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CRF250R ran without oil....HELP!!!!!!!!!!

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I went riding yesterday. And hit a large rock on my left crankcase cover. Split the oil filter cover, not knowing, and rode for another 20 min or so.I was riding trails,not being hard on it at all. Then, I heard a chain slap noise, for about 1-2 seconds, went away. then 30 seconds later, it came back, for 1-2 seconds,then stalled out. I grabed the clutch, and costed down the hill the rest of the way. Thats when I got of the bike and realized the sliver taken out of the oilfilter cover. I pushed it back to the truk, and didnt try restarting. There was only about 1/2 a cup of oil in the case when I drained it.No visable metal shardes. I pulled the cover, no metal. I pulled the filter, no metal. So.... my question is this.... I can put a new cover on it,new filter, and oil for around $200. See if it runs. Or should I asume I did damage and tear into the motor.(crank,bearings,topend,valves.) Where do I stop on my parts list?Whats usually the first to go on these things? And what can I expect to be damaged?THANKS FOR ANY HELP!!!!!!!!!!

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I'd put oil in try it. If it sounds bad tear it down. I really don't know how long you can run one of these engines with no oil. If it was making noise some damage has been done. Does the cam run in the head or does it have ball bearings? If the cam rides in the head that's probably the first place to get damaged. Good luck

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the valve train is the first to go in the event of oil starvation, pull the valve cover and check the cam (bearings, lobes, ect) for blueing and wear.. if it looks good then fill it up with oil and start it, keep and eye out for unusual noises and metal in the oil

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I finally had time to pull the valve cover.The only thing out of order that I can see is the cam is blued. I cant feel any mars or signs of wear. But definetly heated up. The chain,and bearings all seem fine. It was definitly dry up there... Just not long enough to do any bad damage. from what I can tell so far. I ordered my new cover and filter today. I think Im gonna follow your advise, and see how she sounds with fresh oil. Thanks again for the boost of confidence.

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I just worked on an 07 crf250r that was ran with no oil and I ended up replacing the cam, cam chain, tensioner and valve buckets. Make sure you take a good look at the cam itself and check the valve buckets for aluminum that gets stuck to them from the heat.

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Thanks sac. I will definitly be taking a second look.Like I said, i noticed the cam was blued and discolored. If there was that much heat, then the buckets must be toast. The chain is probably compromised...And if thats the case the bearings need to go. Do the hot cams kits come with bearings? I think Im gonna play it safe and do some cam/valve work. This hi/pro 4-stroke stuff is still new to me. Im used to looking more towards the crank/main bearings first when something like this happens. But I guess im not out of the woods yet. Thanks for the help... This site rocks

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most likely if your cam is blued then its usually worn and needs replacing.. check the lobe heights, exhaust rocker arm roller, bearings, exhaust rocker arm shaft, buckets, cam chain, chain tensioner (if you do replace, put a manual tensioner in there instead- way more reliable)

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The rocker arm roller seems to have alot of play. Its loose and doesnt seem right. This might be a dumb question, but how can you tell if the chain/ and tensioner need to be replaced? And who makes this manual tensioner you mentioned? Im gonna pull the cam and check the lobe heights today.and give everything else a good look.

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You may want to tear the whole engine down it sounds like you may have more trouble than I thought. It would not make sense to put a bunch of new parts into the top end and then have the bottom blow up. The question is what will not need to be replaced? What about looking for a good used engine? Thats a crap shoot as well.

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it sucks when this happens, i had some chode roost me putting a hole in my ign cover in june, i still dont have it running right, it kinda runs, but not how its supposed to, you will probally end up spending more than you wanted, but now all bad will come out of this, you will learn alot!....i think mine suffered stator damage, once it getts in the 50's i am gonna start working on it again, good luck

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You may want to tear the whole engine down it sounds like you may have more trouble than I thought. It would not make sense to put a bunch of new parts into the top end and then have the bottom blow up. The question is what will not need to be replaced? What about looking for a good used engine? Thats a crap shoot as well.

I pulled the whole top end off as well and inspected the lower end before I ruled out bottom end damage. I inspected the rod and felt for any play, thats out of ordinary, inspected cylinder and piston for any seize marks and them moved on to the top end. What year is the bike and do you have a manual?

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The bike is an 06... I pulled the top end yesterday,down to the piston/rod.Bottom end looks good/feels good. Everything looked good, besides the cam being blued. I measured the lobe heights, and were in factory spec. I also checked the valve clearances before I pulled it apart. The left intake was out .004 The rest were all good. I think I got really lucky. Or maybe i should say, I HOPE I got lucky. My case cover is coming ups today. New filter and filter cover. Im gonna fill'er up with fresh oil, And see how she runs.. Ill let you guys know this after noon the outcome....

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And yes, I adjusted the left intake. Now that I know alittle more about how these motors really work, I think what happend was the oil preasure driven tensioner, lost preasure first, loosening the cam chain, which is the chain slap I heard. Like I said origanally, The rock hit the sweet spot right between where the oil filter cover meets the case cover. It took a sliver out of the case cover, and crunched the oil cover backwards.The seal was still intact. The "leak point" was only a pin hole. so for the 20 min I rode it,, I think it still had preasure, and "pumped " the oil out slow through this pin hole. And as soon as the preasure droped, the cam chain became loose and started slapping. Then died a few seconds later....

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Nice theroy, but it's not an oil pressure tensioner. It's simply spring loaded, it will come out and not go back without a screw driver.

In fact don't try to bolt it up without backing it off first. You can break the cam chain, damage the guide and maybe the cam if you do.

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Oh Sh@%*#!! Nice call. thanks. So anyway. I got it all back together, And tried to start it.... Nothing. I pulled the plug and found it wasent getting a spark. This is were it gets weird. I kicked it over 1/2 dozen times. with the plug pluged into the coil, touching the frame. no spark. I stood there for 30 sec. scratching my head, then grabed the plug to try another plug, when it shocked the shit out of me... so........ I swaped plugs,put it back together, hooked up the fuel,and tryed to start. Nothing. then I grabed to plug wire to make sure it was on all the way, when all of a sudden a huge backfire acurred.Its like the plug is storing the energy.... any ideas?????

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I have found that after I mess with any motors they always seem to back fire right before they start. It only happens one time and then she runs but on that same note if your timing is off and it keeps popping then you want to double check your timing. It usually takes me between 3 and 10 kicks to start a motor that I have recently had apart. If it takes more then that then again double check every thing.

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Its not getting a spark. But it is building electricity at the plug. I kicked it about 15 times today. Went to take a shower. came back out and jiggled the plug wire, and wooohfffff, small backfire.30 min. after i kicked it over. Does this sound like the coil? Or the stator? I know I put the stator in correctly...

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:banana:I found a loose connection.Fixed. and The bike runs perfect... i ran it for about an hour. Changed the oil. No signes of metal.. I think I got lucky on this one. Wanted to say thanks for all the responses and all the useful advise... THANKS a BUNCH!!!:banana:banana:

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