Author Topic: K1 Sohc750 It's alive! But I need some assistance  (Read 1633 times)

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Offline 750four

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K1 Sohc750 It's alive! But I need some assistance
« on: May 22, 2011, 10:11:14 AM »
Fired my 750 for the first time today. I bought it 2summers ago dead to the world. Pulled the engine and rebuilt the head with ape springs, light portingand a valve lapping. New gaskets too.
parts I invested in:

Dyna s ignition
Dyna green coils
Cycle x carb system (dual mikunis)
New 12v battery
All new wiring
Old mac drags minus the baffles and about 6" of pipe

And I also clean the engine and paimted the bottom end black amd sand blasted the head , polished the valve cover. If that matters to any one.


So it fired up after it was primed with gas. Starts first kick and sounds like a beast!

Offline 750four

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Re: K1 Sohc750 It's alive! But I need some assistance
« Reply #1 on: May 22, 2011, 10:19:53 AM »
Now for a couple of questions

I have a leak from the alternator cover. Is it an oil seal on the crank shaft or is it the cover. Not sure oils supposed to be in there?

My clutch seems to not be ingaging aswell. But I also havent had a chain on it yet. When I put it in gear, engine off, I noticed if I pull the clutch it still acts like it is in gear. I did have the cover and pully arm off when painting. Also bought and installed new lever and cable.

My mikunis are very close seem to be jetted correctly, but I wonder if there was a starting point for the air adjustment screw. I'm at about 5 turns out and thats after turning them in a bit.

Online CycleRanger

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Re: K1 Sohc750 It's alive! But I need some assistance
« Reply #2 on: May 22, 2011, 10:59:13 AM »
Yes, the alternator housing is full of oil, as it should be.
You should probably replace all the case gaskets, alternator, clutch, oil pan etc.

If the engine was sitting for an extended period of time the clutch may indeed be stuck.
If may free up on its own after you run the engine a bit and circulate the hot oil or you may have to put the chain on it and rock the bike back and forth with it in gear while engaging the clutch to unstick the clutch.

If the clutch won't un stick you'll have to pull it and probably replace the plates.

Do you have a copy of the Honda Shop Manual or Parts List for your bike? Get one here:
https://www.honda4fun.com/materiale/documentazione-tecnica
CB750K5        '79 XL250s     CL350K3
CB750K3        '76 XS650      '76 CJ360T

Offline Johnie

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Re: K1 Sohc750 It's alive! But I need some assistance
« Reply #3 on: May 22, 2011, 02:33:17 PM »
Keep in mind an oil leak from the left side engine cover could also be the rubber grommet where the stator wires exit the cover on the back side. Been there done that...good luck with it.
1970 CB750K0 - Candy Ruby Red
1973 CB750K3 - Candy Bacchus Olive or Sunflake Orange
1970 Chevy Chevelle SS396 - Cortez Silver
1976 GL1000 Sulphur Yellow

Oshkosh, WI  USA

Offline 750four

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Re: K1 Sohc750 It's alive! But I need some assistance
« Reply #4 on: May 22, 2011, 03:59:25 PM »
Thanks for the reply's guys. I was thinking the worst and prepping for a mess of a main oil seal replacement. I'm thinking that the clutch may have worked before I pulled it all apart.

I need to put a chain on it and run it for a bit maybe rock it back and forth a bit in gear.

I had put a set of the aftermarket finned side covers on and I think the left side was a bit cattywompie.

So thats good news, I may just cut a good thicker rubber gasket out at work. I replaced the rest of the gaskets for the covers.
That left cover just didn't seem to sit right though

Offline 750four

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Re: K1 Sohc750 It's alive! But I need some assistance
« Reply #5 on: May 22, 2011, 04:01:33 PM »
wanna hear it run??:  :o

right after kicking it, starts 1st kick. Haven't timed it or had time to give it a proper tweaking. So I'm being nice here.

SOHC cb750 bomber first fire