VF500 - Throttle sticks with airbox installed

I recently purchased an '85 VF500F. I rode it for a few days without any issues, then decided to tear into it and get any maintenance stuff out of the way. After putting it back together, I discovered that the throttle was sticking. I traced the problem to the airbox.

When the airbox is out, everything moves smoothly, but when I install the airbox, the front of it pushes down on one of the throttle cables and binds it up. I messed around with it for a bit, but couldn't figure out how to get the airbox on without binding up the throttle cable.

Everything worked fine before I started working on the bike, and I never touched the throttle cables. Is there a trick to getting this to work?

 

Does your bike still have the carb heat guard/cable router? #7 in this pic:

 

Nice looking ride Mobtown. I just bought one just like it except those F1's would look better on mine.

 

Can you post a pic of it ALowe? I have my carbs out right now. If I can compare your cables to mine...we might figure this problem out.

 

I'll get some pictures when I get home.

Mobtown - I do have that heat shield. I removed it and reinstalled it when working on the bike. The cables pass through the slot like I would assume they should.

The previous owner did replace the throttle cables sometime recently. I'm starting to wonder if maybe they aren't quite the right length of if they're routed a little differently. On the other hand, it worked fine before I took it apart, so there has to be some way to make it work.

 

Not sure what to tell you to be honest...the cables should at no point come in contact with the airbox...so how the two might be related is a mystery to me. Maybe you can tell us how you traced the problem?

 

Good idea, I'll write my congressmen and see if they'll look into it.

Here's what it looks like:

Top View


Side View


Side View with Airbox - It pushes down on the top cable.


Similar angle without the airbox.


Overall view to show how the cables are routed. Does that look about right?


I messed around a little bit and got it so the throttle doesn't completely stick, but it's a little sluggish when you let go, and I'm a little afraid something will move while I'm riding and pinch a cable.

Should those two other cables be running between the throttle cables? One is the choke cable, the other is an electrical cable of some sort (never bothered checking).

 

No fraying that I can see.

Is there any way to adjust the angle of the bracket the cables go into? If that was at less of an angle, I think the cables wouldn't be forced to bend as sharply.

 

Your cables look the same way mine are routed but my cables do not have anything between them. Wouldn't think that would be a problem though. I have my cables disconnected at throttle tube...if you could grab both ends of the cable and manually push and pull both ends....do they feel like they are dragging? Since you have this apart I would disconnect the cables from the tube slide the tube off..clean the inside of it and the handle bar..lubed those up(not with grease or lithium those lubricants will gum up) and now with the cables disconnected you get can some lubricant down inside the cables. It's kind of pain but it's definitely worth the trouble.
Oh if you decide to take the throttle tube off....if your starter button is working good...I will advise you not to remove it from the main housing. Don't worry it is held in the main housing with a screw so it won't fall out on you.

 

So I decided to spend the $10 and get a cable lube tool, and I wonder why I didn't just do that in the first place. The throttle moves better than ever now. I think lubing the cables is the only maintenance item I didn't perform. That should teach me.

Thanks for the help everyone.

 

A cable lube tool? Never heard of it.