Bike wont start at all has comp./fuel/spark

My 05 crf 450r wont start and doesnt want to fire at all and stopped running since about December after i fired it up in the garage and it backfired like a son of a gun and i shut it off and it hasnt started since. Piston has about 30 hours on it give or take a couple along with the crank, brand new gaskets and such, plug has maybe 2 rides on it and is wet with gas after trying to start it. I have posted on here multiple times before trying to figure out my problem and have checked what was advised. The intakes were close to zeroed so I just had the head rebuilt with new kibblewhite ss intakes, the exhausts were fine but i had all four seats cut because the exhausts were contacting to wide on the seat (also seals replaced, guides checked, done by a reputable honda shop). When i put the head back on the bike i timed it all up and did all the clearences so they were spot on but didnt look at the flywheel timing because i just figured that that was on. When it didnt fire i went on to checking the flywheel timeing after pondering for a while and after putting the engine back to TDC on the compression stroke I saw that the notch on the flywheel threads was just a mil. or two to the left outside of the stamped marks on the flywheel. Then i again tried to start again thinking that it might be just a fluke thing and again it didnt start. Now could this be my flywheel key or "woodruff" and would this make the bike not start at all with it haveing almost brand new, or brand new engine components, the carb is spotless, and there is spark but i obviously cant tell if it is sparking at the right time just by looking at it. Really depressed that i have had this bike for 6 months and riden it 6 times:cry:

There is a few other guys on here who have had the same problem after a rebuild, and it turned out to be that the timing chain was off a tooth.

The timing marks don't line up perfectly for some reason.

I am not sure this is your problem, but do a search and check it out.

Double check the timing and then re-check it. I had that same thing on my 03. LIke you said make sure it is TDC on the compression stoke. Check the decomp and valve clearances again. Check the spark plug and make sure you have spark. make sure gas in on(I did that once, not turn the gas on). It should fire up.

Good Luck

When I disassembled mine (five months ago) I noticed that the cam appeared to be advanced one tooth from the sight hole mark. I was told there's another mark to check, but I'll have to check my old post to remember.

But the bike was running great up until the valves bit the dust. I may finally have the money to put her back together.

Don't feel too bad. I only put 8 hrs. on my new to me '06.

Yea the gas is on, the clearences are exact, the and valve timeing is right on with the compression stroke. The other mark is on the left side crank case cover and that is the flywheel timing which if it is off would make the spark be there just not at the right time which would either make it not run at all or really shitty. I was just wondering if anyone had any input to wether or not it is the flywheel key or if it sounds like something else. When i say that it doesnt want to start i mean it doesnt even sound like it is fireing at all wether kicking or bumping

Anyone else have some input, would be greatly appreciated

Dude, I am pretty much in the same boat as you are with my 06. I shimmed the valves and cannot get it to run right. When I have gotten it started, it runs terrible. It pops and won't idle. I have changed the timing back and forth about 15 times, and still nothing. One way I change the timing it won't start. The other way I change it, it starts but runs as stated above. I am at a loss. I have never been this puzzled with a bike before, and frankly it is giving me a migraine. :p

Time the cam off the flywheel "T" mark with the slot in the threads of the oil filler cap (left side). then make sure the mark on the cam gear is dead center with the arrow on the cam tower under the cam gear (look through the slot there).

Once you know that is timed properly, then i would first get a new plug installed.

If that does not help, then remove the carb, clean the pilot jet and circuit there with compressed air. Take out the hotstart plunger, lube the piston there and then reinstall. Reinstall the carb and make sure there is freeplay in the hotstart cable. Turn on the gas, twist the throttle 2x and then kick without any gas. Should fire.

Time the cam off the flywheel "T" mark with the slot in the threads of the oil filler cap (left side). then make sure the mark on the cam gear is dead center with the arrow on the cam tower under the cam gear (look through the slot there).

Once you know that is timed properly, then i would first get a new plug installed.

If that does not help, then remove the carb, clean the pilot jet and circuit there with compressed air. Take out the hotstart plunger, lube the piston there and then reinstall. Reinstall the carb and make sure there is freeplay in the hotstart cable. Turn on the gas, twist the throttle 2x and then kick without any gas. Should fire.

I forgot you had mentioned this to me in another thread. I will check that tomorrow. Can you further explain what you are talking about as far as the mark and the "T"??? What part of the T needs to be in line with the mark?? Probably some stupid questions but I want to be sure I am doing this right. I have never had these kind of problems with a motor before. Thanks again for your help.

How is it that i get the piston at TDC and then move the flywheel to where it needs to be. That is what is puzzleing me. When i put the engine at TDC the notch in the threads is a little outside of the stamped marks on the flywheel. I hope that this is my problem replaceing valves to have the bike not start is begining to piss me off and im a Honda guy that is not happy with just looking at one sitting in the garage.

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