[henthorpe]

Hello,

I have a 2002 Crf450r that I have owned for about 5 years now. Every winter I put my bike into storage as I live in Minnesota and don't ride in the winter. I recently tried to get my bike going again after having parked it in September of 2016. When I parked it then, it ran perfectly fine. However, when I just tried to start it, it acted like it was seized. I could kick it over a few times, but then it would become extremely hard to kick. I was able to get the engine to spin past this lock point, but then the same thing happened and I decided to stop trying. I took out the air filter, took off the exhaust, took out the spark plug and saw no indications of any problems there. I drained all the oil, which looked completely normal, checked the oil filter which also looked fine. I didn't have time to take it apart anymore, but I am just completely stumped as to what could be the problem.
I have done some work to the bike in the past;
new clutch basket 3 yrs ago
replaced every valve component 2 yrs ago
manual cam chain tensioner

This is the first problem I have ran into with this bike, I only replaced the valves because they were very worn out, but the engine was running fine when I decided to do that. No blow up etc. Any thoughts appreciated.

[JimDirt]

Welcome to the site !!

You could have a issue with the auto de-compressor sticking on the cam , you would need to check that it operates freely and returns to position , the only other thing i can think of is somehow that the clutch plates are sticking together causing the tightness you feel
, so lay the bike on its ignition side and pull the round cover off the clutch , work the clutch lever with the cover off and see if everything is working freely , with the clutch lever pulled in (tie it off so its fully against the grip) , use your fingers and try and move the plates (putting your hands on opposing sides so you can lift evenly) , and see if the plates all are free , but my first guess would be the de-compressor , then the clutch as most likely suspects

Report back with findings ...

[henthorpe]

Welcome to the site !!

You could have a issue with the auto de-compressor sticking on the cam , you would need to check that it operates freely and returns to position , the only other thing i can think of is somehow that the clutch plates are sticking together causing the tightness you feel
, so lay the bike on its ignition side and pull the round cover off the clutch , work the clutch lever with the cover off and see if everything is working freely , with the clutch lever pulled in (tie it off so its fully against the grip) , use your fingers and try and move the plates (putting your hands on opposing sides so you can lift evenly) , and see if the plates all are free , but my first guess would be the de-compressor , then the clutch as most likely suspects

Report back with findings ...

Thanks, I will look at that and give an update. Might be some time before I do though.

[henthorpe]

Welcome to the site !!

You could have a issue with the auto de-compressor sticking on the cam , you would need to check that it operates freely and returns to position , the only other thing i can think of is somehow that the clutch plates are sticking together causing the tightness you feel
, so lay the bike on its ignition side and pull the round cover off the clutch , work the clutch lever with the cover off and see if everything is working freely , with the clutch lever pulled in (tie it off so its fully against the grip) , use your fingers and try and move the plates (putting your hands on opposing sides so you can lift evenly) , and see if the plates all are free , but my first guess would be the de-compressor , then the clutch as most likely suspects

Report back with findings ...

Update: I started by taking off the clutch side case cover, inspected the clutch and kickstart but saw no problems there. I removed the clutch and then took off the valve cover. My cam chain was probably a little tighter than it should have been but I loosened it and took of the camshaft and saw no fault there. At this point the crank was free to rotate without anything else in the motor spinning besides the counter balance. Spark plug out. I took off the left side case cover and looked for anything out of place there but again found nothing. The problem persists after taking all of that stuff apart. I had an allen wrench socket on the crank trying to spin it and it felt very smooth and made no sounds when spinning but again it would just hit a "wall" and no longer want to spin, and I did not try to force it past that point. I would say I could get the crank to spin freely and easily maybe 180 degrees but like I said, it would just seem to stop.

[Aussiecrf230]

Perhaps a spot of gum or rust on the bore catching the rings as you turn it over?