensor problems in Turkey. :)

[SpudRider]

Old thread, I know, but it addresses my recent experience. I was out riding last week, about 75 miles from home, when I noticed that the bike acted like it was going to die (like it was out of fuel or something). I was running about 50 mph in 5th gear, and starting up a slight grade, so I applied throttle to maintain speed. When I hit the throttle, it "bucked" for lack of a better term-sputtered and then kicked back in. It continued to do this until I got back into cell phone range. The "check engine" light came on and went off intermittently, as well.

When I got to cell phone range, I called Gerry at CSC and he walked me through reading the error code. The code was 0132, which indicates a fault with the O2 sensor. Gerry had me check the connection to make sure it was good, and it was. I rode home, but not easily-I felt like I was killing my poor bike! It would accelerate OK if I was gentle with the throttle, but as soon as I got near 6000 RPMs, it would start "bucking" again. Made it home and parked, and Gerry's sending a new O2 sensor. Hopefully that corrects the issue!

Thanks for letting us know about the problem. If anything serious is wrong with the EFI system, the ECU will generate a DTC (diagnostic trouble code). :) As usual, Gerry and the rest of the gentlemen at CSC provided excellent customer service. :tup: