I just completed a sportster muffler install, I haven't rejetted the carb yet, but did adjust the mixture and idle settings prior to the new muffler install and really cut down on the backfire. I do have the jet kit, but just got tired today and didn't get around to pulling the carb.

Of course I couldn't wait and had to take it for a ride regardless - even without a rejet I was really pleased.

It had a lot more pickup and a lot more midrange and top end - took it out for about 45 minutes and upwards to 60mph - I had a few little burps on decel but that was ok - otherwise it seemed to run great. When I got home I cut the engine and expected a bang or at least a poof - but nothin... Everything seems great.

So I need opinions - should I still rejet the carb or run it as is since it seems to be running pretty nice right now.

I have my mixture screw at 2.5 turns out and the idle adjusted to a pretty nice gait. (when I got it it was running real lean and had a heck of a bang when I turned it off)

definitely re-jet. I had mine (sporty pipe) on for about a week and the mixture screw out about 2.5 also. The thing runs lean as it is and the sporty pipe lets air flow even more, hence, even more lean. If anything, remove the spacer and don't go much over 3/4 throttle until you get the jets. You'll need them for WOT. Needless to say, I have the stock "Mr. Economical" pipe on now, which sounds dumb, but won't burn me exhaust valves. Check out the thread on how to Re-Jet and you will learn a lot!
Take care and ride safe
RSD

'bout how long a job was it from start to finish ? Just curious Im waiting on my kit from Lancer now to rejet. Have had my Dyna muffler about a week now with pretty much the same results you mentioned. Tweaked the mix screw as much as possible before rejetting and definitely better, just gotta get the new jets installed. Which size jets did you install BTW ? Thanks and ride safe....

funny thing was, when i got the muffler on and took it for a ride, prior to rejetting- it ran great! However the next morning heading to work it was bucking and all like it was out of gas, that's what made we do the rejet.

And I forgot to mention, I went with the 152 jet - figured I would start in the middle. I haven't gauged how it has affected mpg yet.

I just put a Dyna muffler on my bike Tuesday and I'm loving it -- not too noisy, looks good, no apparent loss of power compared to the old Supertrapp.  Bike runs OK now, which is to say that it was spotty before and still needs a lot of choke when cold and stumbles occasionally in mid-range. I have Lancer's kit and will do this soon, but have a question:  I think I recall seeing somewhere that there was a consensus as to how to re-jet for the Dyna muffler.  I can't find this -- can anyone direct me to that thread??   Thanks.

shadowman wrote on 08/07/08 at 09:03:59:


Links to carb tuning here (tech section): http://suzukisavage.com/cgi-bin/YaBB.pl?num=1181745927

Did you rejet for the Supertrapp?  I'm thinking the Dyna muffler is more restrictive than the Supertrapp.  Check your plug where you are now to see if it's running lean or rich.  If it's stumbling, I'm thinking you may be rich.  If so, add a pod filter, or the cheap foam filter and that may fix it without a rejet.  If your lean, take it up one step at a time till your plugs look good and it's smooth through the throttle range.

For reference, I'm running 152/55 with Screaming Eagle Sportster Turnout Pipe and a Emco pod filter.  It's very unrestricted.