i just got this 03 crf 450 from the local dealer, used. I know the previous owner now, and it was well taken care of as per the manual instructions. The bike is very clean and I put 15 hours on it before it started to go south. I have been trying to get it fixed around here but my dealer was trying to cheat me . The next closest dealer is 150 miles away. Anyway, the bike was having a hard time starting. I must have kicked it 100 times before it started the last time, following the procedures in the manual. when it finally did start, it ran fine, now problems at all starting hot, even after dropping it. The next time it would not start, period. Turned out it had no spark (stator went out) so I fixed the spark problem and it has spark now. For some reason though, it still wont start and when I pull the plug out, it is not even wet. Putting gas in the head makes it want to start. Just kickin it gives a foot long flame out the back and backfires. What gives? is it my valves? is it lack of fuel? help me out guys, I am starting to hate my honda, thinking yzf
'03 crf starting problems
- Thread starter crwtf?
- Start date
You may want to check the valve clearances. Hard starting is a symptom of tight valves. It's an easy job and a good place to start. Also, have you adjusted the idle at all? If you've messed with it, return it to the stock setting (I think it's around 2 turns out), the '04 is very finicky about it's idle.
It is also worthwhile to check the adjustment for the auto-decompressor while you are in there checking the valve clearances.
If your plugs not even wet but it fires when you pour gas in the (head?) try a larger pilot jet and and turn your idle up a little til it warms up. It's easy to do and worth a try. I went from a #40 pilot to a 42 and , altho its been at least 45 º every time I have tried starting the 04 CRF250 it has started within 4 or 5 kicks. I, also was having a terrible time starting it cold before. My CRF has never been a smooth idler like my YZ250. I hope it is just that I havent gotten it jetted just right. And it smokes when it's cold, which bugs me causeI don't know why, the Yamaha does'nt.
- Thread starter
- #5
okay, I dove into the bike ready for the worst after reading pages and pages of too tight valve stories. From what I gather the valve springs are crap and in turn mash the valves into the seats hard over and over decreasing the clearances and tightening up the valves. once the engine is warm, however, the metal expands and the clearances increase again so the bike will run (which sounds like what I described). I checked the clearances and the exhaust valves were spot on at .011". The decompressor clearance seemed right too at the book prescribed .028". The intake valve clearance, however, seemed way too tight. I could not get the .006" feeler gauge under either intake valve unless I stuck it in and advanced the motor by hand making the cam lobe sort of push it in. I also read on the offroad.com project crf deal that they had a valve tightening problem that led to lots of kickstarting that led to not starting. They suggested the Kibblewhite valve kit. Does anyone have any experience with this kit? does it sound like I have the problem pegged? thanks guys
Thump
Jr Admin Type
- Jan 17, 2000
- 4,656
- 7
I've never had a problem so my thoughts are kinda simplistic... Could it be bad fuel or a carburation/jetting problem? The airfilter is clean? Are you sure your starting procedure is not the problem? I know when my CRF is cold (both my old 03 and the 04) the first thing I do after I turn the gas on is wick the throttle open 2-3 times, pull the choke and kick, once it is warm NEVER wick the throttle open before starting.
The intake valves in the CRF450 are titanium and are generally the ones that exhibit the recession problems that close up the clearances. The Kibblewhite stainless steel valves and spring kit is the best solution to the problem. We haven't had any further issues with engines that we have fitted with the Kibblewhaite valves and springs.
Mike Perry the head of R&D for Kibblewhite was kind enough to share the specific details of the problems with us in the threads below.
http://dirtrider.net/forums3/showthread.php?s=&threadid=61322
http://dirtrider.net/forums3/showthread.php?s=&threadid=55155
Mike Perry the head of R&D for Kibblewhite was kind enough to share the specific details of the problems with us in the threads below.
http://dirtrider.net/forums3/showthread.php?s=&threadid=61322
http://dirtrider.net/forums3/showthread.php?s=&threadid=55155
I think you may have your decompresser lever out of spec. You say your exhaust valves are spot on at .011 which is measured by "in". If your measuring with "in", the you need to add .014 to make the decompresser clearance at .025. If you have it set at .028 its out of spec.
I also have an 03 CRF450 and this information is on page 27.
Good Luck !!
I also have an 03 CRF450 and this information is on page 27.
Good Luck !!
- Thread starter
- #9
I am sorry, I checked my notes (always take notes on your bike guys, trust me, it pays off) and my decompressor clearance was actually .025" instead of the .028" I listed. I think that I am going to try the Kibblewhite kit. Its relatively cheap insurance and it aint like the #(&%(@$# thing is going anywhere now. Thanks guys.
I had similar experiences with my 04 crf450. last time I took it out bout a month ago it took, I dunno, a thousand kicks to get going.. Yesterday it wouldnt start I tried over a hundred kicks.. I took the plug out and it was black so I scraped the plug with a knife (no sandpaper) I put it back in and it started literally first kick. I would have replaced the plug but the dealer said he didnt get any yet for the 04's. I have learned when it is cold bump up the idle by at least half a turn, choke outl, and two or four full snaps of the throttle then it should start..
