In 2006, Honda made changes engine management in order to meet Euro-3 emissions regulations. Everyone knows about the changes to the VTEC on and off points but they also made other changes. One changes made to help pass emissions was to make fueling changes depending on gear. The ECM determines the gear by comparing the output shaft speed to engine RPM. Keep in mind the ratios between gears get smaller as you work you way to 6th.
Now, if you change your sprockets and do nothing to fix the speedo, then the relationship between output shaft and RPM has not changed and all is well. However, if you add a speed correcter, you've changed the relationship. Once you get to a certain amount of correction, you're going to have a problem. I've checked with several members with '06-'08 bikes and the tipping point seems to be about -10% and above (more negative number). At that point when you go from 2nd to 3rd, the ECM thinks you went to 4th. When this happens the bike runs very bad a light throttle, surges really bad. I have a '06 and currently have a PCV with Autotune and I know from looking at the data when I download, 4th gear at light throttle, is very lean. I'm guessing it's an emission testing area.
Also, I should note that altering the speed signal before it goes into the ECM might affect the ABS system. I don't know this for sure but I think it should be a concern. After all you paid $1000 for ABS, it would be a shame to "break" it with a speed convertor. Again, I don't know this for sure. If anybody does, please let us know.
If you what your speedo to read correct, not all hope is lost. I have done the research and can tell you how to make your corrector work. I'm not going to go into the details because there are a couple different correctors out there, but here's the theory.
The speed signal is taken off the output sprocket with the speed sensor. There is a pigtail off the sensor with a connector that's in the bundle with the O2 sensors. It's at this connector that the speed corrector will intercept the signal, alter it, then send it on it's way like nothing happened. The signal then travels up the side of the bike just inside the frame to the steering head, just under the tank, where there is a factory splice. The signal now has two legs, one goes to the ECM, and the other to the gauge cluster. The gauge cluster wire goes through a gray connector on the left side of the bike behind the side cover, just before the fairing. It's right next to a blue one, you can't miss it. The wire that your looking for is the pink one.
Note: My bike is ABS so if yours isn't, you won't see the valve on the right of the picture.
[image: Posted Image] Speedo Correction Wiring, left fairing. New wire attached to the pink lead going into grey connector
The object is to, at the sensor plug, split the signal. Send one feed to the "stock" signal bike wire so it gets to the ECM, then send the other feed to the input of the speed corrector. Next, extend the corrector output to the pink wire just before it goes into the gray connector. You must cut the pink wire, connect the extended wire to the pink wire before it goes into the connector. The other end of the pink wire most be protected from water and metal contact since it still has the "stock" signal on it. Liquid tape works good for this. You'll will have to look at how your corrector connects to determine which is the input and which is the output. Also keep in mind most correctors I looked at also power the power from the speed sensor to power the corrector. If you need help figuring out the wiring for your corrector, PM me with the model info and I'll figure it out for you.
[image: Posted Image] Speedo Correction Wiring at sensor plug location.
[image: Posted Image] Speedo Correction Good mounting location.
glad you figured out what the issue was on your bike. i have an older model with speedohealer, so never saw the reaction you were seeing.
i would not "think" ABS would be impacted as ABS is a relationship between the two tires' speed and is based off of the ABS ring sensor sending back a pulse. it should not care what speed the ecu thinks the bike is going as long as the two tires' speeds are the same....but i could be wrong. :biggrin:
I have not noticed an issue on my 07 and I have -18.5% correction as I corrected the factory error as well.
Having said that I can confirm that the ECU is reading the speed from the sending unit. I had the connection for the speedohealer come lose which turned off the speedo and my FI light came on and went into limp mode.
Also it you have access to a dyno you could check this but just switching between the A and B modes on your healer.
BTW I have the ABS also and I've tripped it and it still works perfectly....so I dont think thats a worry. The Abs reads the speed of each wheel and if it detects a difference then it trips. The only thing "might" be it doen't avtivate until sooner or later due to the 6 mph threshold
Question could you not just correct this with a PCV or PCIII?
