New into Harleys and recently bought a new Fatboy and had S&S slash cut pipes fitted to the bike. Everything else is standard. Bike sounds good but when I back of there is an exhaust popping noise. Thi swoukd have to be detrimental to the motor. THe Harley shop I bought from said the pipes should be OK with out any other changes. Keen to get some other opinions on this

 

Iggy

 

Or you could go Screaming Eagle Tuner, Thundermax is what I use had a good run with this device, easy to install. Lots of usefull stuff on this forum relating to EFI stuff.

 

Go to the EFI posts and check that out may help you with some decisions on what to do regarding EFI updates

It's running a tad lean. As a quick and cheap fix, plug in an aftermarket fuel enhancer like a PC V or VH fuel shot. There are a few mentioned on the site. When and if you trick it up go for the downloadable units like a TTS type item.

how bad is it? even tuned it will prob still do it a bit, just sayin....

I would buy a SE super race tuner,The orange tuner about $750, then get the shop to do a smart tune on it, problem solved..

sounds normal,dont forget the exhaust is traveling out fast then when you close the throttle nothing a vacuum forms sucking the air back in the pipe makeing that pop sound.The smart tune is done out on the road while the mechanic is riding the bike.

Thanks for the feedback.  Agree probably should have bought an EVO, maybe next time. The exhaust is there only when backing off, and my main concern is damage this may cause, as I assume it is happening in the head of the motor.

I will most like go to a SERT and air cleaner down the track as I live in a Regional city and not too many options locally other than the HD dealer.

Pizzlin, your advice is logical, but is a heat proof silicon required??

Iggy

 

 

 

just a tip. If using silicon before the 02 sensors (If you have them), make sure it is sensor safe silicon.

change your name, no more pop

my moneys on the tune.

I believe that pipes alone do not warrant an 'out of the box' ECM download which you can have the dealers do for a price. If you changed the air filter as well then maybe.

My suggestion ss you may have an intake leak, especially if it pops around 2500 rpm give or take a couple of hundred rpm.

If it decel pops at high rpm for a long period during decel I would suggest a lean condition. If it's a low RPM decel pop I would pull the pipes, loosen the headers at the front & rear manifolds and starting at the rear muffler mounts recheck the alignment and re-tension all connections working up to the exhaust manifold.

I don't think I would use any sealant, rather use some hi temp neversieze and make sure you slide the slip-on's over the header as far as you can within the slack provided in the mounts. Clean the header ends really well first.

Note: Always start with the cheapest and easiest when troubleshooting-- you just might be surprised at what you find. Just my two cents but worth a try for small expenditure (can of neversieze if you don't have any).

I have checked the rev range where the exhaust pop is the worst and 1800 - 2000 is worst, and 2000 to 2200 is not quite as bad. The rest of the rave range is all good. Taking the bike in for it's first service tomorrow so will disucss the exhaust pop with the mechanic.

Thansk to all for their opinions and advice.

Iggy 

Had the bike serviced today, and they found no leaks in the intake and exhaust system. HD Mechanic said only real option to sort is a SERT or similar. Also said the exhaust pop will not damange motor.

 

Iggy

Finally got around to adding a SE Super Tuner to the Fat Boy. The exhaust pop is nearly gone, and definitely an improvement. Added a K and N Filter as well now so basically a stage 1 set up now. Cost of SE Super Tuner, Stage 1 EFI kit and K & N filter, fitted and bike tuned all installed by a HD dealer - $1100 to a stage 1 level. Pipes were already fitted from new. Sounds a bit louder now as well.

Thanks to all for the feedback

 

Iggy Pop without the Pop