Starting problems, used 2004 wr450f

I am new here and I appreciate the accumulated knowledge of of all of the members. I have been reading the posts for situations similar to mine and can't find what I need. If you can direct me or offer your ideas I would be very appreciative. Here goes.

2004 wr450f

bike sat for awhile before I bought it. I was told it was ridden last fall.

changed oil cold knowing I would do it again with a warm engine.

new battery

no spark

checked connections but you know how that can go.

checked continuity on the things in the manual.

kill switch, ignition button, magnito seem okay in terms of continuity.

not sure how to check stator, was told I needed to check peak voltage.

primary coil above spark plug should be .08-.10, I get .00.

secondary coil is in spec.

(if my terms are correct the primary is the two prongs at the top of the coil and secondary is the top of the coil connected to where the top of the spark plug enters)

Then, I did something and got spark (don't know what).

put it back together and it started right up first kick.

shut it off after awhile and it started first kick four times.

put it in gear holding clutch in and it jumped forward and stalled.

started it again and it did the same thing.

now I am back at the beginning with no spark and primary coil reading .00.

Does this sound like a bad coil and problems with the clutch plates for having sat for so long?

Also, pulling in the clutch seems to have no effect. I can not roll the bike with the clutch pulled in and the bike in gear. I have tried adjusting it at the handlebar lever, no change.

I might have multiple problems here and may just have to take it to the shop but I am trying to avoid the $80/hr they would charge me if this is something I am able to fix myself. Thanks in advance, Todd.

Edited by Hof

Interesting. First things first. Let's leave the "lurching" problem out of the equation until we can get this starting reliably. Did you use a new sparkplug while working on this bike? Sometimes, an old plug just won't reliably ignite inside a high-compression engine, so use a new plug. And NEW fuel!!! Pump gas is horrible fresh, much less being old!!! Give us some more to go on, and we'll all try to help out. Maniac

You may just need to rock the bike back and forth with the bike in gear and the clutch lever pulled. Is the clutch arm on the engine move when you pull the lever up top?

(You are correct about which are the primary and secondary ignition systems on the coil)

I really wouldn't be surprised if it is a bad connection, either corrosion or loose or broken wire/pin.

Best of luck

Spark plug was brand new

Gas was fresh, I dumped out the old stuff.

In reply to second the second post, the clutch cable is being pulled my the lever and I can watch the arm on the engine moving when the clutch is pulled. I also put it into second and tried pushing in by gravel driveway with no luck. I was hoping to warm up the engine and maybe loosen it up that way but I can't start it yet.

I will try the connections again. Since it started well a few times I just need to track down the electrical glitch.

I agree, lets sort out the starting issue and then worry about the clutch.

You are probably measuring pin to pin inside the coil, if you are and getting 0 then your coil has an internal short. Try to verify that you're not accidentally touching leads when you check the pins and that there's nothing down in the connnector possibly crossing it out. If neither of those have happened then chances are the coil is kaput. Depending on how it's shorted it can have a weak spark under the right conditions.

Disturbing things can sometimes get them going for a while at least. It can also indicate a poor connection so make sure to check the terminals inside the connector.

The clutch could just be "Stuck". If the engine has a real weak spark it would stall real once you put it in gear. Even a known good bike is stuck until you jar it and make it move the first time.

Yank the float bowl bottom off the carb and if there is junk in it additional effort may be required. ...but start there as far as the carb/gas and getting the bike started is concerned.

You don't know anything about the bike's history ? Just that it was running last fall ?

If it looks trashed maybe a few other areas of interest would be necessary (e.g. clutch plates perhaps ?)

What I know of the history is that it was advertised with 32 hours of engine time and a new dirt digger clutch. The exterior of the bike has less than what I would call normal wear for a 2004. I can tell that the previous owner did basic maintenance but could have done better.

i recently went through starting issues on a 2004 wr450f that had been sitting for several years.

the carburator had lots of gunk build up inside it. The petcock was also completely clogged with gummy stuff. I would yank the carb and do a complete cleaning of it and put in a new pilot jet.

its good you dumped the gas and put in fresh stuff, but the other crap was sitting in there for months = goo... pull the carb, clean it out (may need to replace pilot jet) and re-install.

You are dealing with two seperate problems. Get the thing running and idling in neutral, and then sort out the clutch issue..

Bought a new coil on e-bay, should be here today or tomorrow. I will pull the carburetor but, would the carb make it so there would be no spark? When I did get it to start it ran well and only stopped when I tried to put it into gear.

Thanks for all of your ideas, I will post when the coil gets here and what I find out along the way.

Okay, got the new coil, plugged it in and there was no difference. I kept checking connections and nothing. I put on the battery charger for a couple of hours during the evening. The next morning I went out and pushed the start button and got spark. I put the tank on and it started right up and it starts up consistently. I have no idea why. I am worried that out on the trail it might revert back to not starting again.

I also put some 'Sea-Foam' into the oil and let the bike idle for a while and now I am able to use the clutch and roll the bike forward and back while in gear but not very easily. I think I will change out the oil again to keep trying to remove any of the bad gunk still in there. I am a little reluctant to tear into the clutch because I don't know much about doing that but I will if I have to. I know it is the best way to learn how to service my own bike in case of future problems.

The local mechanic swears that the stator is the problem with the no spark issue. I just don't know. I will keep plugging away at the maintenance stuff that was neglected until I am certain I have done all I can on my own.

If anyone has any further ideas as to what to check or do I am all ears. I have done or checked what every one has suggested so far and things seem to be working out. Thanks, Todd.

Yup, I think I have an idea for ya:

Clutch pin switch.

