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Why is it hard to start my 04 crf 450r?

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I just bought a CRF 450R i am 5.8, 180 pounds and when i tried to kick it over it start well the first time, i ride it for about 15 minitues when back to get goggles and turned off the bike. Walk back out side and i could not start the bike when it was off, my dad tried to start it and he had no luck with it. We left the bike for about a hour and my brother came home jumped on kicked it about 20 kicks and got it started.

When my brother was riding it he stalled it, and had some trouble starting the bike a guy was driving buy and said turn off the gas lay it down to the left and let the gas drain out and then picked the bike back up turn the gas back on and kick it and repeat till the bike starts.

Why is it so hard to start?

Why is so much gas comming out that i have to tip it over?

why is there so much commpresion?

and how can i make it easier on my self so i can get it started?

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Why is it so hard to start?

Why is so much gas comming out that i have to tip it over?

why is there so much commpresion?

and how can i make it easier on my self so i can get it started?

Why is it so hard to start? Valves need to be adjusted or replaced

Why is so much gas comming out that i have to tip it over? Float bowl stuck

why is there so much commpresion? Because its a 450

and how can i make it easier on my self so i can get it started? Grow 2" or find a tree to lean it up against when you are trying to start it. If your valves need adjusting look at the decomp valve also. May need adjusting.

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Why is it so hard to start?

Why is so much gas comming out that i have to tip it over?

why is there so much commpresion?

and how can i make it easier on my self so i can get it started?

ok you got a lot of stuff going on here. 4 strokes don't like starting when they're hot, which is why you have a hot start lever. That might explain why after your bike sat for a little while your brother was able to start it. Also, like the other guy said, it could be your valves that need to be adjusted/replaced. Are you giving the bike throttle when you're starting it? This is another no-no for your bike.

As far as tipping your bike over-- I'm no expert, but it's my understanding that when you tip your bike over all it's doing is draining fuel from the bowl which won't have any impact on your bike starting or not. If your float is stuck open then it's going to drain on it's own without you having to lean your bike over. If you've managed to flood your bike then it wasn't because your float is stuck open.

Your bike is a race bike and thus has a high compression ratio. If that's new for you then it might seem like it's hard to kick. If it's harder to kick then it should be then either your timing is off or your compression release is out of adjustment. Probably not your timing because then your bike would be running like crap and you'd be complaining about lack of power. I'd guess either you need to adjust the compression release or like the other guy said....get something to stand on. Hope this helps!

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as some have stated, 1st thing to check valve clearance. Your likely pretty close to 'zero'. Having ridden an 04 for MANY years, (and also have an 08 as of a few months ago) i can tell you any crf450 prior to 06 has the valve seat material in the head that is harder on valves (than 06 and later heads). Once the 02-05 gets hard to start, this is often the cause and something that should be done from time to time anyway.. so no waste. :smirk:

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Both of my 04's I bought did the same thing as you describe. I tookboth bikes apart to basically do routine maintenance such as air filters, lube suspension, etc. Both bikes had dirty air filters AND plugged pilot jets from sitting.

Replace your pilot jets and check your valves. Mine happened to bespot on at. 006 and. 011.

Joe

PS. My bikes now start 2nd kick now when cold or hot. In addition, make sure bot start lever moves freely!

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Thanks very much thumpers Talk for pointing me in the right direction. I have a crf450r 2007.after some rebuilds it was so hard to kick over and start. I checked tonight and yes it seemed it was a tooth out on the timing marks. Also the small decompression pin which fits into the sprung plate was not located. Took me a couple of hours, result I can start it easily with training shoes as I used to. Thanks again thumped talk. By the way on this model the decompression is not adjustable.

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Thanks very much thumpers Talk for pointing me in the right direction. I have a crf450r 2007.after some rebuilds it was so hard to kick over and start. I checked tonight and yes it seemed it was a tooth out on the timing marks. Also the small decompression pin which fits into the sprung plate was not located. Took me a couple of hours, result I can start it easily with training shoes as I used to. Thanks again thumped talk. By the way on this model the decompression is not adjustable.

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I just bought a CRF 450R i am 5.8, 180 pounds and when i tried to kick it over it start well the first time, i ride it for about 15 minitues when back to get goggles and turned off the bike. Walk back out side and i could not start the bike when it was off, my dad tried to start it and he had no luck with it. We left the bike for about a hour and my brother came home jumped on kicked it about 20 kicks and got it started.

