Exhaust crackle and pop

[talkToTheHat]

So I had a Motad pipe in November. Did a carb sync when I came in after a ride as I was beginning to suspect it was a tiny bit out, and indeed I needed to move the sync screw a whole quarter turn, and then backed off the idle stop screw a little as she was idling a bit fast after the adjustment. This done I noted the vacuum gauges moving more in unison than previously, so new exhaust seems to have done a good job on equalising back pressure and resonance effects.

I had a good ride today, half a tank of back roads and working the bike pretty hard, quite a bit of WOT acceleration and letting the engine rev out. I noticed I'm getting quite a bit of crackle and pop from the exhaust on closing the throttle, both braking for a corner and engine braking down hill. Should I be worried or is this a sign everything is spot in. Sounds pretty awesome though. I had a little on the OEM pipes, but that was a sedate and muted pop pop pop amongst the wheezing.

I checked the plugs, not a plug chop or anything just post ride, and if I'm reading them correctly mixture is spot on with cocoa coloured combustion deposits. Running OEM pipes I had 33bhp exhaust washer restrictors and some dry carbon fouling. This is no long an issue.

Am running iridium version of stock plugs as they dramaticly improved my cold running when I had fouling issues. BPR7EIX

I think I'm just being paranoid, but thought I'd check.
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Bandit. does. everything.

[Matt B]

I wouldn't worry. It can be a sign of lean mixture but your plugs sound good.

Hard ride, hot and more free flowing exhaust, you will get some deceleration popping when you shut off.

Close the throttle and the mixture being pulled into the cylinder goes lean momentarily, this doesn't combust properly because it's weak and some passes through to the hot pipe. That's the theory anyway.
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stinkwheel: He had an animated .gif of a cat performing fellatio. It's not socially acceptable. It can have real life adverse effects on other people.

[Rogerborg]

^^^^
Technobabble.

It's testosterone dripping from your swollen sack onto the exhaust.
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Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[wots]

Couple of things in my experience.

1) A free flowing pipe is more prone to this, that may be all it is. Take the baffle out for serious pops (possible flame outs).
2) Any kind of leak in the exhaust system will make this worse, often much worse depending on the location and size of leak. A standard exhaust will pop in this scenario.
3) Iridium plugs are definitely hit and miss, I find them great for modern fuel injected bikes, but others don't like them. For instance my fireblade hates them. Last of the carb'd fireblades.
4) You've done the best you can to counter-act by sync'ing carbs, more than most.

Therefore, I wouldn't worry. But keep an eye on those Iridium plugs.
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Currently: Yamaha DT 125 LC2,Repsol Fireblade, and Bumblebee MSX 125

[Llama-Farmer]

Pretty normal and not much to worry about. Sounds cool too
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[UncleFester]

This is the reason i bought the exhaust i did after much youtube listening

Can't beat a fruity exhaust note with some pops and bangs and the odd bit of flame.

https://www.youtube.com/watch?v=97iJykS-HS0 I presume you sound something like this?
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2017 Z1000SX

[talkToTheHat]

Yes, that kind of pop and crackle sound, other sounds a but less manic as from a slower revving 72 degree vtwin. 8kRPM absolute tops. Is behaving around town as long as the red mist stays away.

Thanks for the advice and epic video link.
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Bandit. does. everything.

[Pete.]

Stock exhausts pop on the overrun too, you just don't hear it due to the noise deadening.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[talkToTheHat]

Stock exhaust was very very quiet, could hear the occasional pop. I've been a bit surprised at how aggressive sounding the motad has been since I've put a few miles on it. I'd gotten used to the sewing machine with a vacuum cleaner in the next room of stock and the idea of my wheezy inappropriate bike sounding like it is digesting the dead kittens I filled the petrol tank with is new and not keeping in concept with the bike.
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Bandit. does. everything.