Hi! I am new here and hope to find some info on this old bike. My father purchased this 1971 250 F81m second hand back in about 1974. been in the family ever since!

I recently got it down home here in Mo. The bike is in near perfect sondition for its age! I have been riding it around the back roads and south of here around the creeks and hills. Lots of fun!

Anyway, to my question. Recently the bike started running eratic, fouling plugs and the likes. i discovered that the cylinder base gasket had blown chunks. So i pulled it apart, made a new base gasket, and decided to reuse the head gasket as it is copper. (hopefully it will hold up). BUT, I cannot find ANYWHERE the head bolts torque. Thier are 4 larger bolts that hold down both the head and the cylinder to the crankcase, and 4 smaller bolts that just bolt the head to the cylinder. Unfortuanatly the original manual got water damaged and is unreadable, CRAP!

if anyone has info on this bikes head torque, please let me know. I am getting desperate!!!! LOL!!! i wanna ride this ol rig some more before the snow flies this winter!!!!

Thanks

 

Man, I haven't the foggiest idea on specs for that thing....

You might try these guys. Buy a manual and it should have all the specs, etc, you need. http://www.repairmanual.com/motorcycles/1971/34/4/4418

That link should go right to the book for your bike.

Enjoy your stay!!

 

LOL!!!!!!!!!!

I know most folks wont know a thing about thi ol bike! Just gotta check!


thanks for the link. looks like it will be of some GREAT help!

 

NP...

Oh ya...It's worth a try. You need to get us some pics of that sled of yours man...

 

Will do.....

Got the head back on, and went ahead and torques it down with some "generic" numbers. Did 36 ft/lbs on the main bolts, and did 24 ft/lbs on the smaller ones. felt good when they were snugged down. right or noit? I dont know, but it holds up so far.

Now the SOB is STILL fouling out plugs and back firing...............any ideas.

The spark is hot, the timeing looks good, the carb..........well, ii took it aprt and went through it several times. It looks good. Float seems a little high maybe...Hmmm..maybe readjust it a little. Dont know of what could go wrong with a rotary valve.........


Damn my right leg is sore!!!!!! LOL!

 

ha ha ha ha... It's been a long time since I had a sore leg from one of those...lol. You do learn to use your left leg after a while.

You said you reused the old head gasket? I would have to lean towards that. If timing is on, carb is clean, and good spark, the only thing left is compression, right.

Check your compression....I bet that old head gasket is done.

 

I checked the compression on the ol gal, she was showing 110 psi, I am sure it is higher when running. Kickstarting it can only go so far! The head gasket is copper, and come off in good shape, it has no leaks thankfully. The piston and rings lokked good as did the cylinder wall, but like an idiot i didnt mic the piston or cylinder! oh well.

This ol thing still cant fire off wirth a damn. I tore down the carb last night and double checked the float position, for clogs in the jets, etc....nothing out of the ordinanry. However, upon reassembly i found one thing of interest, the main jet that screws into the bottom of the guide for the main needle, it moves! The whole assembly moves within the body of the carburator! about .125" or less. When I disassembled the carb, I didnt lose anything. Is this normal for this mikuni carb?

I know i need to get the book! Just dont have the extra cash right now. If noone knows, IS there a link to site that might have the exploded view of the carburator? Realy want to get this bike going!

thanks

 

110 psi?

 

Ya, 110 psi.......something wrong?

 

http://www.kawasaki.com/Scripts/ImgS...F=P&ilRE=8

http://www.kawasaki.com/DefaultFrame...OSEVEHICLE.ASP