2001 ST1100 throttle not snapping back

[TootTootComingThru]

Hi, first post here.

I recently bought a 2001 ST1100 and have been riding it around town but since then the throttle started not snapping back. I'm a green mechanic, but the handlebar throttle assembly part is easy enough to get to. Cables aren't frayed, sprayed some WD40 and then some cable and chain lube down both cables which seemed to have fixed the problem.
After closing up the assembly and leaving it for a bit to saturate and marinade, the throttle no longer snaps back again. It rides fine I just have to "manually" move the throttle to the closed position.

Next step is to look at the carburetor/engine end and I think the throttle body is to the back on the left side, correct? What's the easiest way to get to it? I'm hoping this doesn't require removing the gas tank.

Thank you, any insights would be helpful.

 

[Uncle Phil]

The pulley for the throttle is down on the left side at the back of the carbs.
To get a really good look at it it is easier to remove the gas tank - 4 bolts, a red connection down on the left side, 3 connections on top, and fuel line.
Easier to remove if near empty.
Then you can see the pully quiet clearly to see if there is a hindrance.

 

[JJames]

Are the original handlebars on the ST ?

 

[TootTootComingThru]

The pulley for the throttle is down on the left side at the back of the carbs.
To get a really good look at it it is easier to remove the gas tank - 4 bolts, a red connection down on the left side, 3 connections on top, and fuel line.
Easier to remove if near empty.
Then you can see the pully quiet clearly to see if there is a hindrance.

Thank you. Is there no way to get a look at it from the side by removing some of the panels? I'd rather not mess with a nearly full tank of gasoline at the moment.

Are the original handlebars on the ST ?

I believe so. One additional piece of more than likely irrelevant info is that the original owner did install a Throttlemeister and immediately removed it 23 years go. I compared the cable routing to a diagram and nothing seemed out of the ordinary and the previous owner didn't notice any issues with it when he had it.

 

[Uncle Phil]

You can but it is hard to get a good look.
Remove the saddlebags, the big screw in the center of each side panel and gently remove the side panels (be mindful of the tiny 'tab' at the back end and the three prongs - one up front, two in the rear - on the side panels that stick into rubber grommets).
Then the two screws up under the handlebar cover on the gas tank shelter and the two side screws at the rear and lift the gas tank shelter off.
That will get you as good a view and you can without removing the gas tank.
To empty the tank, hook the output to a hose into a receptacle, run a hot to the first wire on top of the tank (connector should be white and let it pump the tank empty.

 

[Streetman]

I would advise you to check te routing of the gas cables under the airbox. This turned out not to be the problem when I purchased my motorcycle.

 

[Sunday Rider]

Have you checked to see if the rubber grip is too close to the throttle housing and creating friction? I’ve had that happen.
Unusual for it to work fine and then not if the carbs weren’t taken out or throttle not messed with at the carb end.
Oh and welcome to the Forum.

 

[JJames]

Ok , I had the same problem after switching handle bars. You could try moving the front brake handle/master C a little away (inwards on the bar) or at least that it is not touching the throttle body . In my case the brake handle was pinching a little against throttle housing when i tightnd it up. This was on the under side. It took a little time for me to catch it as it looked like there was clearane from the top. Good luck .

 

[TootTootComingThru]

You can but it is hard to get a good look.
Remove the saddlebags, the big screw in the center of each side panel and gently remove the side panels (be mindful of the tiny 'tab' at the back end and the three prongs - one up front, two in the rear - on the side panels that stick into rubber grommets).
Then the two screws up under the handlebar cover on the gas tank shelter and the two side screws at the rear and lift the gas tank shelter off.
That will get you as good a view and you can without removing the gas tank.
To empty the tank, hook the output to a hose into a receptacle, run a hot to the first wire on top of the tank (connector should be white and let it pump the tank empty.

Thank you, I'll give it a go. Appreciate the detailed explanation of everything, cheers.

Have you checked to see if the rubber grip is too close to the throttle housing and creating friction? I’ve had that happen.
Unusual for it to work fine and then not if the carbs weren’t taken out or throttle not messed with at the carb end.
Oh and welcome to the Forum.

