To rich or to leans?

[Higgins13]

I recently completed the mods below. Seems to run well however I notice it takes longer to warm up then before. I'm not certain but if I drive it hard then let off the throttle there may be some popping crackling from the exhaust. I read that this may just be because it is a high flowing exhaust. Weather also also been cold and may be effecting things. What are your thought?

[BockinBboy]

Sounds slightly lean.  Colder air makes a bike leaner because it is more dense.  Leaner bike=longer warm up time. Check your plugs for more direction. 

What is your jet sizing?

- Bboy

[Higgins13]

Don't know the numbers but it is what the dynojet kit made for this bike said to do.

[Funderb]

if you have a lunch box, and a pipe, you need to be in stage 3 territory, not stage one. you are likely well lean of peak.

[RossLH]

What kind of story do the plugs tell?

[802 305]

According to Mikuni, a well-tuned high performance engine is supposed to pop on decel. The reason for this is the super lean condition created when downshifting hard or letting off the throttle restricts the mixture being taken in to the pilot system at the higher engine speed when it would usually pull through the main. Right? Definitely take a look at the plugs though. If it is really lean, the idle will be hanging typically at stops and be very erratic, or at least those were my symptoms. One indication of a super lean condition would be popping on acceleration and that would really need to be fixed.
Almex

[Higgins13]

No popping on acceleration, idle is low at first and it take longer to warn up. I'm only hoping its due to cold weather, after a longer then normal SUMMER ride it idles just fine...

I would have to say the popping is def not a backfire sound.

[Funderb]

might as well turn your idle mix screws 1/4-1/2 turn richer, it will help the popping for sure.

[Higgins13]

Regarding longer warm up times. Can this be caused by new spark plugs or running to lean?

[BockinBboy]

If anything, new spark plugs would shorten warm-up given that your old ones were dirty or needed replaced.  A leaner bike will take 'longer' to warm-up... than say a bike running at ideal mixture or little rich.

- Bboy

[Higgins13]

They are iridium ones from china. Wondering if bike ran better with oem plugs