Exhaust popping

[naughtyG]

So now I've been through my carbs Fuzzy idles perfectly, he got a good sync too yesterday, spark plugs are brand new and the COPs are fitted. I also put in 147.5 main jet on Sean's recommendation since I'm running the Dale Walker slip-ons at sea level, and the A/F screws are all at 2 1/2 turns out.
I set all my floats on the bench, haven't checked wet levels yet.

The bike runs beautifully, pulls hard all the way through the revs, but I'm getting a lot of popping in the exhausts. I know my '86 with the Jardine slip-ons (same design as the DW I have now) used to get a bit of popping on desceleration, and I put it down to the fact that those slip-ons are very open so one will hear a bit of pop, but this one is popping a bit on idle too, and I can hear it pop while cruising at low revs. The only time it doesn't pop is on acceleration. I remember people saying this would usually be due to air leaks in the exhaust, or a lean condition. I haven't checked the down pipes exits yet, but just wondered if anyone had any suggestion?

 

[one2dmax]

Might want to turn out the a/f mix screws a little and see if that helps.

 

[mr.maxx]

my supertrapps were popping like mad.....i repacked em and they are much better now.

 

[wishbone]

Mine was popping like crazy last week, yep leaky exhaust gasket. and loose pipe to.

 

[bazwell]

Congratulations on getting the bike mate! WOO HOOOO!

 

[redneksoldier]

As Sean recommended, try turning the A/F mixture screws out a tad. Popping in the exhaust on decel is usually from a slightly lean condition. Also check for vacuum leaks. As I discovered on my '93, if the intake boots and sync vacuum caps get old and hardened they WILL leak around the ends even if the clamps are tight and there are no cracks in the boots and caps themselves.

 

[Diablotin]

Yep exhaust or airbox leaks were the reasons why it was popping for me... After playing with the AF it reduced the effect but it was still there.

Sent from my GT-I9100 using Tapatalk 2

 

[naughtyG]

Yea I think I do need the vacuum nipples as they're pretty hardened and one is cracked. Anyone got any of those lying around?

Also gonna check the exhausts seals, and turn the A/F out to 2 3/4 turns to see if it helps.

Baz, we going riding soon?

 

[Rusty McNeil]

Those rubber vacuum cap are usually available at auto parts stores off the shelf in a multi pack for a few dollars.
The ones I bought cracked and split after a few years so there prolly not as good as the stockers. But they are cheap to replace.