Thank you. I'll double check, but I did fiddle with the grips and started unscrewing things and fitted back in. I'll try it again.
The carbs were taken out and put back on by the previous owner last year I think. I don't know if I just didn't notice the throttle not snapping back until fairly recently, but the previous owner says he didn't have this issue when he had it.

Ok , I had the same problem after switching handle bars. You could try moving the front brake handle/master C a little away (inwards on the bar) or at least that it is not touching the throttle body . In my case the brake handle was pinching a little against throttle housing when i tightnd it up. This was on the under side. It took a little time for me to catch it as it looked like there was clearane from the top. Good luck .

Oh interesting. I'll give that a try, thank you.

Thanks for the replies and the warm welcome guys. Good stuff.

 

[wjbertrand]

To be clear, there's no throttle body on the ST1100 as it's got carburetors not FI. The cables connect to the throttle linkage as described above. The only time I had this issue with my ST1100 was due to a slight misrouting of one of the cables. I think you only need to pull the top shelter to inspect them. Check for anything that may be interfering with the movement of the bell crank as well.

 

[Sunday Rider]

Is the throttle snap back action the same if you try it when bars turned all the way to the left and then all the way to the right?

 

[Slydynbye]

You say it fixed it temporarily when you sprayed something into the cables and then it locked up?
I think its in those cables and they are now full of gunk.
Did you say you used chain lube? That can't be good, it's meant to go on and then get tacky/sticky.

 

[Larry Fine]

I remember reading that OEM Honda cables are Teflon-lined and don't require lubing.

 

[John OoSTerhuis]

I remember reading that OEM Honda cables are Teflon-lined and don't require lubing.

Correct

 

[kiltman]

I suspect it’s the plastic throttle tube causing you grief. It sometimes binds on the handlebar itself due to crud. Taking off the bar end weight and spraying WD40 between the plastic tube and the bar itself as you twist the throttle back and forth might get rid of the crud. Then repeat the process with cable lube, re-install the bar weight.

 

[TootTootComingThru]

To be clear, there's no throttle body on the ST1100 as it's got carburetors not FI. The cables connect to the throttle linkage as described above. The only time I had this issue with my ST1100 was due to a slight misrouting of one of the cables. I think you only need to pull the top shelter to inspect them. Check for anything that may be interfering with the movement of the bell crank as well.

You're right.

I feel stupid for not noticing this earlier, but I was just farting around with it and only today realized that the throttle doesn't snap back when I have the handlebars turned all the way to the left, like when I have it parked and locked. It snaps back when the wheel is straight. Is this an indication of an improperly routed cable or is there something squeezing the housing when it's turned all the way? I swear it didn't always return when going straight at speed, but I might have just imagined it or something.

I suspect it’s the plastic throttle tube causing you grief. It sometimes binds on the handlebar itself due to crud. Taking off the bar end weight and spraying WD40 between the plastic tube and the bar itself as you twist the throttle back and forth might get rid of the crud. Then repeat the process with cable lube, re-install the bar weight.

I did that earlier today as well, thank you. Seems a bit more loose and less gritty now.

 

[jfheath]

Also - check that you have some slack in the inner cable. There are two cables, one to pull the pulley on one direction, the other pulls the pulley in the other direction. If you adjust them so that they are tight - all you are doing is trying to pull the pulley up towards the tank.
The cable can become tight as a result of altering the adjusting screws, or by routing the cables differently - the outer cable takes a slightly different route from the inner cable - so you can make the inner cable pull tighter, just by flexing the outer.

This is why it is necessary to get the routing correct, and why you should check that the engine revs do not rise or fall when you turn the handlebars.

 

[bdalameda]

If you have either the throttle open or throttle close cable adjusted too tight, the throttle will not snap back. Try giving the return or throttle close cable adjuster a little slack and see if it snaps back better.

 

[wjbertrand]

It should snap back closed the same way regardless of handlebar position. If your bike is fitted with handlebar risers, I think the cables need to be routed differently to stock.