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Hi all

In the continuing saga of the 450x refresh....

I finished the JD Jet kit, and air box mod. However - while putting everything back together I realized that the throttle isn't closing / snapping shut. I have to pull back to close the throttle.

I've inspected the cables and throttle body of the carb. I see no issues (but I haven't completely disassembled).

I don't see any kind of spring other than the torsion spring in the diagram. That spring is relatively visible once the cover is off, and I can't see how I could have f'd that up with anything I was doing.

-Other thoughts that are in the area
. the throttle adjust screw/cable was seized. I busted that loose and lubed and worked in/out
. JD Jet kit already mentioned
. Airbox mod
. pulled carb up from intake/frame for AP mod/o ring
. it's an '05 450x with <10 hours on it (cables? sudden death?)
. cables and throttle working fine a few days ago
. wtf

Any thoughts or advice is appreciated.

I am guessing when you pulled the carb you inadvertently mis-adjusted the cables at the carb itself , and/or you routed the cables wrong and they are getting pinched by the gas tank , and/or where they go thru the triples down by the radiator , if when you turn the bars all the way to the left and it gets better then that is your issue , the 2 adjustments should be , 1 all the way down and tight , the other with the locknut is where your adjustment for slack is , if it does not have slack at the tube , then you need to loosen the locknut and screw in the adjuster with the bars all the way to the right , till it frees up , also , if you removed the throttle tube for any reason , it might be binding if you tightened down one screw all the way , then the other , it needs to be even so nothing binds on the tube , also make sure the throttle housing has some side to side slop , if the housing is pushed all the way into the bar (pushed to the left) , then it can hold the end of the grip/tube to the end of the bar and hold it from operating freely

Basically , its either a bound up cable , and/or the adjustment is too tight and there is no slack where the cables go to the throttle , personally , i tighten both all the way down , and leave myself plenty of slack , also I make sure of the routing , as the 2 combined will bind it up for certain ..... , remove the tank , if the throttle frees up , then you have the cables in the wrong location as they cross the valve cover , and/or , they are pinched by the radiator , and/or the adjustment is off , turning the bar from lock to lock will tell you if its adjustment , and the tank off will tell you if its getting pinched

Also , pay close attention when reinstalling the tank fuel line , look at the coil power wire plug , try to move it and make sure its on snug , then push the gas line/petcock thru , and lower the tank , being careful not to pull the wire off the connector , it happens frequently , and you don't want to solve one issue and create another

Grit inside the throttle tube is common, especially with hand guards where goo can get in the end and cause friction. Quick and easy to fix.

I have pinched throttle lines plenty of times when putting the gas tank back on. A little wiggling into a more roomy spot for the cables is necessary.

A couple of additional notes

The tank is still off - I actually noticed the friction when I put the cable cover back on

Also- I didn’t remove or adjust either of the throttle cables when I did the other work

And- it’s binding just laying on the frame. It’s not even on the intake boot or down in the cavity between the shock and intake.

I’ll check the effects of full left and right lock- fwiw...

Grit inside the throttle tube is common, especially with hand guards where goo can get in the end and cause friction. Quick and easy to fix.

I have pinched throttle lines plenty of times when putting the gas tank back on. A little wiggling into a more roomy spot for the cables is necessary.

Seems weird that the grit would show up (so to speak) all at once. No prior issues.

The gas tank isn't installed.

It might sound silly but maybe worth seperating the cable and the carby to confirm which is the problem. If only for the sanity benefits.

If it is the cable and it still does it when in pretty much a straight line then it might be worth removing it and checking for a frayed wire. Flushing/ lubing from throttle end till it comes out the carby end with some wd40 or the like might prove beneficial as well.

I know you wouldn't expect a cable problem with so few hours.

It might sound silly but maybe worth seperating the cable and the carby to confirm which is the problem. If only for the sanity benefits.

If it is the cable and it still does it when in pretty much a straight line then it might be worth removing it and checking for a frayed wire. Flushing/ lubing from throttle end till it comes out the carby end with some wd40 or the like might prove beneficial as well.

I know you wouldn't expect a cable problem with so few hours.

That is what I was thinking to - and what I did yesterday. The bad news is that it confirms I'm a bit of a dolt (should have just said OK rather than posted back my thoughts on probability of it being the cables). The good news is that it's obviously on the cables. As soon as I removed the cables the carb started snapping closed and acting normal.

The top end of the cable assembly is apart now (quite a bit of grunge up there) and I've run about a 1/4 cup of cable lube through each of them. Letting them drip for now. I did order another set as a backup plan (pleasantly surprised at the price)

I'll need to reassemble - does anyone have a link to a reassembly procedure/checklist/... anything? I'd prefer to only do this once.

As always - Thank you for the help.