Since the bike has electric start there is a neutral sensor and a pin switch for the clutch lever allowing you to start the bike in gear with the clutch pulled in or it should bypass if the bike is in neutral. I am thinking a couple things:

1. It's corroded and not working that way because it's bad and should be bypassed or replaced.

2. It's been knocked out of place, so then just put it back in.

3. Because of your clutch issues you may have too much freeplay in your cable and it doesn't make 100% contact. Just push the lever out and see if that helps. Adjust the cable once you get the bike running.

4. Lever was replaced with an aftermarket YZ unit that isn't relieved for the switch.

5. Could be the neutral sensor I think down by the countershaft sprocket has come off or not making good contact.

Can't remember if you said you have the manual but try to find the wiring diagram and trace out those connections.

Guessing it's the clutch perch switch.

It's early AM for me so I might be full of it.


Well, at least were kind of getting there! I think Mike might be onto something there! I always disable my clutch switch so I forgot all about it on yours. One thing you can do is after you've got your bike running, while idleing, I pull the clutch in and hold it in for 30 seconds or so, before putting it in gear. This allows some engine oil to get between those clutch plates loosening them up before being placed into gear, lessening the chance of the clutch "lurching". After the bike is warmed up, takes about 1 minute, you should be able to place it into gear without it stalling, hopefully! If so, then slowly start easing the clutch lever out. If the bike starts "jerking" out from under you instead of ever so gently, smoothly creeping out from under you, you've probably got a grooved up clutch basket. If so, it's easy enough to eye-ball it and see by just removing the outer-most cover. Keep us informed! Maniac

OK, I think I have the starting problem fixed. I mentioned last post that I got spark but did not know why. The previous owner cut and cobbled up the wiring for the lights. In one section near the rear light he patched in on the yellow wire a 2 inch section of wire and just twisted the wires together and left it. The wires for the headlight area looks like a birds nest of wires. I had been trying to start the bike with the headlight switch off. I noticed that when the bike was running today, the switch was on and I turned it to the off position and the bike shut down like I had just hit the kill switch. I will try to track down this problem when I tackle the lights themselves. But for now it starts with ease.

I actually rode the bike today. The clutch plates are still sticking. During my little rides I can shift gears but if I slow down to a crawl it wants to stall. Maybe that is just normal for this bike. While the bike was sitting between rides up and down the driveway and I was putting things back together, the clutch seemed to go right back to its stuck position. I started the bike , put it into second gear, gave a push with my legs and got it rolling and was able to ride again. Looks like I am probably going to have to get into the clutch and see what is going on.

Glad to hear you are getting somewhere and may at least have some idea what's up. I dug through the original posts and didn't see mention anywhere of a rats nest of wiring or I know far earlier I'd have told you to sort that out first before anything. Not trying to bash you, but that info is one of those things that helps a long distance diagnosis, however I may have simply missed it.

Oh yeah, US WR's never came with an on/off headlight switch so you have a bunch of non-stock shit to sort our BEFORE continuing on with the clutch.

Clutch issue:

Not sure when you say running at a crawl what you mean by that. I take it as a walking pace and depending on gearing (are the sprockets stock?) may be normal. Mine with a one tooth larger countershaft sprocket will putt at like 5 mph so I think you may have another issue. In the OP you said motor has 32 hours on it and a new "dirt digger" clutch. And either the PO was really hard on the clutch or was someone who liked to dink around with stuff as 32 hours is very low on a stock clutch. Never heard of a Dirt Digger as well, brand name? Either way, once you:

1. Verify your gearing is stock and running gear are ready to go; chain and sprockets are adjusted correctly and both in good shape, tires inflated correctly and clutch cable is good and not binding (all thing that can hide or enhance what may feel like a clutch issue)

2. Sort out your wiring issues and see how the bike runs after

then it's time to pull the clutch cover and look at what the hell is going on in there. If your like me and have no patience for leaving a motor open for days, I'd try to find a good used complete stock clutch on eBay and be ready to swap parts. If you plan on keeping this bike you will eventually need another basket and other clutch parts so it's a good investment for probably under $50.

Hope this helps.


You are right about the wires. I honestly did not think the wiring for the headlight could be the root of my problem since my problem was an engine problem. I just did not think it through enough with my original post.

As far as the clutch, when the bike sits for even minutes it wants to bind up. I can pull in the clutch and try to roll the bike forward and the rear wheel just slides across the floor. If I put the bike into say fourth or fifth gear I can get the wheel to roll and then everything loosens up and it rolls no problem. If I let it sit for a few minutes it goes back to the beginning of not wanting to roll at all.

I plan on taking a look at the clutch tomorrow to see what it is like in there.

you should look at this article

What causes a worn clutch basket & how to fix it

it really helped me fix my clutch and I'm new to bikes it's got pictures and step by step instructions on how to do it.hope this helps and good luck

The starting problems are solved. An after market headlight switch is acting as a kill switch. As long as I leave the switch in 'headlights on' position it starts just fine.

As far as the clutch, I took it apart today and cleaned the plates. There was no grooving to any of the parts but it looks like the PO or POS as I have been calling him, did not do much to prevent moisture from entering the crank case. I could see drops of water inside the clutch and my recent oil change came out milky. I am not losing coolant into the area or it would have been blue. I believe that the moisture bound up the plates. Once they were cleaned and put back together the clutch worked fine on my ride around the yard. However, I still think there is still too much moisture in there. After letting it sit while I worked on other things it is binding again. I am going to have to find out how to get it dry once and for all. Any thoughts? Thanks, Todd.

New plates. Not really a way to dry them and you really want to start fresh. Steels should be fine, just replace the fiber ones, shouldn't be too expensive.


New plates. Not really a way to dry them and you really want to start fresh. Steels should be fine, just replace the fiber ones, shouldn't be too expensive.


+1 :thumbsup:

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