Topic: 1980 CB650C... stumped

[ZakDanger]

Getting very very discouraged. She didn't run that well when I got her, needed to change out my top to bottom end gasket, she was leaking oil real bad. Got that done, and in the process stripped 4 bolts in my head. Retapped, new screws, put back together.

Turn it over, choppy idle, just as I start messing with the air mixture screws I hear a "ka-chunk" and some very very bad noises coming from the cam chain.

Sure as hell I pull the top off and my cam chain sprocket had somehow forced the bolts out of itself and lodged quite awkwardly in the top end and the camshaft. :sigh:

Break er all down back to the bottom, fish out the sprocket screw I was missing, buy some new ones off Bike Bandit cuz they're stripped, throw them back in with some loctite. (turns out I screwed up when I re tightened the tensioner)

In the meantime I check my carbs again, and one of my float needles is stuck. No wonder she idles awful.

OK! Put it all back together, CAREFULLY this time. Follow everything to the letter from my book, which is what I should've done the first time instead of rushing.  Rookie mistakes are usually made by rookies right? Never again.

Fire it up last night and... not good. Bad idle, won't stay without the choke. Only two of my pipes are hot. 1 and 2. Check my spark on 4 and 3, firing, check my drains in those carbs for fuel, plenty. Check my plugs on 4 and 3, they're wet. So... wtf?  This is the first bike I've ever worked on and goddamn if I'm not ready to just cut my losses and take it to a shop.  But before then, I have to exhaust (no pun intended) every avenue at my disposal. I put this to you with a question... Compression??

[Blueridgerunner]

I hope I'm wrong here, but could've bent valve or damaged piston when cam chain messed up? You could do a compression check to see.  Putting things simply, you need fuel/air, ignition and compression. Seems like you have checked the first two. Good luck.

[chickenman_26]

This is the first bike I've ever worked on

No S**t?

...and goddamn if I'm not ready to just cut my losses and take it to a shop.

Where I believe you'll find that your tinkering has ruined more parts than you're aware of.

  But before then, I have to exhaust (no pun intended) every avenue at my disposal. I put this to you with a question... Compression??

Look - no disrespect intended, but you're not a rookie. You're a one-man disaster area - over tightening bolts till they strip, and leaving cam sprocket bolts so loose that they back out. If you exhaust any more avenues, you could succeed in destroying the top end, if you haven't done that already. Maybe you bent some valves as ridgerunner suggests. Or, your carbs could be fouled up and flooding #3 and 4. But if you "repair" them as well as you did the top end, I wouldn't expect the bike to even start.

I don't know why some first timers think these bikes are no more complicated to repair than a pencil sharpener and end up turning their bikes into hamburger, but it happens all the time. A DIY repair to save money ends up tripling the repair costs, or the bike gets sold for parts or goes to the scrap yard. I think Clint Eastwood said it best - A man's got to know his limitations. Take your bike to a mechanic.

Stu

[bollingball]

The cyl. don't add up. Are your plug wires on the correct cyls.?

[ZakDanger]

Hey Stu, don't hold back man, let me know how you really feel!

I actually got the bike for real cheap to work on while I took my motorcycle technician courses. I work on my bike in a garage with about 5 other guys, 2 are car mechanics, one is a bike mechanic. Most of the time they shake their heads at me, but everyone has been unbelievably helpful.

The bike was a piece of junk when I got it, and if it ends up being a piece of junk when I'm done, but I learned something then I consider it a success.

[ZakDanger]

boilingball - yes they are 1/2/4/3 according to spec

[bollingball]

Make sure Cly. #1are being fed from the same coil and that coil has the blue wire from the points. Then check Cly. #2 & #3  from the other coil that has the yellow wire from the points. For 4 and 3 not getting hot but firing and has gas still makes me think you have the plug wires mixed up. What you stated was firing order that does not mean you have them on correctly

[chickenman_26]

Hey Stu, don't hold back man, let me know how you really feel! I actually got the bike for real cheap to work on while I took my motorcycle technician courses. ... but I learned something then I consider it a success.

Like I said Zak - no disrespect intended. So you've taken bike technician classes? You may want to review the part about service literature and torque wrenches  Seriously though, When you fook up something, that's learning the hard (and expensive) way, provided some actual learning occurred. Reading and asking your buds there in the shop before you tackle a job like that might give better results the first time.  Just saying....

BTW, I agree with bollingball. Check the plug wiring - common mistake.

Stu