gusimus
CB750 New member
Hey Guys, I guess I am the newest member of this group at this exact moment, so wanted to say hello and then get down to business.
First let me make sure that I am in fact posting in accordance to the forums rules...let me know if I need to read anything or do anything etc...
Ok, so now for the opinions thing,...I have been trying out some different spark plugs on my 79' and am getting different results...the question I have is this...
i was using NGK D8EAs as per the manual and then switched out to NGK DREIX8 iridiums, didn't like them so went back to the D8EAs...I found that everything works just as it should with the D8EAs but there is a bit of a lack of oomph as compared to the iridiums (the iridiums caused other issues that I didn't like) i then tried some other plugs for shits and giggles called E3 diamond sparks,,,
The E3s allow for better cold starts a bit more throttle response and a really smooth idle, like really smooth...the issue i am having is this...when I get into the higher rpm range (around 7000 and up) I am getting some backfiring and what feels like a rev limiter kicking in...
This is not happening with the D8EAs....only with the E3s
I am running 900 cams, 900 spark advancer, procom igniters, dyna 3 ohm coils with the bypass relay mod, brand new battery, valves lapped a couple months ago, compression a cool 150 across the board, carbs rebuilt last year and cleaned really thoroughly 3 weeks ago, charging system working fine (all connections cleaned and checked)
I've got stock airbox on the CVs, no leaks anywhere that I can find, and stock main and idle jets (68 and 102)
Is it at all possible that the E3 plugs are needing more gas in the higher throttle position? Would this popping be a lean condition aused by the main jet being a little too small? I was thinking about bumping it up to a 105 to see if that would make a difference.
i can't for the life of me figure out why this is happening, any help would be much appreciated.
Also, the bike seems to be much quieter with the E3 plugs in, like super smooth sounding....
Anyways, thanks in advance for reading...Gus
First let me make sure that I am in fact posting in accordance to the forums rules...let me know if I need to read anything or do anything etc...
Ok, so now for the opinions thing,...I have been trying out some different spark plugs on my 79' and am getting different results...the question I have is this...
i was using NGK D8EAs as per the manual and then switched out to NGK DREIX8 iridiums, didn't like them so went back to the D8EAs...I found that everything works just as it should with the D8EAs but there is a bit of a lack of oomph as compared to the iridiums (the iridiums caused other issues that I didn't like) i then tried some other plugs for shits and giggles called E3 diamond sparks,,,
The E3s allow for better cold starts a bit more throttle response and a really smooth idle, like really smooth...the issue i am having is this...when I get into the higher rpm range (around 7000 and up) I am getting some backfiring and what feels like a rev limiter kicking in...
This is not happening with the D8EAs....only with the E3s
I am running 900 cams, 900 spark advancer, procom igniters, dyna 3 ohm coils with the bypass relay mod, brand new battery, valves lapped a couple months ago, compression a cool 150 across the board, carbs rebuilt last year and cleaned really thoroughly 3 weeks ago, charging system working fine (all connections cleaned and checked)
I've got stock airbox on the CVs, no leaks anywhere that I can find, and stock main and idle jets (68 and 102)
Is it at all possible that the E3 plugs are needing more gas in the higher throttle position? Would this popping be a lean condition aused by the main jet being a little too small? I was thinking about bumping it up to a 105 to see if that would make a difference.
i can't for the life of me figure out why this is happening, any help would be much appreciated.
Also, the bike seems to be much quieter with the E3 plugs in, like super smooth sounding....
Anyways, thanks in advance for reading...Gus