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03 CRF450R- Trouble Starting?

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Bike went from starting on 1st to 3rd kick every time to taking like 50 kicks. Happened overnight. Was not gradual and no other modifications or new parts were added to bike.

Wondering if I should:

Clean the carburetor?

Install new spark plug?

Adjust valves?

Suggestions?

Thanks.

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is it hard to kick? not start but kick?. i would start by checking the easy things like hot start and make sure it is not stuck open. while your at the carb there is no harm in cleaning it. then move on to your spark plug then if all checks out decompression lever and your valves. just check the clearances and shim if needed. no harm in replacing your spark plug ;p while you are checking your top end soak the carb in cleaner to get all that nasty ethanol out!

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valve cover off.. check intake valves. they-be-tight. THat's what ya get for not checking periodically. One ride it runs great, next ride your kicking all afternoon. (i learned the hard way too).

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Rooney03- No change in compression, kicks exactly like it always has. Thanks for the input, I'll check the Hot start and carb first. Thanks.

Dan

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Rooney03- No change in compression, kicks exactly like it always has. Thanks for the input, I'll check the Hot start and carb first. Thanks.

Dan

your not getting it.. The decompresson mechanism takes away tons of compression, but that lever spins out and gives the exst valves full seal after 600rpm. If the intakes are even a little tight it will feel the same when kicking.. your bike has a minimum spec of 65 or 78psi during a compression check (cant remember if 78psi applied to the 03 or just the 04 and up).. you understand that a bike making only 78psi would never run right? 185psi is pretty good.. but that isn't considering decompression on starting.

Your wasting your time chasing hot start and carb. Pull the friggin valve cover off and slide a feeler gauge in there. If it is in spec, you didn't waste any time anyway as you clearly have not checked them before.. it is something that should be done regularly and takes about 15 mintues even if you never did it.. 5-10 after a few times.

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Thanks Greg! I'm on it.

no worries! just like to see people riding more, and spending less time working on a bike. I have had my share of issues, and often get help on this site. Now, im not saying you don't have a carb issue, i would just start with the valve clearance spec.

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no worries! just like to see people riding more, and spending less time working on a bike. I have had my share of issues, and often get help on this site. Now, im not saying you don't have a carb issue, i would just start with the valve clearance spec.

hmmm maybe i am just a rare case. my bike starts first to second kick cold and first hot and my intakes were zeroed out haha. figured out that is what my whirring problem was as well. ordered some new KW in and stock ex and cant wait to get em all back together :bonk: hope you find the problem soon

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hmmm maybe i am just a rare case. my bike starts first to second kick cold and first hot and my intakes were zeroed out haha. figured out that is what my whirring problem was as well. ordered some new KW in and stock ex and cant wait to get em all back together :bonk: hope you find the problem soon

they may not be "zeroed out" , you just don't have a small enough feeler gauge to stick in there. When they are truely zeroed, you will be kicking many times to get started, IF it starts.

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they may not be "zeroed out" , you just don't have a small enough feeler gauge to stick in there. When they are truely zeroed, you will be kicking many times to get started, IF it starts.

nah i have a .0025 feeler and i also tested with a stip of paper. nada haha they were cupped to all hell and literally zeroed. glad i checked when i did.

had jsut bought the bike from a guy so im doing all new top end after christmas

new piston,rings,valves, and probably full fmf pipes

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nah i have a .0025 feeler and i also tested with a stip of paper. nada haha they were cupped to all hell and literally zeroed. glad i checked when i did.

had jsut bought the bike from a guy so im doing all new top end after christmas

new piston,rings,valves, and probably full fmf pipes

They could still have been at .002 (sheet of paper is like .004 btw) and you'd never notice a difference between .002 and factory spec.

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