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No Surge + Autolite 3923 plugs + wow!
- Thread starter mgordon
- Start date
MotorradMike
Lucky
That is very encouraging. Is that change just from the plugs? I may give that a shot. I am not wrench savy, but I can do plugs..I think.
Before you start, clean all the little stones out of the spark plug channel. Make sure the socket fits all the way down to the bottom.
Some folks have had trouble when the socket gets jammed.
MotorradMike
Lucky
So now you're a believer.
Please provide an explanation if you can.
To me, another believer, this fix is preposterous.
mgordon
New member
All I can tell you is that I had noticeable surge, did obsessive TB sync, etc. Had very strong surging and fuel cut-off at low RPM. Changed plugs, rode the bike...and I'm a believer.
Go figure, but remember Rob Lentini was the first one apparently to widely report the better performance. Fatter spark is my guess.
pglaves
#13338
Unfortunately, no.
breyfogle
New member
My 1100 never did surge, but when I bought it, it did stumble once and awhile at idle. It never actually stalled but it sure did not idle with confidence. Changing the stock Bosch plugs for 3923's completely cured the idle stumble. My 2 cent opinion is that the traditional axial-fire Autolites (and probably any single electrode plug) will ignite an ultra lean mixture better than radial-file multi electrode plugs like the Bosch.
I agree with the "unfortunately" bit! I have raised this question before as to why the BoD's/editor don't make this tech stuff available in a reachable form. I have seen the answer but still have to say that given the level of tech interest in the membership, it is a shame we cannot go after this information/knowledge. Rant over...
Mike_Philippens
Certifiable User
What was the condition/age of the old plug when you changed it? New?
I had my bike serviced and when it came back it was fine, but I wanted to have the spark plugs everybody was talking about: the iridium. I swapped them against the brandspankingnew originals that the mechanic put in and went for a ride...absolutely no difference...
So I wonder: is it not so that when you exchange old plugs for new ones, there will be an improvement, regardless if it's the wonderplug or just the original?
I had my bike serviced and when it came back it was fine, but I wanted to have the spark plugs everybody was talking about: the iridium. I swapped them against the brandspankingnew originals that the mechanic put in and went for a ride...absolutely no difference...
So I wonder: is it not so that when you exchange old plugs for new ones, there will be an improvement, regardless if it's the wonderplug or just the original?
breyfogle
New member
Well, the thinking is like this (and ICBW!!): The intake charge drawn into the cylinder is very turbulent. Not all areas have the correct air to fuel ratio to ignite easily. In modern ultra lean burn engines, some of these areas are too lean to ignite while other areas are rich enough to ignite just fine. As the piston rises on the compression stroke, these areas of charge swirl around rather randomly. If the plug fires just when a lean area passes thru the spark gap a miss-fire occurs. With a traditional axial fire single electrode plug, the spark gap is very exposed to swirling flow from every direction except the small angle blocked by the side electrode. With multi electrode radial fire plugs, the spark gaps are tucked uo against the plug body and seem to be shielded from almost every direction. This increased shielding might decrease the chances any of the spark gaps "seeing" a combustable air to fuel ratio when the plug fires. Note also, just because a plug has multiple electrodes doesn't mean more than one spark is produced. On each cycle, only the one spark gap that sees the minimum resistance fires. The others do nothing except block the flow to the spark gap that does fire.
i have you seen the price of membership
lately? For the amount that we pay, they had better offer something that not anyone else can get.
I seriously considered not renewing my membership this year when i found out how much my 5 year membership was.
Rant off....
lately? For the amount that we pay, they had better offer something that not anyone else can get.
I seriously considered not renewing my membership this year when i found out how much my 5 year membership was.
Rant off....
Thanks for the follow-up. I get the physics involved, but I just don't know if it really matters. Of course, way,way back in college, a physics professor told me there are some things you just have to take on faith. I just shook my head and thanked him.Well, the thinking is like this (and ICBW!!): The intake charge drawn into the cylinder is very turbulent. Not all areas have the correct air to fuel ratio to ignite easily. In modern ultra lean burn engines, some of these areas are too lean to ignite while other areas are rich enough to ignite just fine. As the piston rises on the compression stroke, these areas of charge swirl around rather randomly. If the plug fires just when a lean area passes thru the spark gap a miss-fire occurs. With a traditional axial fire single electrode plug, the spark gap is very exposed to swirling flow from every direction except the small angle blocked by the side electrode. With multi electrode radial fire plugs, the spark gaps are tucked uo against the plug body and seem to be shielded from almost every direction. This increased shielding might decrease the chances any of the spark gaps "seeing" a combustable air to fuel ratio when the plug fires. Note also, just because a plug has multiple electrodes doesn't mean more than one spark is produced. On each cycle, only the one spark gap that sees the minimum resistance fires. The others do nothing except block the flow to the spark gap that does fire.
scootrp125x
They call me Gort
benchwrenching articles
I happen to have a copy of Paul's Benchwrenching articles from October and November 2008. I try to save as many of Paul's excellent articles as I can so I can refer to them in the future. I have access to a scanner at work that can email copies as a pdf file.
If anyone would like a copy please pm me with your email address and if I can get the articles scanned into email I will send you a copy. Please give me a few days since I am off until wednesday. Please send your snail mail address too and if the scanning doesn't work I will try to mail a few copies of the articles to you.
Gort
I happen to have a copy of Paul's Benchwrenching articles from October and November 2008. I try to save as many of Paul's excellent articles as I can so I can refer to them in the future. I have access to a scanner at work that can email copies as a pdf file.
If anyone would like a copy please pm me with your email address and if I can get the articles scanned into email I will send you a copy. Please give me a few days since I am off until wednesday. Please send your snail mail address too and if the scanning doesn't work I will try to mail a few copies of the articles to you.
Gort
grafikfeat
New member
scootrp125x
They call me Gort
I can't imagine that it is illegal to distribute free copies but I will check with the home office.
