Sign in to follow this  
Followers 0
sasarris83

New WR450 owner... Need some Help

35 posts in this topic

Hey I'm new to the site and have some questions about my 2006 WR I just bought. I didn't know what was done to the bike so I went through and checked all the free mods and most were for including grey wire, throttle stop and ais removal. So the bike started and idle poorly if at all had dead spot at quarter throttle and hard starting as well. So I got a JD jet kit, new air cleaner, new gas and an after market fuel screw. Complete all the work set the fuel screw at 1 1/4 out and the bike has way better throttle response and crispness which is awesome, BUT it still will not idle with the choke off and believe me the bike is warmed up. When the choke is off I need to keep blipping throttle to keep it running and if I let it sit for a second without giving it throttle and then try giving throttle again it will die. Does anyone have any clue as to what the heck is going on?

Also idle screw is buried all the way in.

Please help!!!

Share this post


Link to post
Share on other sites

By the way I'm running a 170 main, 48 pilot and 3 groove from top on blue needle. I had the 42 pilot in as per JD but it was worse with the 42 so I put the 48 back in. Still will NOT idle even with idle screw all the way in. Runs great on choke.

Share this post


Link to post
Share on other sites

Your pilot, and possibly the passage above it, are partially clogged.

Replace the pilot with a NEW one, and shove some mono-filiment line up the passage to make sure it's clear.

You have to adjust your fuel screw properly to get a real result.

Start with the idle as low as it will go, then raise it with the fuel screw.

Repeat as needed to get the smoothest idle.

Edited by Krannie

Share this post


Link to post
Share on other sites

It will barely idle with the idle screw all the way in so making any kind of adjustments while its running isn't going to happen. I did forget to mention that its about 30-40 degrees here in NY right now but I don't believe that would make such a harsh effect on how it idles....but I will get the carb out and blow out the pilot circuit with air

Share this post


Link to post
Share on other sites

You need an aftermarket longer air/fuel screw, which will allow you to do the fine tuning that is needed. The stock Pilot Jet is a 42 isn't it? If so, then a 48 should be about right for 30 to 40 degree weather. You should get a good idle somewhere at 2 turns out from a lightly seated in position on the air/fuel screw, not the idle screw.

Share this post


Link to post
Share on other sites

It already has an aftermarket fuel screw, which doesn't barely make a difference in the idle no matter where it's set. When I first took the carb out it had a 155 main and 48 pilot. The JD kit has me using the blue needle on the 3rd groove down, 170 main and 42 pilot. I thought maybe it wouldn't idle because of the pilot, so I took the 42 out and put the 48 back in. It helped a little but still won't idle.

Share this post


Link to post
Share on other sites

Is there an obstruction in the air box? Like a rag between the filter and carb? (Don't ask how I know)

Share this post


Link to post
Share on other sites

I have an 06 with free mods also....bike has an aftermarket header and pipe....

at 40 degrees I run 52 pilot and 170 to 172 main....fuel screw is about 2 or a little more out....

as previous poster stated double check pilot is clear all the way threw, did you install washer on fuel screw, also try running it out to 2 or even 3 than working back in if it will idle

sounds like its lean...

Edited by race4fn

Share this post


Link to post
Share on other sites

I just bought a slip on, no header. But I'm running the 170 and 48.. The fuel screw was in it when I bought the bike a few weeks ago and the washer and oring are in place.

I'm not obviously going to be riding in these cold temps especially because we just 8 inches of snow but I feel like this thing should at least idle without the idle screw all the way cranked in and having to blip the throttle...

Also I have fuel screw out 1 3/4 now and really doesn't make a difference. The thing is I can't get it to stay running long enough to make an adjustment. This is really my only issue because one it is running its rev's nicely and has crisp throttle response and no dead spots or bogs. If I could get it to idle I'd be set.

Share this post


Link to post
Share on other sites

does it idle with choke out? maybe your not warming it up long enough...

im no expert on these at all, just personal experience, bike takes awhile to warm up

Share this post


Link to post
Share on other sites

I've let it idle on choke until the pipe got cherry red and take the choke off and it dies quickly.- that was with the 42. Air jet was clear. Why is the 48 too big? I loosened up the carb and spun it sideways to pull the bowl off and blew through the pilot jet passage way with compressed air. I just got it back together and I'll start it up tomorrow and see what happens.

