Another carb topic kinda question

[ALMOST]

If you guys remember I had an idle issue. Well I took The carbs off and gave them a cleaning. Idle problem fix. But now a new one. Right around 5000 rpm I get a back fire, just one little pop. I have not taken her out on the road yet, but the back fire is present when just reving the engine in the garage.

Is there some air getting in some were? Or just some thing else?

[ALMOST]

I noticed that while taking off and placing the carbs back on that the rubber boots, numbers 1, 2, 3 that connect the carbs to the intake were a little old looking. I did have a had time puting the carbs back on. So I'm thinking that I should recheck these boots. maybe there is some air getting in. I placed a diagram. I notice that I do not have the tube that comes from the back of the air filter box. I guess it is emission junk. Numbers 16 15 17

[reelrazor]

17 is a check valve-flows one way. That setup is a drain for the airbox...for either water or fuel condensation. That's why it is on the left rear corner of the airbox (low point when on sidestand).

[YAM93]

I guess i'm hallucinating, i thought it was the crankcase breather tube but maybe i'm missing that part also, or never noticed it.

I'll have to check it out.

I'd think backfiring would be caused by loose # 13 boots or whatever they're called.

[reelrazor]

Crankcase breather is large diameter hose going to the center of the back of the airbox(and above the 'floor' of the 'box).

[ragedigital]

I guess it is emission junk.

If you had a Cali bike, then that hose would be the least of your worries. Cali bikes have a vapor canister, reed valve system and the EXUP system. It wasn't a lot of weight, but it was a waste for sure...