engine 1981 650c

If it's broken or just needs tweaked

Moderators: Volker_P, tidd650

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holysmokes
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Joined: Tue Apr 17, 2007 7:03 pm
Location: nova scotia

engine 1981 650c

Postby holysmokes » Mon Apr 30, 2007 1:35 pm

got this bike in a bunch of boxes, finally found a rear tensioner, front guide

these are a few pictures, Ill use this new topic as a home base for my confusions

Ive had many dohcs apart, this'll be my first 650 sohc

if its true ..ignorance is bliss, Im gonna be real happy like






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Vatch
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Location: West Virginia, USA

Postby Vatch » Tue May 01, 2007 8:51 pm

I love the shot of your garage, random front fork and wheel in the back ground. I'm guessing if you've worked on DOHC, a SOHC should not be much different, maybe a little simpler.
'99 1500 Drifter

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holysmokes
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Location: nova scotia

Postby holysmokes » Tue May 01, 2007 9:30 pm

well. Im used to the starter clutch being on the left end of the crank. easy to change

charging rotor on the right[which by the way is the same as the 750 dohc , checked out at 4.4 ohms}

pulsers on the left[checked out as 506 more or less, been a few days :lol: ]

Im gonna rering this engine, hone and install

my 750 dohc pistons are a bit too big, but if i had the extra funds, they would be in there;;they have new rings on already

I think the wrist pin looks identical :?

the rest of my shop is filled with dohcs , in banana boxes

3-4 bikes worth, got this bike on a trade for my 750custom + cash :idea:

alot of other parts are interchangeable..controls, gauges cables, wheels etc etc

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holysmokes
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Joined: Tue Apr 17, 2007 7:03 pm
Location: nova scotia

Postby holysmokes » Wed May 02, 2007 1:48 pm

Ive got the cases stuck together, oil pump in,


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Chris
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Postby Chris » Thu May 03, 2007 1:16 am

Man, I hope my case is that clean inside.
1980 CB650c

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holysmokes
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Postby holysmokes » Wed May 09, 2007 5:11 pm

cylinders honed


new rings in, standard size

next rebuild the head and relap the valves




Image

Pinhead
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Postby Pinhead » Wed May 09, 2007 5:22 pm

Are your replacement rings moly coated? It reduces friction and makes everything last a lot longer.

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holysmokes
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Postby holysmokes » Wed May 09, 2007 5:25 pm

I bought regular honda rings, oiled them up good. slid em in

$30 a hole

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Volker_P
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Postby Volker_P » Thu May 10, 2007 1:05 am

Good to see it is coming together.
One curious question: did you get the cam chain tensioner in after fixing the cylinders or more or less simultaneously?

I guess moly is molybdenum?

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holysmokes
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Location: nova scotia

Postby holysmokes » Thu May 10, 2007 6:51 am

front guide goes in just before the head is lowered

the rear tensioner goes in after the head is down

my dohc engines have cylinder studs in the way , when lowering the cylinders, these engines are stud free, which is very thoughtful of honda

this is the basic reason the dohcs cannot have the head removed in -frame

moly is the molybendum

Pinhead
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Joined: Thu Jan 04, 2007 2:26 am

Postby Pinhead » Thu May 10, 2007 12:56 pm

Volker_P wrote:I guess moly is molybdenum?


Yeah.

"Moly rings, free power (and mpg) for older engines?"

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holysmokes
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Postby holysmokes » Thu May 10, 2007 1:58 pm

Image



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after relap

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holysmokes
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Postby holysmokes » Mon May 14, 2007 12:42 pm

got the old bird running

engine partially bolted in, til its 100%. i never do a final bolt in til Im sure of my destination :roll:

these engines are quite light. I lifted it in, quite easily. hell of a lot lighter than those 750 dohcs, about 30lbs difference




sorry , wrong picture :wink:
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need to readjust my valve clearances, and do some fine tuning on the carbs



the elton johnish yellow maybe too gay, I may go a nice black and do a red trim




Image

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Vatch
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Location: West Virginia, USA

Postby Vatch » Mon May 14, 2007 6:18 pm

holysmokes wrote:sorry , wrong picture :wink:


the elton johnish yellow maybe too gay, I may go a nice black and do a red trim


Hey, if you're going to post a picture of a giant rack have the decency to post a clear picture :lol:

You could always tone down the yellow to say school bus yellow. At least they will see you coming.
'99 1500 Drifter

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holysmokes
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Joined: Tue Apr 17, 2007 7:03 pm
Location: nova scotia

Postby holysmokes » Mon May 14, 2007 7:01 pm

rack, that aint no rack, thats the whole closet :lol:


someones gonna get their eyes poked out. , if they aint careful :wink:




Im gonna paint my header pipes caliper paint red

leave the cannister black

go to a nice black mettalic

add some red tank trim, around the edges

red calipers

use some red paint on my emblems for an accent


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