When my brother was riding it he stalled it, and had some trouble starting the bike a guy was driving buy and said turn off the gas lay it down to the left and let the gas drain out and then picked the bike back up turn the gas back on and kick it and repeat till the bike starts.

Why is it so hard to start?

Why is so much gas comming out that i have to tip it over?

why is there so much commpresion?

and how can i make it easier on my self so i can get it started?

 

Hard to start could be many things. Has the bike been sitting for months? Does it pop sometimes when kicking? If yes to either, clean the carb, especially the pilot jet. If not, pull the plug and make sure it has nice visible spark that strikes a couple/few times with a good kick. If it does not, replace it. The problem could also be you, are you twisting the throttle at all? Twisting the throttle even a little bit while trying to start is what you do when you don't want your bike to start, so make absolutely sure you're not doing that by keeping your hand off the throttle while kicking. After that, I'd go ahead and check the valve clearances, but note that the common problem with these is for the intake valves to close up, which lowers compression and makes it kick over more easily than normal. So, if the bike has tons of compression, I don't think your intake valves are closed up, but go ahead and check them last.

 

Why is there so much gas coming out that you have to tip it over? You didn't mention anything about lots of gas coming out, or where it's coming from. Is it the overflow hose on the carb? If the bike is losing gas out of the carb overflow, clean the float valve and also check the float height adjustment. For the float height adjustment, the little tab should be roughly parallel with the other horizontal lines on the other areas of the metal tab, if that makes sense. If you're just thinking that there's lots of gas because the guy driving by said so, gotta take it with a grain of salt. 

 

If there's lots of compression and if the bike is hard to start, that sounds like the cam chain is not timed correctly. Definitely check the cam timing. Did the previous owner claim to have recently adjusted the valves? If yes, there's a good chance it's wrong, because it's really easy to do since the marks suck and don't really line up even when you do it right. I see folks talking about high compression like it's normal, but it's not. Any 250 smoker is twice as hard to kick. These 450's are pussycats with auto-decompression. I can start mine with my hand, but not even close with a two stroke of half the displacement. 

 

To make it easier on yourself, start with the above and hopefully something in there will fix what's making it fussy.

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Hard to start could be many things. Has the bike been sitting for months? Does it pop sometimes when kicking? If yes to either, clean the carb, especially the pilot jet. If not, pull the plug and make sure it has nice visible spark that strikes a couple/few times with a good kick. If it does not, replace it. The problem could also be you, are you twisting the throttle at all? Twisting the throttle even a little bit while trying to start is what you do when you don't want your bike to start, so make absolutely sure you're not doing that by keeping your hand off the throttle while kicking. After that, I'd go ahead and check the valve clearances, but note that the common problem with these is for the intake valves to close up, which lowers compression and makes it kick over more easily than normal. So, if the bike has tons of compression, I don't think your intake valves are closed up, but go ahead and check them last.

Why is there so much gas coming out that you have to tip it over? You didn't mention anything about lots of gas coming out, or where it's coming from. Is it the overflow hose on the carb? If the bike is losing gas out of the carb overflow, clean the float valve and also check the float height adjustment. For the float height adjustment, the little tab should be roughly parallel with the other horizontal lines on the other areas of the metal tab, if that makes sense. If you're just thinking that there's lots of gas because the guy driving by said so, gotta take it with a grain of salt.

If there's lots of compression and if the bike is hard to start, that sounds like the cam chain is not timed correctly. Definitely check the cam timing. Did the previous owner claim to have recently adjusted the valves? If yes, there's a good chance it's wrong, because it's really easy to do since the marks suck and don't really line up even when you do it right. I see folks talking about high compression like it's normal, but it's not. Any 250 smoker is twice as hard to kick. These 450's are pussycats with auto-decompression. I can start mine with my hand, but not even close with a two stroke of half the displacement.

To make it easier on yourself, start with the above and hopefully something in there will fix what's making it fussy.

This post is from 2011. Lol

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This subject helped me a lot. In a couple of hrs last night I cleared up my problem, crf450r so hard to kick over and start. Yes the timing was out 1 tooth, and on 07 version the decompression is not adjustable. I could probably start with my hand now, thanks mate's.

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This post is from 2011. Lol

 

Haha, guess I missed that one. 

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