I have not noticed an issue on my 07 and I have -18.5% correction as I corrected the factory error as well.
Having said that I can confirm that the ECU is reading the speed from the sending unit. I had the connection for the speedohealer come lose which turned off the speedo and my FI light came on and went into limp mode.
Also it you have access to a dyno you could check this but just switching between the A and B modes on your healer.
BTW I have the ABS also and I've tripped it and it still works perfectly....so I dont think thats a worry. The Abs reads the speed of each wheel and if it detects a difference then it trips. The only thing "might" be it doen't avtivate until sooner or later due to the 6 mph threshold
Question could you not just correct this with a PCV or PCIII?
This seems really strange because I've talked (typed) to several people with '06-'08 with speed correctors and they all have had this same problem.
Try this. In a res area, at 4000 rpm shift into 3rd and give it real light throttle. If you can find a slight downhill, the kind where you just have crack the throttle, better yet. After you do this, zero out the speedohealer, and try it again. I'm pretty sure that you're going to really notice a problem. If you don't please let me know, you'd be the first.
Alot of people don't ever let the RPM get that low, so they don't notice the problem. I came from riding a ZRX1200 and I'm used to sneaking through the neighborhood at low RPM, it had tons of low end power.
I didn't have a the PCV back then and the PCIII doesn't have separate gear maps. When I made the PCIII rich enough to "fix" the problem, it made the throttle "dead" at light throttle cruise in 4th, 5th and 6th.
Like I said, I'm not sure about the ABS but I know it checks wheel speed against bike speed when you first move after starting. I'm not sure if this is the only time or not, but wired the way I've talked about above will make sure that the corrector is not causing any problem. I'm thinking "better save than sorry".
Fascinating, help me out here though, I dropped a tooth in front and am running about a -11.1 correction to adjust for the gear AND the manufacturer's offset (typically -5.6). If I just adjust for the gear change at -6.5%, do I manage to avoid triggering this ECU issue. I would think the ECU would need to have significant forgiveness in its gear calculation for mere tire wear. From new to bare you can lose 3-4%.
I can certainly live with the manufacturer's built in error knowing I have only adjusted for my gear adjustment (-6.6%) and avoid triggering this condition versus a lot of futzing with the harness. Will this work?
Thinking about it, I found my problem when I corrected for -1 in front. I had a correction of -11.8 (gear to error). The other people that either had this problem or I convinced to test for me, all were in the -11 to -12 window. You're at -18.5 which might make your gear error different. Keep in mind the difference between ratios gets smaller as you go up gears. You may going from 1st to 2nd with the bike thinking you're in 3rd. With the greater correction, you'd be hitting the tipping point earlier. Looking at my data, the difference between 2nd and 3rd in low RPM / light throttle is very small, if any. I was dealing difference between 3rd and 4th which is a pretty big change when looking at that same map window.
If don't find the problem @-18.5, could you please try -12. Thanks for adding to the info exchanged here.
Another reason to just keep doing fuzzy math in my head as I ride.
Subtract 10 or 15% from indicated speed. :rolleyes:
I'm still waiting for an "opportunity" to try it as an excuse for speeding.
I'm not sure how fast I was going, officer. This dang speedometer isn't accurate...... :goofy:
Fascinating, help me out here though, I dropped a tooth in front and am running about a -11.1 correction to adjust for the gear AND the manufacturer's offset (typically -5.6). If I just adjust for the gear change at -6.5%, do I manage to avoid triggering this ECU issue. I would think the ECU would need to have significant forgiveness in its gear calculation for mere tire wear. From new to bare you can lose 3-4%.
I can certainly live with the manufacturer's built in error knowing I have only adjusted for my gear adjustment (-6.6%) and avoid triggering this condition versus a lot of futzing with the harness. Will this work?
The gear calculation is taken between engine RPM and output shaft speed. The change in tire size will change your overland speed compared to your speedo but will have no effect on what the ECU sees as speed, which isn't really your over land speed, just the speed of the output shaft.
