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stevanjohnson
03-23-2010, 11:24 PM
i think my 1970 cb350 bit the dust tonight....

i was riding it home from work and all of a sudden it died, i threw it on reserve fuel a few miles before that because i needed to make it to a gas station all of a sudden bam..it was done. i thought "g'damnit im a retard...i need gas." called a friend, had him come fill me up, took it a long time to kick over, finally kicked it over, went to take off and it died. made a weird noise and died...then i tried to kick it over again and the kick start wont budge. completely stuck up top. went back home, grabbed a spark plug wrench and WD-40, tried to take the plugs out and free it up (thought maybe it was vapor locked?) still no go...only guess is its completely seized up and needs a rebuild. any guesses? not hyped...especially since i was going to sell it next weekend to some kid because i was about to upgrade.

typical..

mad750
03-23-2010, 11:45 PM
Yup, time to open it up.

revmike
03-24-2010, 12:17 AM
Good news is it might be something with the tranny like a busted pawl/shifting fork. Bad news is you gotta tear it all the way down to get there. Can you work the shifter? Can you shift it into neutral? If there seems to be some shifting issues, maybe it's the tranny (obviously). Last one I did had a busted pawl and one scored gear, otherwise it was spotless. Cost about 12 dollars in parts but millions of hours of work and spent expletives...

~Rev Mike

shop102
03-24-2010, 5:00 AM
hey dude. i used to race 350's and have been elbow deep in them more that a few times. the cam chain tensioners SUCK in 350's of all years. they are two hard rubber wheels that fail. thats where my money is. it is VERY easy to tear the top end down on these. let me know if you need any help



also get one of these and you will never have to worry about it again http://bore-tech.com/catalog/camchaintensioner-p-41.html

revmike
03-24-2010, 4:47 PM
I was thinking tensioner too, but I've never had one fail completely so I dunno. I picked up one of those cool tensioners years ago as well.

If you end up needing any parts, put it up here, or PM me. I have a lot of used 350 stuff, esp if you just wanna fix it to sell it...

~Rev Mike

eric123
03-24-2010, 7:33 PM
Lift the bike up and put it in gear...See if you can rotate the tire...Hopefully she isn't seized...

stevanjohnson
03-24-2010, 9:31 PM
thanks for all the suggestions guys it makes me feel a little less stressed out. got the bike home this morning, when its up on the center stand i can put it in neutral and go thru the gears and spin the tire and everything....so not really sure it means yet..been busy with work all day

shop102
03-24-2010, 9:43 PM
I was thinking tensioner too, but I've never had one fail completely so I dunno. I picked up one of those cool tensioners years ago as well.

If you end up needing any parts, put it up here, or PM me. I have a lot of used 350 stuff, esp if you just wanna fix it to sell it...

~Rev Mike

ditto on that. i have a bunch of 350 stuff as well. that tensioner probally bit the dust, your chain jumped on the cam gear and your piston smacked into the valve. im speaking from experience on this one

MIKE47
03-25-2010, 6:58 AM
Tensioner would be my first guess. It probably shit and jumped time. I'm sure if it did you at least bent a valve, if not broke one right off. Tensioners are pricey (about $150 new). Can't remember the guys name but it's Todd ...something racing that makes a slipper type tensioner. It was a bit cheaper than a NOS one. Read the manual carefully to do the timing, it can be a bit confusing. And make sure you turn it by hand slowly before you jump on the kicker when done. If it's a tooth off it'll bend a valve again. If the valves look ok clean the head and fill the chamber with water or even better gas or alcohol and let it sit upside down for a while. This will let any liquid leak past the seats if you have a bent valve.

revmike
03-26-2010, 5:36 PM
Todd Henning? I think that's where I got my stuff too.

Check here....

THR cb350k4 (http://web.me.com/thracing/THR/CB350_K4.html)

MIKE47
03-26-2010, 7:56 PM
Todd Henning? I think that's where I got my stuff too.

Check here....

THR cb350k4 (http://web.me.com/thracing/THR/CB350_K4.html)

That's it.