"Pssss" --- sound from carb area when giving throttle.

[EvenmoreXS]

Opinions please. Im leaning towards the throttle shaft seals.

Bike cranks and idles ok. Occasional pop/suck from carb and bike will cut out. I think i have an intake leak.

When i bump the throttle, I get a "Pssss" sound from somewhere near the carbs, havnt been able to locate the exact spot. If I hold the throttle its still there but its covered by the Revving engine. But the initial throttle bump results in a Pssss sound. Its audible. Dont have to listen too hard to hear it. Not a phantom sound. Its consistant and repeatable.

New boots and gaskets 6 months ago. New blind plugs on the stems. Tightened the boots and clamps, no change.

Gonna check my plugs later tonight for rich/lean - ness. I think the sound was always there, but the better I get her running the more these little things are able to be heard.


Thanks everyone !

 

[Downer]

I have the same thing almost like a hiccup it got better when I upped my pilot one size and richened the screw a bit I haven't tried to up my pilot again to see if that permently fixes it but its not that much of a bother But it it kinda does ha but I'm sure ill get it dialed in one day

 

[burns]

Have you tried spraying starter fluid (which is either I think) on the suspected areas? The idle will go up when the leaky spot sucks that stuff in.

I don't think richening things up to compensate for the air leak is the way to go

 

[EvenmoreXS]

I did try wd 40 and carb cleaner a few months ago but I couldnt get the idle to change. Thought I was good, but I still have an issue. I will try again and see if it works this time. I've had the carbs off a few times since then.

 

[EvenmoreXS]

Here are some pics of my throttle shaft seals. Im certain this is involved. I still have to change the two inside seals. These are the two outside seals. One was like plastic, and one was torn and faling appart. Brittle.

Changed gas cap rubber too. Seems to fit much better when closed.

 

[weekendrider]

When you get all the seals replaced you will find the carbs easier to tune.
Finding air leaks. WD40 used to have propane as a propellent and that is what the engine picked up as a fuel. The current epa version doesn't. And I'm not sure you could get the current version to burn with a blow torch.
Carb cleaner is hard on rubber. Period.
You may want to consider using a propane torch or one of those long bbq lighters to introduce a fuel source for it to sniff.

 

[5twins]

..... unlit of course .....

 

[weekendrider]

BWHAHAHAHA yes, if you aren't safe enough to be left alone by yourself then disregard my above post.

 

[EvenmoreXS]

Unlit........

Um.........

Do Overs ???????



Naaa, just kiddin.

I like the long ligher idea.

I Didnt know current wd40 is made from vegtable oil and baby tears.

Those seals were definitely a problem. Cant wait to idle her after i get the inside seals done. Gonna be awesome.

Just an update twins, I will check those needles when I get the carbs apart for the inside seals. I havent forgot.

Thanks everyone.

 

[EvenmoreXS]

Got my throttle shaft seals done last night. NO MORE PSSSSS sound. That will be a huge difference in performance. She likely wont shut off at the light anymore, and will be tuneable. The seals that were there were hard like plastic and one was torn and dissolving. Little Big project done. The hardest part was putting the angled carb bracket back on with the new brass fuel T. It was a small biotch. But I got it. Some cursing and threats of violence. Followed by a nice glass of makers mark.

New pipes are loud, and my baffles dont fit. I'll have to make some custom. Although, I do like the sound better than my old exhaust, just a little brite maybe.

Had to order the stupid silicon spray for my pipe wrap from the manufacturer. Local stores sell only tan wrap and silver spray. Pretty stupid if you ask me. Selling two products from the same manufacture that go together, but only stocking the products that dont go together. Like selling only 16 inch wheels and 17 inch tires.

"NO, we'd rather you buy the products you came HERE for from someone else please"

Stupids.

the pics are of the inside seals. the outside seals are super easy to change. the inside seals are too. Getting the carbs separated was harder, and that wasnt bad either.