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HELP NEEDED

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I just bought a 2004 crf450r. It will not start. The guy I bought it from said he had to tow it with a golf cart to bump start it. The air filter wasn't oiled or even connected. I'm assuming it needs a valve adjustment and maybe a piston. This is my first four stroke so I'm new to this hole thing. Are my valves so far out of adjustment that it won't start? I took out the pilot jet and I couldn't even see light through it. I cleaned it out and cleaned the carb but it still won't start. Any help would be appreciated. And if someone could tell me the stock jet sizes that would be awesome. Thank you for your help in advance

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I would try to get your money back. Buying a bike that has a dry and/or non-attached air filter gets you the worst possible bike out there. Oil changes were surely neglected as well. Bike likely needs valves and head work and also a top end. If you're lucky...

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I just bought a 2004 crf450r. It will not start. The guy I bought it from said he had to tow it with a golf cart to bump start it. The air filter wasn't oiled or even connected. I'm assuming it needs a valve adjustment and maybe a piston. This is my first four stroke so I'm new to this hole thing. Are my valves so far out of adjustment that it won't start? I took out the pilot jet and I couldn't even see light through it. I cleaned it out and cleaned the carb but it still won't start. Any help would be appreciated. And if someone could tell me the stock jet sizes that would be awesome. Thank you for your help in advance

 

well tatty...

a bit of research before purchase would have saved you a bit of grief.  The likely hood that your valves are trash is high seeing how its a 2004.  When they go out of adjustment it generally means that the chromium nitride coating on the valves has come off as a result of running dust through the engine (lots of hours and or bad air filter maintenance).  When the hard coating is gone, the soft and abrasive titanium is exposed and subsequent valve adjustments will be in vein, lasting only a few rides before needing to be readjusted.

 

Your best option is to get a complete head from big bore thumpers.  They buy new Honda heads and install stainless steel valves, large springs, and titanium retainers.  With proper air filter maintenance the head should last a long long time this way.

 

Who knows when and if its ever had a piston in it?

or crank?

 

with its unoiled non installed filter this points towards horrible maintenance.  So, maybe it would be best if you put a piston, I recommend an OEM or CP high compression piston.  You need to check out your crank shaft while your at it.  You should think about replacing your cam chain just for good measure and adding a manual cam chain adjuster.

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Well thanks for the help. I bought this bike for $1250 so it's not like I paid a ton of money for it. But now I'm wondering of its worth spending more money on or just trying to sell it

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How would I check the crank? What signs of wear am I looking for? And how likely is it that the valve seats are bad too?

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 have a 03 man I put kibble white vavle in it after dropping a stock titiaum vavle in the head think it cost me 200 bucks to to rebuild the honda from back then were made with alot of new light wiegth parts and the vavles go out of spec in about 20 to 30 hrs of tracdk riding odds are the vavles are out of spec to the point where it get the motor spining fast enough from a the kick starter hence why it would run from a pull start. Odds are you just need to do a vavle adjustment. I know the bike shops around me will trade you for your old shims making this basically a free to fix problem. Also I would suggest getting the clymer manual for about 40$ as good as honda manual and way easier to read. Don,t give up on it yet the old honda 450 are super cheap to fix. These guys are just pestamest. And if the bike has been sitting for a long time the filter will dry out i wouldnt worry about it to much unless you see alot of sand/dirt in the head when you pull the vavle cover. Its a dirt bike ride hard and fix it

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I don't think I'm going to give up yet. I checked the clearance on the valves and there was 0 clearance on the exhaust and and .011 in / .279 mm on both intake. The clearance on the decompression arm was a whopping .043 in / 1.092 mm. Might not need intake valves but I'm replacing them for good measure. I'm going to put stainless steel valves in it too.

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