So I'm Chris ,You can send it back for a full refund as i said in the email this morning .
I changed the pipe back about 18mths-2yrs ,The reason is function .Since there is Devillic (china) or hindle are around nowadays I changed up the 4-1 to include a stepped header so this is the best performing pipe for a 500-550.The stepped header is flared and then seam welded (most exhaust companys just slide one into the other ) .So I have to bend two sets of headers to make one .
The collector is larger also and this is due to most guys have pod filters or a set of Cr's so its all about getting (o2) Air in ,Air used and exhaust out .
Yoshimura back in the day started stepped headers only on there factory bikes,Its all about having a smaller dia header pipe for torque (slight back pressure , helps encourage scavenging ) and the stepped (larger dia) for flow once your on the throttle/gas .The larger collector helps merge those gasses and sends them down the pipe .Thats the basic version .
I still make these maybe 5-10 a year,I still use American stainless and components so the cost to make these now is well over what I sell them for .I really don't have time nowadays as i m building my own production bike for the past 8mths & customer bikes but I still like building the odd pipe for #$%* and giggles.
I will be making a new cb550/750 pipe in the next 2 mths ,last version ever and will be a true merge collector
But please if its not your thing just send it back ...
