Whats up riders,I have a 96 CBR F3 and i have a oil seal leak beind the front sprocket that connects to the transmissiion i believe. I cant seem to get the sprocket off and I cant turn the bolt to get the sprocket off. Is there a certain tool i may need or a certain procedure to remove it? I broke a ratchet I had but it was cheap anyhow. What should i do to remove the screw that secures the front sprocket that is wrapped with the chain? I put it in gear and tried to loosen it but it wouldnt loosen,thats when i broke the mechanisms inthe ratchet. Any suggestions? I got pics of the the problem area and this is witht he chain off already.

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Use an impact wrench, if you have access to one. It's the easiest method I've used. Takes about two seconds to remove. Or, you can try a really long breaker bar.

 

You don't need an impact wrench (though it does work). You can do it with regular hand tools. Follow the procedure here:
http://cbrworld.net/forums/thread/257864.aspx


However, this will not solve your problem with the oil leak. The oil seal that is on the countershaft must be replaced from the inside of the tranny. You can't get to it from the outside.

 

So im going to have to split the case just to change that seal that sits behind the sprocket. Split the case is saying take the whole engine out,correct. Im mechanically inclined and i have the time to do it. Not really in a rush and would love to learn how to do it. When i had the bike in neutral it was really hard to move in reverse,could that be other signs of things to come? The gears still shift all the way through,its just I had trouble moving in reverse and then along comes the oil leak from the sprocket seal. What does it entail to fix the seal and am i better off taking it to the shop? Thanx

 

You are looking at a pretty involved job. People really experienced with working on these motors might have some short cuts, but essentially the airbox and carbs will need to be removed; motor will need to be dropped from the frame; clutch, stator, oil pump, oil cooler, water pump, all need to be removed; cams, cam chain, and head will be removed; then you can split the case and pull the transmission shafts so you can pull the main oil seal off and replace it. You can find the full factory manual online for free, or go witha Clymer (less than$30). I'm guessing a shop will probably charge over $700 for labor alone to replace the less than $20 seal. Itis not an impossible task todo it yourself, just have patience, an organization system, and a good place to work...as well as the special tools.Some tools that are useful (and/ or necessary)include a rear bike stand (ebay),clutch holding tool(used a Motion Pro tool), flywheel holding tool(strap wrenchcan work), flyweel puller (factory tool about $10), 27mm socket, breakerbar, torque wrenchs (most of the case bolts use a verylight torque, and awrench calibratedfor up to 250 N/m is notaccurate for low values...and you will just stretch and snap bolts waiting forthe torque wrench to"click").

Regarding not being able to rollvery easily backwards in neutral...not sure what that could be. Could bea bearing issue? Doing a teardown like this, you probably will want to replace some things "while you are there".

Hope that helps your decision, one way or another.

 

Good newsI only had to replace the crankcase oil seal behind the sprocket and I didnt have to splot the cases.

 

How were you able to do it?

I'm dealing with this same issue and got a little scared when I saw what everyone said it would involve. I was thinking I'd try just shooting some silicon sealant in there first before I took everything apart. But if I can change it easily that'd be great!

Thanks for the help!

 

Also, does anyone have a part number for that seal? I can't find it anywhere. What's the official name for that part? I've been searching for "front sprocket oil seal".

 

I just replaced my seal but not to sure ifs did it properly, on the sea itself it had a little rubber lip around the seal and when. I pushed the seal int the axe that rubber lip ripped off all the way around the seal I started the bike and let it run and no oil came out so I'm thinking I'm good.. Butninhave to fill up the oil to proper leveli all leaked out cuz of the seal