6.6% will more the error up in the gears, but I'm not sure if it's enough to make the ECU think you went to 6th when really you went to 5th. Best bet, rewire it.
Somewhere there is math to firgure this out. Maybe I'll get a chance next week. My PCV uses the same method to figure gears, maybe I'll rewire it to get feed after the speedohealer and play with it and find out what the points of tripping really are for each gear change.
ABS triggers at a specified difference in speed between the front and rear tires.
Front tire speed detected by the sensor ring will always be in the same ratio to
ground speed with some variation due to tire circumference and related wear.
Rear tire ground speed is detected at the drive sprocket sensor and will vary in
direct proportion to sprocket changes.
How much effect this will have on the VFR ABS is not known. If the ABS triggers at
'near' lockup (Bonneville SSEi) the effect is likely negligible.
Haven't had a chance to do the +11% check on my 05 yet, it is running well
with a 7% correction.
(finally finished the #@%%&* roof, more time for ole Silver now)
Adrian
ABS triggers at a specified difference in speed between the front and rear tires.
Front tire speed detected by the sensor ring will always be in the same ratio to
ground speed with some variation due to tire circumference and related wear.
Rear tire ground speed is detected at the drive sprocket sensor and will vary in
direct proportion to sprocket changes.
How much effect this will have on the VFR ABS is not known. If the ABS triggers at
'near' lockup (Bonneville SSEi) the effect is likely negligible.
Haven't had a chance to do the +11% check on my 05 yet, it is running well
with a 7% correction.
(finally finished the #@%%&* roof, more time for ole Silver now)
Adrian
I've had a couple people with '04's report no problem. Seems that map-by-gear didn't start 'til '06, through you'd be the first '05 to report. Please use -12 (note negative, not positive) if you could please.
By the way, my '06 has a rear wheel speed sensor attached to the rear disc. Your '05 doesn't have one? Hummm
ok I didn't notice anything unusal at 3000-4000 rpm's however I did notice something wierd at like 5900. It's like it runs out of gas for just a second. so it might be running really lean there.
ABS triggers at a specified difference in speed between the front and rear tires.
Front tire speed detected by the sensor ring will always be in the same ratio to
ground speed with some variation due to tire circumference and related wear.
Rear tire ground speed is detected at the drive sprocket sensor and will vary in
direct proportion to sprocket changes.
How much effect this will have on the VFR ABS is not known. If the ABS triggers at
'near' lockup (Bonneville SSEi) the effect is likely negligible.
Haven't had a chance to do the +11% check on my 05 yet, it is running well
with a 7% correction.
(finally finished the #@%%&* roof, more time for ole Silver now)
Adrian
I've had a couple people with '04's report no problem. Seems that map-by-gear didn't start 'til '06, through you'd be the first '05 to report. Please use -12 (note negative, not positive) if you could please.
By the way, my '06 has a rear wheel speed sensor attached to the rear disc. Your '05 doesn't have one? Hummm
Well paint my face RED :blush: just went outside (nice and cool finally) crawled under old Silver and there they were
hydraulic lines and a jacketed set of sensor wires going to you guessed it, a sensor and ring. soooo.
Looks like there would be no interaction between the speedo healer and ABS since data is read
at the wheels for the ABS.
Ok like you said minus 12 (that's what I meant to say)
ok I didn't notice anything unusal at 3000-4000 rpm's however I did notice something wierd at like 5900. It's like it runs out of gas for just a second. so it might be running really lean there.
Running-out-of-gas is a good way of describing the problem. It would seem that the increased correction that you're running (-18.50) moved it to a higher RPM, or? Try setting it to zero and see what happens.
Well paint my face RED :blush: just went outside (nice and cool finally) crawled under old Silver and there they were
hydraulic lines and a jacketed set of sensor wires going to you guessed it, a sensor and ring. soooo.
Looks like there would be no interaction between the speedo healer and ABS since data is read
at the wheels for the ABS.