Share this post


Link to post
Share on other sites

Unless you run a un-muffled pipe and no air cleaner, you shouldn't need a 48 pilot jet.

A 45 should be fine.

A 48 will work, but you'll have to put the fuel screw in at .5-1.0 turn, which means you will not have enough adjustment left for air pressure changes.

If removing the choke makes it die, it usually means a pilot jet circuit extreme leanness.

Just using compressed air up the passage is not enough, if you have ethanol poisoning of the carb.

You have to spray real carb cleaner up there, and use a large mono-filament line to completely clear it out.

It is an S shaped passage.

So, you are saying that if you turn the idle screw in, to get it to idle, it will not idle?

Edited by Krannie

Share this post


Link to post
Share on other sites

Yea my next step is to do the dreaded removal of the carb so I can really clean that passageway out. Ethanol is killing us!

With the choke it actually runs perfect and when I take the choke off the bike will die no matter where the idle screw is set. It is currently all the way in as far as it can go and the bike will idle for a few seconds and die. Actually if I back that idle screw out its harder to start unless I blip the throttle while I'm kicking.

Share this post


Link to post
Share on other sites

Yea my next step is to do the dreaded removal of the carb so I can really clean that passageway out. Ethanol is killing us!

With the choke it actually runs perfect and when I take the choke off the bike will die no matter where the idle screw is set. It is currently all the way in as far as it can go and the bike will idle for a few seconds and die. Actually if I back that idle screw out its harder to start unless I blip the throttle while I'm kicking.

That is the classic symptom of a clogged pilot jet and passage.

Share this post


Link to post
Share on other sites

Ok so I put my new pipe on and started it up today. I set the idle screw one turn out and then started turning the fuel screw out. I had to start the bike a few times because it wouldn't stay idling but finally got it to idle normal at 4 turns out. Turned it back to 3.75 turns and that seems to be the sweet spot. Is that ok? I'm guessing its not because the fuel screw is so loose it's just going to vibrate out.

Share this post


Link to post
Share on other sites

Made adjustment per manual and now idle screw is cranked all the way in and I'm at 2.25 turns out on fuel screw... Sound ok?

Share this post


Link to post
Share on other sites

Ok so I put my new pipe on and started it up today. I set the idle screw one turn out and then started turning the fuel screw out. I had to start the bike a few times because it wouldn't stay idling but finally got it to idle normal at 4 turns out. Turned it back to 3.75 turns and that seems to be the sweet spot. Is that ok? I'm guessing its not because the fuel screw is so loose it's just going to vibrate out.

You are not following the procedure.......

Start with the fuel screw at one turn out.

Start the bike, and set the idle screw so it will barely idle.

Turn the fuel screw to raise the idle as high as it will go with the fuel screw.

If idle is too high, lower the idle with the idle screw, and repeat.

Keep doing that until you get the smoothest idle.

Motor must be HOT before this will work.

Choke and hot start must not LEAK for this to work.

You then fine tune the fuel screw at 1/8 in turns, blipping the throttle, looking for the fastest idle drop and the smoothest idle.

When done, if you fuel screw is less than 1 turn out, you need a smaller pilot.

If it's more than 2 turns, you need a bigger one.

If it's more than 2 turns with a pilot larger than 48, you have an air leak.

Some carbs/motors, due to the condition (lots of hours) might need a 48 pilot.

Share this post


Link to post
Share on other sites

You said to turn the fuel screw one turn out and set the is screw to where it barely idles...which I did...the catch is to get it to barely idle the idle screw has to be cranked all the way in.

So from there I turned the fuel screw up until the highest idle I could get was about 3-4 turns out which I mentioned the screw being very loose at that point... Then backing off on the idle screw finally worked well like you said and the idle smoothed out and really normal and responsive. But I'm stuck with a loose fuel screw... So maybe I'm still not doing something right?

You said I might have an air leak.? Where? Intake boots? Worn out motors need a 48 pilot?

Also I believe the hot start and choke orings are good. They look good and when you turn either of them off the motor responds quickly so that leads me to believe they aren't leaking by...

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0