Sticky throttle.

Just had the bike out for a short test run, first chance I have had since the last time I stripped the carbs down. The throttle is still slow to close and is sticking open often enough to worry me a bit. I know two of the slides were a wee bit slow coming down when I did Ricks clunk test but only once the caps were on, they dropped like a guillotine before that.

I have fitted a brand new throttle cable and routed it as per the manual so I think it must be the slides but I really don't want to go through taking the carbs off again. Taking them off is easy getting the sods back on is another matter. I'm wondering if there could be another cause or if there is a reason I should'nt take the slides out from the top ( with carbs still attached to the head) and give them another going over with wet & dry.

Appreciate any ideas.

Faighaigh.

 

When you let go of the throttle it should snap back. If this is the problem you are having it is not the slides.

 

faighaigh,

I am having the same problem with mine. When I twist the throttle and let go, it's very slow to go back to idle. I had this problem before I cleaned my carbs and since I cleaned them, the problem still persists. The springs are pulling the cable back down, so it's not the cable for me either. I guess I'll have to pull the carbs again. Frustrating! But I'm only firing on 3 cylinders, so I'm going to have to troubleshoot that anyway.

 

maybe something is gettin rubbed up in the twist throttle

 

I should have added that winding her up can be worrying as well. Sometimes when I open the throttle nothing happens for a second or two then she suddenly roars off. When I close the throttle it snaps back fine but the engine does'nt slow immediatly and when you swing round a bend and find yourself just a few metres from an old boy and his herd of goats you need the engine to respond pretty quickly.

Faighaigh.

 

my seca 750 does it too.it will snap back quick but the rpms are slow to come back down. i think its an airleak.

 

If the carb linkage is snapping back like you say, it sounds like some sticking slides and/or the chokes(enrichment) are not seating or adjusted correctly.

 

If they falling-fast with the Hat and Spring OFF ... sealing-up the top should cause them to be real smooth ... no sticking.

You might have all the bases covered -- "Cleaning wise" -- but, still have a sneaky air-leak causing you the headaches.
Extra air and a Pilot Mixture Screw (or two) adjusted a bit too RICH will keep the rev's up.

You mention a new cable.
Use the cable-slack adjustment feature, up at the top, to make sure there's sufficient free play and the cable isn't being tugged a little bit by the cable being tight.

If you have a situation where your AirBox-to-Carbs Boots have hardened-up, over the years, you might need to add a little "Air-tight security-smear" of sealant around where the Boots attach to the Carbs big Airbox-side intake.