Mech quit on me.

If it's broken or just needs tweaked

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juntjoo
Posts: 247
Joined: Fri Nov 10, 2017 6:19 pm

Mech quit on me.

Postby juntjoo » Thu May 10, 2018 11:06 am

They mostly do Harleys so he's not confident, gave me other excuses but that's basically it. A bit ago I somehow ended up with zero compression in #1 after adjusting my valve clearances so I must have bent a valve or something. All I know is that it was running great on all four except for a little clacking I'd had from the get go, so I decided to back in and adjust my clearances again and do it by the book exactly and double check each tappet after tightening and using the correct torque and after all was said and done to a T suddenly I was without compression on #1. So I can only assume I need to get into the head, something I'm unfamiliar with.

So I did take everything off down to the head which is loosened and ready to be removed, when mechanic, after weeks of procrastinating with towing my bike over decided they couldn't do it. Cool, I don't blame em plus I wouldn't want anyone not comfortable working on it work in on then charging me per their education.

So I could totally get into it and buy the necessary tools and learn myself some valves but I really should not at this time in my life atm. Should I try to see if I could get the Harley guys to take my head and just redo my valves, no guarantees? I'm sure he won't be able to guarantee anything just taking the head. Or maybe take it to this car mechanic I know who seems much more willing to do different work as he's a custom worker mechanic/machine shop and knows heads in general. Shouldn't be too crazy for a general mechanic no? Or are our heads something different or tricky? Also, getting it back in, I'm guessing maybe a bit more involved getting it back up? I think I want to try this custom guy before my local Harley mech actually.

What do you guys think?
82" cb650 Nighthawk

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Folsoml
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Re: Mech quit on me.

Postby Folsoml » Thu May 10, 2018 8:30 pm

My feeling has always been that you should never buy a 30+ year old vehicle if you do not intend to work on it yourself. If you pay someone else to do it, you will quickly spend more than you paid for the bike to start with.
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juntjoo
Posts: 247
Joined: Fri Nov 10, 2017 6:19 pm

Re: Mech quit on me.

Postby juntjoo » Thu May 10, 2018 9:05 pm

Folsoml wrote:My feeling has always been that you should never buy a 30+ year old vehicle if you do not intend to work on it yourself. If you pay someone else to do it, you will quickly spend more than you paid for the bike to start with.


Jesus!
82" cb650 Nighthawk

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Folsoml
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Joined: Sat Apr 07, 2012 9:02 pm
Location: North Florida

Re: Mech quit on me.

Postby Folsoml » Fri May 11, 2018 8:17 am

Yeah, even when you get them running right, they just need CONSTANT maintenance.
Have a problem with your CB650? Have a technical question? Click here!


My Current Bikes: 2005 HD FLHTCUI Electra Glide Ultra Classic, 2007 Yamaha Vino,

juntjoo
Posts: 247
Joined: Fri Nov 10, 2017 6:19 pm

Re: Mech quit on me.

Postby juntjoo » Fri May 11, 2018 12:01 pm

Folsoml wrote:Yeah, even when you get them running right, they just need CONSTANT maintenance.


Why didn't you guys tell me this before!? You just saw me walk in all doe eyed blissful about my new used first bike ever and didn't want to ruin it for me. Plus it's much more fun to watch me figure it out in my own lol. Thanks.

So I talked to my regular 4 wheel vehicle mechanic and he's willing to work on my head, and it seems easy (enough) to put it back up. Clymer says it's just reverse of steps to remove. I have no idea, at least I haven't yet tried to imagine with my knowledge of valve components, how they align when putting the head back on, if I need to do something or it aligns automatically but I just read that one step in the Clymer which doesn't indicate any manual aligning, so, well I guess I'll find out. But since I'm down in here, should I do anything with the pistons? I had fine compression before this all happened presumably with my valves, as most everyone who checked my compression readings agreed, so I'd like to take that as my pistons and cylinders are in good health. Maybe it goes that if you go this deep you should have a min of a variety of calipers to check measurements? Excuse me. I don't even know what I should be asking. How about I just don't touch it?
82" cb650 Nighthawk

juntjoo
Posts: 247
Joined: Fri Nov 10, 2017 6:19 pm

Cylinder head off. What should I do while down here?

Postby juntjoo » Fri May 11, 2018 4:31 pm

82" cb650 Nighthawk

juntjoo
Posts: 247
Joined: Fri Nov 10, 2017 6:19 pm

Re: Mech quit on me.

Postby juntjoo » Fri May 11, 2018 4:35 pm

What do you think for an engine with 7k miles? And for a valve to cause zero compression would it be more obvious? I felt a slight slight raise, maybe I imagined it, on exhaust #1.
82" cb650 Nighthawk

juntjoo
Posts: 247
Joined: Fri Nov 10, 2017 6:19 pm

Re: Mech quit on me.

Postby juntjoo » Mon May 14, 2018 10:34 pm

So I dropped my head off with my general mechanic/ machine shop guy and right away after explaining how or was fine til I did my valve clearance adjustments he's sure I over tightened the #1 one causing the no compression there but i don't know I'm convinced as I triple checked my adjustments that last time, so we'll see i guess. He's gonna check it out deeper but just looking at it when I brought it in he didn't see anything obviously bent. I also brought him the cover(with tappets) so he could bolt it on to see how it all fits together. I didn't loosen the tappets removing the cover so the cover and head should match up just as they did before taking it apart. So, he'll check everything is in spec and if he doesn't find anything to replace (valve) then I'll just put it back together or maybe have him do it but if my head is fine and I just messed up on the adjustments I will want to know what I did wrong so i don't do it in the future. I'm just baffled by the idea I over tightened it. Anyone ever over tighten a tappet down causing loss of compression? Anyway, I'll report back...
82" cb650 Nighthawk


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