Carb piping

[woody_1010]

hey!

Im trying to piece an st1100 engine together and need some help

there are 2 plastic t-piece's on the carbs, one on each pair in the middle. What are these for??

thanks

 

[Mark]

Which pieces?

Here is an online fiche of the ST1100_carbs that you might use to identify the parts.

 

[woody_1010]

in that picture its piece number 5



its the pipe coming out between the carbs in this picture

 

[Mark]

The tubing going down from that T goes to the air filter (right?); so, I think the T is part of the vapor recovery system.

 

[Rossi]

The tubing from that T goes to the little filter at the front of the airbox shroud. It leads to the space under the rubber diaphragm in the carb. It is at atmospheric pressure.

 

[woody_1010]

thanks for the replies!

at the moment, the engine is on a workbench, the plan is to put it in a dirt buggy!
all i have is an engine, no other parts of the bike!

should those two t-pieces be piped out of the way of the engine and left then?

 

[Mark]

Without the stock air filter the ST1100 engine does *NOT* run well.
Without that little air filter attached it runs *very* poorly as well.

 

[woody_1010]

ok, is there any reason the engine doesn't run well with out the stock air filter, what makes it so special?
and il try putting those two pipes to a small air filter

thanks for the help

 

[Mark]

I know that the bike doesn't run well without an air cleaner.
But although I know you have to have one, the 'stock air filter' part might be incorrect.

So... let us know!

The 'air filter' on the 2 lines is a made of foam; so, don't go overboard on that 'air filter'.

Good luck!

 

[BuddingGeezer]

ok, is there any reason the engine doesn't run well with out the stock air filter, what makes it so special?
and il try putting those two pipes to a small air filter

thanks for the help

The jetting of the ST1100's carbs are set for the air filter. Without the air filter the fuel mixture is TOO LEAN. My '91 will only rev to 5500rpm with out an air filter in neutral.. I once ran an Amsoil foam filter. With the filter properly oiled (not too much oil) my bike would loose power at full throttle. Ran fine the first 7/8 of throttle, open her up she would stumble. The Amsoil filter flowed too much air and it ran too lean. I installed a Fram and the bike runs perfect.

 

[BuddingGeezer]

I know that the bike doesn't run well without an air cleaner.
But although I know you have to have one, the 'stock air filter' part might be incorrect.

So... let us know!

The 'air filter' on the 2 lines is a made of foam; so, don't go overboard on that 'air filter'.

Good luck!

Good luck![/QUOTE]

Go down to where lawn mower parts are sold. Usually they have a green foam air filter material. This works great for that little foam filter.

 

[The Dan]

The tube is so there is filtered air going in and out of the top of the sliders when they slide up and down. If not then they would fill with dust and screw up.

 

[George]

hey!

Im trying to piece an st1100 engine together and need some help

there are 2 plastic t-piece's on the carbs, one on each pair in the middle. What are these for??

thanks

All the info ya need is in these notes...

Get ye to a breaker and pick up a stock air filter box. Should be cheap as there's plenty of parted-out STs and little call for the air box.