Ok like you said minus 12 (that's what I meant to say)
I did crack open the service manual and it does show a input of bike speed to ABS but it doesn't show lack of signal as being a error that will trip the ABS trouble light. It would seem that it only uses this input to trigger the self test.
So I did used a gearing calculator to create the RPM to Speed calculation chart for stock and then down a tooth. Indeed at a 10 to 11 % difference, you hit a point where the rpm to output shaft results in a match that would indicate a higher gear.
Up to about 6-7% the difference is so small there's no way the output shaft to RPM map in the ECU would get the gear assumption wrong by looking at the speed calculation (its only off 2-3 kilometers at the most).
I added a PC III but still noticed a little surging in third gear at 4-5K on sustained riding with a light throttle. My speedohealer correction was set at -11.1, I stopped compensating for the factory offset and set it to -6.2 just for the gear change I did. Its perfect now. I suspect the mapping that Honda added in 2006 onwards already compensated for the factory offset. So if the ECU is already applying a -6.7 for fuel map adjustment purposes and I set it to -11.1, its really now at -17.8 which would definitely through off the ECU's gear calculation.
Anyways, the new setting works great, so no rewiring for me, I am not a big fan of hard wiring permanent changes, I suggest if anyone does do this they add plug splices so they can easily remove the speed corrector without getting out the soldering gun again.
BTW IF the ABS was dependent on the output shaft signal, the ABS light would come on when you disconnect the sensor.
Thinking about it, I found my problem when I corrected for -1 in front. I had a correction of -11.8 (gear to error). The other people that either had this problem or I convinced to test for me, all were in the -11 to -12 window. You're at -18.5 which might make your gear error different. Keep in mind the difference between ratios gets smaller as you go up gears. You may going from 1st to 2nd with the bike thinking you're in 3rd. With the greater correction, you'd be hitting the tipping point earlier. Looking at my data, the difference between 2nd and 3rd in low RPM / light throttle is very small, if any. I was dealing difference between 3rd and 4th which is a pretty big change when looking at that same map window.
If don't find the problem @-18.5, could you please try -12. Thanks for adding to the info exchanged here.
thanks to coderighter for this write up.. helped me lots with my install..
and BTW, for those that don't buy the Speedohealer harness and decide to solder the wires for power, ground and signal in.. the BLACK wire is power NOT GROUND..
I found out the hard way.. :blink: :blink: I was too lazy to get off my ass and get the mulitmeter and ASSUMED the black was ground.. and yes, I let a little smoke out the speed sensor :biggrin: :biggrin:
OK... here is my question. Let's start at the top. Do I have the right speedohealer? lol.
Next, The pigtail that comes from the Speedohealer has two sides. Can you assist me in exactly what I am supposed to do with both sides? The write up is pretty good, I just want to be exact in what I am doing. I am not teh best electrical guy so I get nervous on electrical jobs.
Next, I have this spiral wire going behind the instrument cluster as you can see it wrapped up. (the excess) am i supposed to leave that connected or disconnect?
Next, is that the connector I am supposed to splice in to up top?
Any additional advice you can give me based on my bike and pics would be great. I have an 07 btw. What guage wire did you use? some of those wires seem awful thin.
OK... here is my question. Let's start at the top. Do I have the right speedohealer? lol.
Next, The pigtail that comes from the Speedohealer has two sides. Can you assist me in exactly what I am supposed to do with both sides? The write up is pretty good, I just want to be exact in what I am doing. I am not teh best electrical guy so I get nervous on electrical jobs.
Next, I have this spiral wire going behind the instrument cluster as you can see it wrapped up. (the excess) am i supposed to leave that connected or disconnect?
Next, is that the connector I am supposed to splice in to up top?
Any additional advice you can give me based on my bike and pics would be great. I have an 07 btw. What guage wire did you use? some of those wires seem awful thin.
Thank you sir.
Well, it appears you have the right Speedohealer.
Unfortunately I'm on vacation and not near the bike and/or the manual for the Speedohealer. I don't have all the wiring memorized, have to get back to you when I return in a couple weeks. Since you have the manual and bike available, is there someone you could bounce the info in this post off of?
