My brother was riding my bike (2001 cbrf4i) when for no reason the engine locked up causing him to wreak. Now it will not start but makes a grinding sound and the engine still seams to be locked up. i have not done any work on the bike so it is still stock. it only has 8,00mi on it.
does anyone have any idea what may have caused this.

 

Hope your brother is o.k. As for why it locked up there's no telling unless you tear down the engine. Could've dropped a valve or broken a connecting rod or 100 other things. With proper maintenance those engines are usually bullet proof -- especially if left stock.

 

Damn, I hope your bro is alright!!! Sounds like a seized piston. If the starter is grinding then you definitely have internal problems. Also, check the front sprocket, as I have had numerous accounts with my and others bikes where the countetrshaft nut backs out and the chain gets jammed.[8D]

 

You guys are scaring me, I didn't ride as hard today as I usually do. Too many worries....

 

Thanks guys. My brother is fine. to put it like he did "I have wrecked my bicycle worse than I did your bike." To tell you the truth he is extremely lucky because he was tossed in to the other lane but there was no traffic. He only got a little road rash on his arm but it is the size of a quarter. SO LUCKY! [sm=devilangel.gif]But as for my bike I have not even thought about taking it apart yet. Too much work, school, and not enough money (it also hurts to see my baby like that). But I plan on working on it soon. Thanks for you guy’s input, I will post when I find out more.

 

as far as why something like that would happen i wouldnt know, but i had an f4 tip over and not want to turn over at all, bought new starter and all, not even that! turns out oil made its way to the top of the piston and kept it from turning over. took out all the plugs and hit the starter and it was like striking oil. replaced plugs and ran fine again, litttle on the smokey side for a day!