2005 honda crf450 cant get the idle right & is

If the problem start after putting Vance & Hines Pipes, then try to sync the carbs, if not possible (meaning turning the sync screw all the way and cant sync them), reJet the carbs with 1up, slow and main Jet.

hiya sounds like your float in the leaking carb is sticking. this will cause the problems you have. check and clean float system in carb, check for leaking float too.

Try to adjust valves sometimes small gap will cause engine to respond rough if valves are not adjusted. Good Luck.

Go easy on twisting the throttle. Every time you twist, a shot of raw gas goes into the carb. The bike will flood easily. Put in a new spark plug, clean the air filter and drain the carb float bowl. Then get a can of starting spray. Spray into the air filter and then try to start it. The gas valve is turned on isn't it? Please rate my answer. Thanks.

you jet for altitude.. I don't know of these bikes but id start one size up on main jet & also one up on idle jet if this carb is so equipped ..if carb has needle see if you can raise it to next level also if it has a clip & grove arrangement..lok for a nice tan color on plug isolator tip after some run time .. & also how the bike feels ..

It doesnt matter if the jets are stock or not it is a myth that the jets must be bigger when you put a stage one kit in. Remember stock jets are there for EPA standards and what size works to pass is what the manufactor will use. I have many times put smaller jets in a carb even on race bikes to get a better performance. I hope this helps.

my 2001 just had that problem. Take off your air cleaner and look in the carb. There is a plastic venturi there that sticks. it will free up with your finger

Basic setting for idle adjustments is ~1-1/2 to 2 turns CCW from CW stop. New stock (paper) air filters don't require re-jetting--only K&N foam replacements require one size bigger main jet. Adjust each carburetor idle screw for smoothest idle. Each screw should be about the same adjustment--if one is non-responsive, that carburetor may need internal cleaning. Make sure you have good spark plugs and the ignition points are clean and set to proper clearance. The ignition coils on these old Honda's were typically weak--try to find a modern replacement. The carburetor slide needles should have the 'C' clips in the center groove. Make sure the retainers are down tight. Check the engine valve clearances (about 0.003 " cold) for both valves when the crankshaft is set for TDC when that cylinder is coming up on compression.