Does anyone know a source for connector contacts for VFRs? [...] I just need to find a part number or source for these connector
contacts.
Hey DanY1, what did good 'ol Tighwad say? I'm thinking the same thing you are - work up a mod that doesn't involve hacking up the factory wiring.
Hey coderighter (thanks for the BMC filter, BTW), even though my Speedohealer is only making an 8% correction for my stock setup, is it possible that the bike will behave better if I make the mod you've suggested? Even small gains in ridability at small throttle openings are welcome. I do annual starter valve syncs and have a PCIII+O2elims both of which have gone a long way to making the bike behave nicely. If doing this mod would help in even the slightest way, I'd do it. Maybe the ECU is happier all around with the stock signal inputs.
Does anyone know a source for connector contacts for VFRs? [...] I just need to find a part number or source for these connector
contacts.
Hey DanY1, what did good 'ol Tighwad say? I'm thinking the same thing you are - work up a mod that doesn't involve hacking up the factory wiring.
Hey coderighter (thanks for the BMC filter, BTW), even though my Speedohealer is only making an 8% correction for my stock setup, is it possible that the bike will behave better if I make the mod you've suggested? Even small gains in ridability at small throttle openings are welcome. I do annual starter valve syncs and have a PCIII+O2elims both of which have gone a long way to making the bike behave nicely. If doing this mod would help in even the slightest way, I'd do it. Maybe the ECU is happier all around with the stock signal inputs.
I'd set the correction back to 0%. If it runs better, than rewire it. If it runs the same, put it back to 8% and don't worry about it.
Jon, I'm revitalizing this thread. Tonight I rewired my SpeedoHealer as you suggested. I do feel better about the concept that the ECU will now be getting the stock unmodified signal as it was designed to do and the corrected SpeedoHealer signal now runs just to the instrument panel and speedometer.
So, first of all, a huge thank you to Jon (Coderighter) for his excellent research on this and for sharing his great solution. The only thing I did differently is that I removed the pin from the instrument side of the light grey connector and soldered my new wire directly onto the upper part of the pin contact where the original pink wire is crimped. This way I can remove the heat shrink tubing, desolder my added wire and return the pin contact into the grey connector and restore the factory wiring.
My concern is, having now split the speed sensor signal into the ECU and the SpeedoHealer, if this signal is not designed for a high impedance input, I have just increased the load on this signal. I mean, if the speed sensor's output is a whimpy hall effect type signal that requires special receiver circuitry for amplification etc., then I have just seriously compromised the circuit and, hence, the reliability.
Now I am inclined to research the speed sensor and what type of signal it generates. The Honda FSM refers to it as the VSS (vehicle speed sensor). It is maybe a magnetic field anomaly detector or similar. It doesn't touch anything but rather is positioned very close to the front sprocket's teeth and detects them as they whir around. As such, it seems to be a rather delicate signal. Power is applied to the VSS, along wi reference ground, and it generates a modulated gentle signal of some sort.
I wonder how delicate this signal might be and whether it might be affected by the apparent load of the SpeedoHealer's corresponding signal input circuit which, like the ECU, would be designed to amplify this wonky special signal of the VSS.
Meh, that's just the anal retentive electrical engineer part of me over analyzing and worrying. Bottom line is, if it works, it works! I'm gonna have two fingers of scotch right now to calm myself down :-)
As a follow up to this, I'm glad to report that many thousands of kilometers later, this mod is working fine for me. My concern - stated in previous post - over splitting the signal and creating an additional load on the VSS is unfounded since [1] it's working fine and [2] the original wiring splits the VSS signal into the speedometer circuit and the ECM anyway so it's always had the load of those two circuits. With this mod and and the Speedohealer installed, the load on the VSS is the Speedohealer and ECM instead of the Speedometer and ECM - that amounts to the same thing. We're all good!
End of thread · 32 posts recoveredWayback Machine snapshot 1 Nov 2020