NX250 question on throttle control

[DesertRose]

Any other NX250 riders out there ~ I am still struggling with fixing the throttle control on my 1989 Honda.

Replaced the cables, adjusted the cables, taken to pretty darn good mechanic.

Still have sticking problem - makes fine-control hard, too, I end up jerking the gas around like a beginner.

And makes my wrist hurt - though it is a kindof de-facto cruise control :bike_rider:

Anyone have any info I'd be curious what you did to fix.

 

[goodtimes]

My guess is that you have one of three problems (in this order):

1. Sticking throttle tube
2. Sticking carb (throttle plate)
3. pinched cable

I would start by pulling the cables off of either the throttle tube or the carb (which ever is easier), and eliminate 50% of the possible trouble spots.

One other thought -- did you oil the cables? Some of the newer cables don't need oil (oil is actually bad for them), but most of the older cables need oil -- it all depends on the material used.

 

[DesertRose]

My guess is that you have one of three problems (in this order):

1. Sticking throttle tube
2. Sticking carb (throttle plate)
3. pinched cable

I would start by pulling the cables off of either the throttle tube or the carb (which ever is easier), and eliminate 50% of the possible trouble spots.

One other thought -- did you oil the cables? Some of the newer cables don't need oil (oil is actually bad for them), but most of the older cables need oil -- it all depends on the material used.

All good suggestions. Didn't oil them . . . since problem remained same after new cables, probably not a pinch . . . and mechanic worked on carb (but that does not mean it's still not the carb . . . could have been done wrong). Tube might be the problem then. Could have been damaged when it was crashed (by someone who borrowed it - was on that side).

 

[goodtimes]

How difficult is it to gain access to the carb (where the cables connect to it)?

I'd pull them off, and turn the butterfly by hand if possible. It should turn pretty easy, and snap shut when you let go.

With the cables disconnected from the carb, the throttle tube (grip) should turn easily (smooth, no gritty stuff) in both directions -- but it won't return to the 'idle' position on its own when disconnected from the carb.

My guess is that your problem will be the tube, or something associated directly with it.

Also, you might loosen the switch assembly next to the throttle tube (kill switch, starter button, etc) and move it taway from the throttle tube, just to be sure that the throttle tube isn't simply rubbing on the switch box . . . I think I'd actually check that first simply because it is quick and easy to check.

 

[mlader]

Hey guys,

My wife owned two NX250 and both showed the same symptoms with sticky throttle. With the engine off, the throttle operation is smooth and perfect, but as soon as I start the engine the stickiness returns. More RPM, more sticky it gets. It would get better after lubing the slider, but no mechanic couldn't resolve this problem. After some time I assumed that the only solution would be to change the carb. Until last night.

Recently I bought XR600R with the same problem and I started reading about it some more. I think I found the solution which applies to NX250 also. Check out this link:
http://marcelo-bbt.blogspot.com/2008/07/honda-xr-600-sticky-throttle-problem.html

I didn't try this fix on any of my bikes yet, but it looks like it's going to be a definite solution.

Hope it helps, keep us updated.

P.S.

 

[DesertRose]

Thanks so much for that great info on the carb ~ makes sense it might be the carb since the cables are new. Will see what we can do, and let you know!