Almo Posted December 4, 2019 Share Posted December 4, 2019 (edited) Hi guys I'm a new member from New Zealand here. I've just signed up to ask a question on behalf of a buddy of mine who doesn't like using computers Lol. He has a near new '19 model and he's fitted his full system carbon Akrapovic off his old '15 model MT-07. Now the new bike is popping quite badly on decel but his old bike never did this. Is there a difference between the two in the fuel maps or such like? To pass the Euro 5 regs perhaps? Runs leaner? We know it could be tuned out with an ECU flash job but he'd like to avoid that route.. Any thoughts? Edited December 4, 2019 by Almo 1 Link to comment Share on other sites More sharing options...
geophb Posted December 4, 2019 Share Posted December 4, 2019 Its in the tuning. Only a flash will cure it. If you listen close the stock exhaust even does it, but very quiet. Link to comment Share on other sites More sharing options...
Beemer Posted December 4, 2019 Share Posted December 4, 2019 there is a slightly cheaper route to help diminish the decel popping, I have one and that's with a Dobeck EJK but you won't get all the added features that some flash jobs offer, say like the one from 2 Wheel Dynoworks, a very popular and respected vendor on this forum. If I had it to do all over again I would spend a little more and go with the 2WDW flash. GL! ... to your friend of course. Beemer Link to comment Share on other sites More sharing options...
Almo Posted December 4, 2019 Author Share Posted December 4, 2019 Thanks guys. There is a guy in the South island where we live who does ECU flashing using the Woolich software. I got him to do my Ninja 400 last year with good results. Probably the best option for him. I'll sow the seed LOl. 1 Link to comment Share on other sites More sharing options...
klx678 Posted December 4, 2019 Share Posted December 4, 2019 FWIW decel popping isn't really horribly damaging. Mikuni tells about it in their carburetor FAQ. Closed throttle revs up a bit causes a lean condition that will cause unburned charge in the exhaust until enough collects and it fires - the exhaust crackle you hear. Stock chambered mufflers hide the crackle, straight exhausts will both increase and accentuate the crackle. Either way the fix, if it bothers someone is to enrichen the mix at low rpm. In a carbed bike the pilot jet size is increased, but Mikuni points out it is actually detuning that range going overly rich for actual run conditions versus deceleration. Funny thing is in my research on the subject it seems Corvette owners and some other car owners want to know how to increase the exhaust crackle, they like it. Much like the crackle of racers on deceleration coming into corners. They want it, motorcyclists don't. Go figure. For me, I don't care. My KLX650 had crackle, all I had to do to stop it was hold the throttle on slightly and it was gone. Link to comment Share on other sites More sharing options...
kylerhsm Posted December 4, 2019 Share Posted December 4, 2019 My Akra Carbon gave out the occasional "bang" on decel which I found pretty annoying when I first got the bike. This is just a result of the exhaust being a little too free flowing for the stock tune. I bought one of these (plenty on eBay if you search universal 51mm db killer) which slots between the muffler and the header with no modifications needed. Literally takes 5 minutes to install. It got rid of loud bangs and now I just have the awesome rumbling/crackling without the random explosions. I use this in conjunction with the standard db killer. 1 Link to comment Share on other sites More sharing options...
klx678 Posted December 5, 2019 Share Posted December 5, 2019 See! Another fan of decel crackle. Link to comment Share on other sites More sharing options...
geophb Posted December 5, 2019 Share Posted December 5, 2019 15 hours ago, klx678 said: FWIW decel popping isn't really horribly damaging. Mikuni tells about it in their carburetor FAQ. Closed throttle revs up a bit causes a lean condition that will cause unburned charge in the exhaust until enough collects and it fires - the exhaust crackle you hear. Stock chambered mufflers hide the crackle, straight exhausts will both increase and accentuate the crackle. Either way the fix, if it bothers someone is to enrichen the mix at low rpm. In a carbed bike the pilot jet size is increased, but Mikuni points out it is actually detuning that range going overly rich for actual run conditions versus deceleration. Funny thing is in my research on the subject it seems Corvette owners and some other car owners want to know how to increase the exhaust crackle, they like it. Much like the crackle of racers on deceleration coming into corners. They want it, motorcyclists don't. Go figure. For me, I don't care. My KLX650 had crackle, all I had to do to stop it was hold the throttle on slightly and it was gone. The glory of efi. Can remove decel popping without affecting idle!! My bike didn't crackle (which wouldnt have bothered me). Mine would straight up back fire multiple times! It was louder than the pipe at full throttle. Link to comment Share on other sites More sharing options...
Beemer Posted December 5, 2019 Share Posted December 5, 2019 I get the occasional crackle .... crackling be goooood! Loud bangs suck. 1 Beemer Link to comment Share on other sites More sharing options...
klx678 Posted December 5, 2019 Share Posted December 5, 2019 Yep, crackle is one thing big bangs another. The former is no big deal the latter means there's a problem somewhere. Link to comment Share on other sites More sharing options...
Socalmt Posted December 12, 2019 Share Posted December 12, 2019 The crackling on decel sounds cool just sayin’ Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now