Buzz Killl?

[Ben70_imp]

CAUTION! If you are considering this mod please hold off until I can determine if injector timing was also staggered. This was one of PowerDubs concerns along with ignition timing.
I have two indications that this may be the case. First, there is a rapid surge at idle after the engine is warm. I didn't notice this right away, partly because it doesn't do it cold and it is not huge, but it is consistent.
Second, there is a lean spot during acceleration when compared to the initial dyno run. Not toward the higher rpm.
I need to compare injector pulse widths, probably on one and four since they would be easiest to access.
Should have done that first. I suspect the Guhl flash may not be capable of altering individual pulse width, but I don't want to ask until I know that is what is happening.
So I need to locate a scope. A lab scope would work, or some automotive scopes.
I guess it was willful thinking that they wouldn't mess with pulse width, but why not?
On the other hand, it is only a 10 degree difference in 228 to 238. It doesn't seem like enough of a percentage to make a noticeable difference, less than 5%. Will have to check it out.

Ben

[PowerDubs_imp]

Glad to see someone else not afraid to rip into the engine.

Sorry to hear you are having issues.

My suggestion to anyone going beyond a slip on exhaust- is a Dynojet power commander and the auto tune box. Even if you get a guhl ecu.

Having the ecu be able to monitor a wideband O2 and constantly actually adjust to your specific bike, in every weather and altitude is the right way to go. It changes the fuel for all throttle positions, all rpm.


Sent from my iPhone using Tapatalk

[Ben70_imp]

Thanks for the tip, Josh. And for documenting your work, it is very helpful.
My idea was to find out the least I could do to get rid of the buzz, and just using the ex. cam on the intake side seemed do-able. The Guhl flash was incidental, I was wanting to do that anyway.
The idle issue is inconsistent, I hope to see whether or not fuel injector timing is even soon. I did hold it at 2500 rpm for a couple minutes and checked the head pipes with a pyrometer. It was within 5 degrees on 2,3, and 4, and between 5 and 10 degrees warmer on #1, so if it is lean it doesn't look bad enough to cause trouble and ran great on my ride today.
Will keep you posted on the cam situation

Ben

[PowerDubs_imp]

If you don't mind, I actually would like to see the dyno charts.

[Ben70_imp]

Here it is, PD...

Hope you can see it. The blue line is stock, with flat torque curve, strong, linear hp gain to what I assume is rpm cut out and mixture leaning a bit in midrange from stock and more, relatively at higher hp.
The other lines show leaner running across the board, torque diminishing with rpm and I asked him to cut it when it stopped making power, never did reach limiter. All done in 3rd gear.
Surprisingly, it feels good. Probably because in normal riding I don't get above 4 to 4500 rpm and passing power is good.
This was before the reflash, I will post new results with flash and a different cam profile soon. Also need to check my injector timing question. If it can't be brought closer to "normal" I will go back to the stock cam and live with the buzz, chalk it up to research. But it feels so nice I hope it can be made better. without a NASA style budget.

Ben

[max]

Ben on the subject of scopes you probably already know this but on the offchance here is a guy with a 4 chan picoscope specifically for automotive applications that demontrates in some detail what you may want to do.

https://www.youtube.com/watch?v=7Tf4a_ZeW_k

In addition to pulse with variation Honda may possibly alter the individual timing as well, i don't know this but without a degree scale this may not be obvious or easy to find, just an idea.

Do you happen to know if this timing " buzz " was inplemented from the getgo or was it introduced at some later point?
Interesting stuff you're doing.

[Ben70_imp]

Check out post #24. Looks like they wanted to give it some rumble, growl or whatever. It does sound pretty fierce when it gets that noise going on acceleration.
The lack of an urgent feeling at certain rpm's is hard to explain. When I mentioned "harmonic dissonance" in an earlier post, Dave asked for a technical mechanical explanation, which I don't have.
However, I Googled it, and found a lot of music references. Comparing chords and sound waves that intersect at even or uneven spots. Apparently it can be used as a musical device to provoke anticipation, or disquiet. I urge you to check it out, it kind of describes that feeling I get of "shift me , or make me go faster" that I feel in stock mode.
Interesting that that feeling is reduced with the higher gearing of a 19 tooth front sprocket and even more with the smaller rear sprocket, and may be why those with a six speed seem less likely to have a problem with it.
The term may have been used on me at an early age when violin lessons were inflicted upon me.

Ben

[PowerDubs_imp]

Thanks for the chart.

I am on my phone but will take a look later.

What else have you done besides the cams?

Any sort of exhaust or intake work?

Completely stock air & fueling?

02 sensor bypass or pair delete?


Sent from my iPhone using Tapatalk

[Ben70_imp]

Hi PD! PAIR plugged, O2 bypass, full Yosh exhaust. Running stock sprockets. The Yosh was on when I got it but PAIR was intact and it popped. Don't plan on other mods, but the fueling enhancements you suggest have me intrigued. Even with mismatched pulse widths a happy medium may be achievable. I hope to know more in the coming week.
Just checked ignition timing on 1&4 is the same. So that's confirmed anyway.

Ben

[PowerDubs_imp]

I'm interested in seeing what you continue to experience with further work.

Did you happen to ask for the actual run file from the dyno operator? ( .drf file). If not- they can email it to you as it is only kb.

I just bring a thumb drive with me whenever I dyno a car or bike.

I haven't touched my bike since I crashed, but given this stuck at home bs, I probably will drag it out when I run out of yard work and start replacing the scraped up bits. I already have the pieces.

I never got to dyno with the Guhls ecu, heck- only got to ride it for maybe 10 minutes. But I do want to redyno to see what's what.

For reference, if you haven't seen it- but you probably have, here is where I am at from last time- http://cb1100forum.com/forum/showthread....#pid215843


I would def richen up your fueling. If you decide to do the dynojet power commander and auto tune- you can also put a configurable dash on so you can keep an eye on it in real time- https://www.dynojet.com/power-commander-...0-display/