'05 Silverado, 24k miles.
PO had replaced plugs prior to my purchasing. Bike sat for 4 years. PO ran BG 44k through it.
Has V&H ProPipe. When I purchased it had no baffle. Bike ran great, except it being VERY loud.
Bike has a lot of decel popping
Got a new baffle and it sounds great! But still have the popping.
Bike also has a K&N in the stock air box.
No other mods that I am aware of.
The fuel pump is still in use. I plan to go pumpless
Removed AIS and still have a lot of decel popping.
From the research and reading that I have done, it sounds like that the bike is running lean.
Pulled the plugs this morning and they are showing rich. A lot of black carbon.

I can not see any obvious cracks on the intake.
Can you see cracks while it is still mounted?

I would like to do the poorman's bak.
I know that after doing that, I will need to re-jet, but with it running rich now, not sure which direction to go.

Any help from the masters of carbs, would be great.

Rg

You need to open up your carb and see what jets you have. Regarding your popping, have you checked torque on your exhaust pipe flanges at the head, or checked them to see if the backing plates are bent? Under torque leaks. Not re checking them after the first few heat cycles after install leaks. Being over torqued causes the gasket to distort and leak.

Here is what I found.

Carb numbers: 5VN1 00 L474

Slide needle, 4th clip, brand? Bottom of needle is blunt
Main jet: AB 142.5
Pilot: FJ 37.5

No obvious cracks in the manifold.

Exhaust flanges are straight.
1 bolt was loose on the rear
1 was slightly loose on the front
Re-torqued to 15 ft lbs

I am going to resurface the intake flanges and replace the or rings.
Will use a sealant upon re-install

Suggestions?

Rg

Do one thing at a time or you'll never know which thing fixed the problem.

Also, I have ported the intake

rginsbtx wrote:
Here is what I found.

Carb numbers: 5VN1 00 L474

Slide needle, 4th clip, brand? Bottom of needle is blunt
Main jet: AB 142.5
Pilot: FJ 37.5

No obvious cracks in the manifold.

Exhaust flanges are straight.
1 bolt was loose on the rear
1 was slightly loose on the front
Re-torqued to 15 ft lbs

I am going to resurface the intake flanges and replace the or rings.
Will use a sealant upon re-install

Suggestions?

Rg

The 142.5 don't sound correct. Are you sure it doesn't say 182.5? If it truly says 142.5 throw it in the garbage can, Throw it in the can even if it say 182.5 and buy a 172.5 Mikuni along with a 37.5 mikuni pilot jet. Don't assume that the 37.5 pilot jet that you have is the same as a Mikuni. Set the PMS at 2 1/2 turns out
Also check the exhaust joint mid way in the pipe. The heat shield on those pipes usually turns a little yellow mid way due to a leak at that joint. That can also cause a decel popping. Porting the manifold won't change the jetting it will only make it run better. If you use a sealant with the intake manifold only use a Hylomar
non hardening fuel resistant type sealant not RTV silicone.

Also, I have ported the intake

rginsbtx wrote:
Also, I have ported the intake

Thats fine it will run a little better

rginsbtx
Did you solve this problem with the popping?
My bike just started doing this decal popping about 2 weeks ago, it has been working fine since I bought it over a year ago. It will also stall on occasion when taking off (about once a day), it seems like it has an air bubble in the system that pops when I take off then stalls the engine.
Any information will help.
thanks
steve

saszeus wrote:
rginsbtx
Did you solve this problem with the popping?
My bike just started doing this decal popping about 2 weeks ago, it has been working fine since I bought it over a year ago. It will also stall on occasion when taking off (about once a day), it seems like it has an air bubble in the system that pops when I take off then stalls the engine.
Any information will help.
thanks
steve

Make sure your idle is set to around 900rpms, and it may be you've developed a vacuum leak. Either the Coasting Enricher cover, the intake manifold, or the AIS system if it's still on the bike, are all prime suspects for an air leak.
If you set the idle correctly, and pull the Enricher out a little bit when the bike is warm and your riding and the stumble and popping disappear, then you can be pretty sure it is an air leak.