OK Jan... sorry for the late response. I been consoling the SG. She took it kinda hard when I told her she had slow throttle response.
Anyway... just like I'd never heard of burnt valves from not enough advance being a thing... too much advance (within reason) causing poor throttle response is another "thing" I'd never heard of. So I googled it. I'll add an interesting video at the end, but here's the gist of what this guy found out with his 70's era hot rod.... advancing the timing at idle actually improved throttle response. He started at 8° and pushed it up from there. I had to re-watch the video to make sure I didn't miss something, but all else being equal, this guys best throttle response was at about 32-33°. That's not a typo... thirty two to thirty three degrees of advance was where his quickest throttle response off idle was.
Does that mean my 18-19° is OK? Of course not. But it is a good indicator that my 3-4° more than stock is
most likely not hurting anything. And since I'm now running the highest octane fuel I can get, having it advanced most likely
is helping throttle response.
Now, I've responded to this because others are, or are considering using this box. Since
@Team Junk hasn't been on the forum since Sept, and since I jumped into this with Jacks encouragement, I feel a bit of an obligation to keep the bus steering between the lines. On that note, this is my last rabbit hole. If anyone puts a fresh query up and I don't respond... well, there's your answer.
Btw, I hope Jack's (teamjunk) OK. Not hearing from someone gets kinda worrisome in these trying times.
Yes Sir and thank you for the answer Sorry if it appears overly Critical
But it is really Combustion engine Physical laws And not so much personal view or opinions
Please look at the curves
https://en.wikipedia.org/wiki/Ignition_timing
Ignition advance is there for giving the mixture time to burn and create the driving force for the piston
If we accept a little later advance at full advance so we not risk pinging
Why cant we accept the same at the retarded position ( or that there is an optimum )
Assume a too early ignition -- to much advance curve b
Clockwise rotation seen from right side.
To high pressure at the wrong time
The piston is on it s way up and the ignition lights the mixture the pressure builds and the piston is till moving upwards.
Compressing .. then one gets a rotational preventing force on the piston --less Effect .
If it is to late say exactly at top dead center. curve d
Then the piston is already on the way down and combustion chamber pressure is less at the wrong time
..even with fully burnt mixture
There exist a optimum advance curve c
If the ignition spark occurs at a position that is too advanced relative to piston position, the rapidly expanding air-fuel mixture can actually push against the piston still moving up, causing knocking (pinking or pinging) and possible engine damage, this usually occurs at low RPM and is known as pre-ignition or in severe cases detonation. If the spark occurs too retarded relative to the piston position, maximum cylinder pressure will occur after the piston is already traveling too far down the cylinder. This results in lost power, overheating tendencies, high emissions, and unburned fuel.
Yamaha has designed the engine with at the retarded end 13 -15 degrees BTDC
And it is a Machine sold with that in for about 15 years. If it was off in some sense with over 250 000 machines sold they would have changed it.
For me that is a indication that it should be around there.
DEVELOPMENT
There can be changes needed mostly because perhaps Fuels and other things Coils spark etc. .Other advance settings can be better .. What do I know.
I dont know how much testing has been done to reach the 18-19 and the Gonzo but it can by no means be 250 000 bikes under 15 years
Please understand the view that the Mentioned Physics and 250 000 bikes give an indication that less advance at idle can be better.
I do believe most enthusiast today at least in their setting would like to have the possibility to test factory specs.
At the lower end.
If no adjustment possibilities exists there is the risk that holes are drilled in rotors for magnets 5 - 6 degrees wrong
Please bare with us / me .. We / I don't know all and has not test driven the bike.
What we do know is the factory setting and the big number driven with that spec
And has some knowledge of the combustion process
As well as of the bike for 35 years
This can be better ....But we don't know that .. And it will be seen after more people install the Gonzo box.
People are gonna try moving the advance a little as they do with other ignitions.
Uploading videos
And every man makes his own decisions and chose how his bike shall run. The curves are there.
.