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2008 450 exc problems

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Still new to dirt so sorry I did search.

I can not get it started, I rode it around 2 weeks ago and came back from school this weekend to sell another one of my bikes. So I rolled the bike out of the garage and tried the electric start and it clickes but no luck, not even close to really sounding like it was about to start. Then I tried the kickstarter and definitely had no luck. I read that the electric starter could cause problems so I did what I read and disconnected them to try just the kickstarter but again no luck.

I tried to pull the spark plug to check it but was not sure what size socket I needed.

Also- I had been having a hard time getting it started last time cause the battery would not charge so I would always have to kick start it, but even that was hard when the bike was hot. So I tried to get a new battery and had it plugged into the bike this morning, since I could not get it started I put the old one back in. So also maybe this helps as well.

Any help would be greatly appreciated thanks to all.

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There could be a couple of problems here. Its an 08 exc have you pulled the epa stuff off and rejetted with a JD Jet Kit? The bike comes CARB legal for Cal. so its very lean. Second you could have flooded it and you need to change the spark plug and the wrench is in your tool kit. Third you could have an early model that decompression unit was installed wrong and is 180 degrees out and is not working. That can be a warrenty issue and your dealer can help you with that. With fresh gas, rejetted EPA removed and fully charged good battery not a cheap Chinese one the bike should start.

Edited by ktmfred300

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There could be a couple of problems here. Its an 08 exc have you pulled the epa stuff off and rejetted with a JD Jet Kit? The bike comes CARB legal for Cal. so its very lean. Second you could have flooded it and you need to change the spark plug and the wrench is in your tool kit. Third you could have an early model that decompression unit was installed wrong and is 180 degrees out and is not working. That can be a warrenty issue and your dealer can help you with that. With fresh gas, rejetted EPA removed and fully charged good battery not a ceap Chinese one the bike should start.

Didn't know the tool kit had the spark plug tool but just got it out. It was a little bit wet from fuel and slightly dark. It is sparking as well.

the only thing so far that I have noticed with the desmog stuff done was the previous owner did the exhaust and the catch can. I think everything else is still the same on the bike.

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Bikes fu**** I only rode it one time and blew the engine. I should of checked but the guy showed me a receipt for checking the valves and an oil change and said he hadn't ridden it since that service. Well went out and checked and No Oil in the bike !!!

I really don't know what to do. I only got 30 miles on the bike.

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the biggest part of the desmog is the small vacum inlet in front of the carb. it is a small line about 1/8" that has a brass nipple threaded into the intake tract. that HAS to be removed and PLUGGED, and all of the lines that connect to that and the vacumn block that is on the frame just inside your left ankle and of course the vacumn canister that is inside the left side panel/rear fender.

as far as clicking and not starting, 1st, ofcourse, put the batt on a real charger not a trickle, and let it charge at 2amps for at least a day or 2. while that is happening, disconnect the battery and clean all of the battery connections and wires. while it is disconnected, take out the 2 bolts that hold the starter in. they are 8mm head bolts.

slide the starter out, it is sealed with an o-ring where it goes into the cases so sometimes it is a bit tight, try rotating it some while pulling. some guys have said they have needed to hit it with a rubber mallet or dead blow hammer, but i dont like that idea if it is not absoluetly neccesary.

try to listen to see if you hear a springing metal sound when the starter comes out, because that may mean the starter shaft and gear may have been stuck engaged.

try kicking the motor over slowly while the starter is out but not trying to start it just turning it over.

i put just a little good grease on the gear and the guide shaft on the end of the stater.

if you are comfortable doing it, you can reconnect the battery while the starter is out of the bike and turn the ignition on and crank the starter over, just remember to have a GOOD grip on the starter because it will want to jump and flip around.

put it all back together and see if it cranks over once the batt is fully charged.

if the starter cranked over fine when out of the bike, and the kick starter turned the motor over then you could have a bad battery.

try jumping the bike from a car, if it cranks and starts your battery might be bad.

take out the plug and see how hard it is to kick over. it will still be tight but it should kick over much easier.

if it is all testing ok but it is hard to kick and hard to crank, your auto decompressor may be bad and you are trying to start or kick it over at full compression and that aint gonna happen.

a few ideas to try, hope it helps

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Maybe you need to have a dealer check your bike out things don't sound good that there isn't any oil in the motor. Have a leak down test and compression test.

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compression came to only 60

Not good it should be 150-180. Could be a valve or rings. Who ever owned the bike before did something that motor just doen't crap out like that.

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The crappy part was I came home this weekend to take it to the track tomorrow and do an oil change today. Figured I would get the other battery and all that on first. Then we were going to take a trip over spring break (2 weeks away) to go trail riding. Going to be tearing into it over spring break now. Hopefully for how bad it is now it will be on the better end of things.

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Sorry to hear about your luck. Pull the drain plug and see what the deal is. (metal shavings, etc)

If it ran out of oil, you could have lower end issues as well. You might be better off finding a ebay/CL motor for it.

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I took out the bottom drain bolt after looking at the site glass and saw nothing. Only a few drops came out. I just got an email back from the guy saying he checked it two days before selling it to me. There is no oil on my garage floor under the bike. Were could the oil of gone?

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I took out the bottom drain bolt after looking at the site glass and saw nothing. Only a few drops came out. I just got an email back from the guy saying he checked it two days before selling it to me. There is no oil on my garage floor under the bike. Were could the oil of gone?

how much is in the tranny side? Could this be a case of the oil migration problem often discussed on this site?

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how much is in the tranny side? Could this be a case of the oil migration problem often discussed on this site?

I don't think so. I think mostly the oil transfer problem causes the oil to go into the lower part of the engine.

Can someone tell me what all I am looking at now with this problem and how much it is going to cost me?

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Put oil in it and it started up, but I hear a hollow ticking noise now coming from the cylinder area.

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Don't freak-out my 08 450excr has that same sound, it's normal,especially if you have an aluminum skid plate. Also you have to reroute the crankcase breather hose down to the overflow collector. I put a loop up next to the shock then down and actually tapped in a 3/8 barb fitting.

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I almost forgot, the noise might be your cam chain tensioner if you haven't already you should change the stock one out w/ a Dirt Tricks unit..Problem solved

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my oil went from the engine side and migrated to the trans not the other way around, i dont know why unless it is a different seal problem...the pressurized side of the engine oil pushed the oil over to the non pressurized trans...uh oh :banana:

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my oil went from the engine side and migrated to the trans not the other way around, i dont know why unless it is a different seal problem...the pressurized side of the engine oil pushed the oil over to the non pressurized trans...uh oh :banana:

Wait what? lol if this is making fun of me that's fine, I just want to find out what happened.

Don't freak-out my 08 450excr has that same sound, it's normal,especially if you have an aluminum skid plate. Also you have to reroute the crankcase breather hose down to the overflow collector. I put a loop up next to the shock then down and actually tapped in a 3/8 barb fitting.

I had the skid plate off

I almost forgot, the noise might be your cam chain tensioner if you haven't already you should change the stock one out w/ a Dirt Tricks unit..Problem solved

Anywhere specific I should look this up to possible purcahse?

Edited by leland

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drain the trans oil and see how much oil is in there....mine was high and engine was low

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