Pffft noise...

[NE_Valk]

Noticed the other day that I have a pfft pfft noise coming from the right side when I get on the throttle uphill or "rod" it a little.  Thought it was a possible exhaust leak but then noticed it makes the same sound when the choke is full on.  Sprayed around a little to see if I had an obvious vacuum leak but to no avail.  Did notice that the clamps on the airbox to carb boots were completely loose.  Currently have the tank and airbox off for desmog and new petcock.  Anyone else experience this noise with the choke on and have suggestions?  Perhaps just needs clamps tightened back up or had a small vacuum hose leak?  Bike is a 00 Interstate, one owner (I'm #2).  Got it about a month ago, first Valk.  He had the carbs totally rebuilt 2 yrs ago (receipts for like $2200) but only driven like 500 miles since.  Not too impressed with the workmanship (exhibit A is the loose clamps but there's several other things).  Any suggestions I'd appreciate it.

[Hook#3287]

Carb totally rebuilt is subjective.  Could mean many degrees of what was actually done.

I'd start with the air box and work my way down to the exhaust headers checking every hose, clamp, cap, nut, bolt and screw.

Be careful on the exhaust header nuts cause those studs have known to be fragile.

If she's been desmogged, you need to see if it was done correctly and any caps or plugs are good.

Good luck.

[9Ball]

Noticed the other day that I have a pfft pfft noise coming from the right side when I get on the throttle uphill or "rod" it a little.  Thought it was a possible exhaust leak but then noticed it makes the same sound when the choke is full on.  Sprayed around a little to see if I had an obvious vacuum leak but to no avail.  Did notice that the clamps on the airbox to carb boots were completely loose.  Currently have the tank and airbox off for desmog and new petcock.  Anyone else experience this noise with the choke on and have suggestions?  Perhaps just needs clamps tightened back up or had a small vacuum hose leak?  Bike is a 00 Interstate, one owner (I'm #2).  Got it about a month ago, first Valk.  He had the carbs totally rebuilt 2 yrs ago (receipts for like $2200) but only driven like 500 miles since.  Not too impressed with the workmanship (exhibit A is the loose clamps but there's several other things).  Any suggestions I'd appreciate it.

The loose clamps are not really much of an issue.  They always seem to need some snugging up once in a while.

Totally rebuilt is very subjective.  If the bike seems to idle and accelerate okay then other than leaks you should be good for awhile.

Check the vacuum caps on the intake runners for good condition.  Tightening things up is a good start too.  Are your intake orings in good condition?  Any brown stains near the intakes on the heads?

Good luck...

[Jim in Idaho]

Make sure all intake runners are INTIMATELY mated with the air box connection as well as the valve intakes.  I recently had problem with all cylinders on the left side of the motor running rich and found that the interface between the intake runners (which I had recently swapped out) and the carbs were not fully seated on that side on each carb.  Lost a lot of zip even though the bike ran "fine" overall.

All the punch returned to normal after reseating the intake runners and the bike is no longer running rich.

Jim in Idaho

[Jess from VA]

Beans and onions?               (apologies in advance)

[NE_Valk]

Thanks fellas. I'll check all these things out and see where I'm at.