Author Topic: 1978 CB750K skill builder (read: low budget)  (Read 25195 times)

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Offline wayfastwil@yahoo.com

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #175 on: February 11, 2019, 07:06:22 am »
Looking for tank and seat ideas for a 1978 CB 750 I don’t care for the 1978 OEM stuf. I’d like to go with CB 1976 tank and seat thanks wil

Offline slikwilli420

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #176 on: February 11, 2019, 09:37:51 am »
Put the baffle back in. You might find that the proper back pressure does wonders. I run the baffle in my MGPW pipe, without the wool in there on my race bike. The open exhaust is annoyingly noisy and counterproductive.
All you gotta do is do what you gotta do.

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Offline SOHC4 Cafe Racer Fan

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #177 on: February 11, 2019, 10:06:00 am »
Looking for tank and seat ideas for a 1978 CB 750 I don’t care for the 1978 OEM stuf. I’d like to go with CB 1976 tank and seat thanks wil

Any 1975-78 CB750F Super Sport tank. Bargains are still out there but you need to hunt.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
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Offline PeWe

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #178 on: February 11, 2019, 12:56:16 pm »
Put the baffle back in. You might find that the proper back pressure does wonders. I run the baffle in my MGPW pipe, without the wool in there on my race bike. The open exhaust is annoyingly noisy and counterproductive.
+1
I have found that a too open pipe will cause bad an uneven low rpm response. Cruising in town work better with more back pressure.
CB750 K6-76 1005cc JMR Billet block.
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline Davez134

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #179 on: February 12, 2019, 02:50:37 pm »
Put the baffle back in. You might find that the proper back pressure does wonders. I run the baffle in my MGPW pipe, without the wool in there on my race bike. The open exhaust is annoyingly noisy and counterproductive.
Ok, I will try that. It came to me without a baffle, so I’ll have to find one that will fit.

Offline Davez134

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #180 on: June 11, 2019, 06:42:17 pm »
I know its been a while. I have been busy with a lot of other projects, but I didn't want to leave this unfinished. I put a baffle in the exhaust, and it sounds/runs better. I believe the hard starting issue was related to the ignition...
After I cleaned out the tank and carbs again, it started up better and the baffle seemed to help as well. I gave it back to him, but he called me once again. He was riding, and it just died, would not start again. I went over to his house to start one system at a time, Checked fuel delivery and it seemed fine. next I went to check compression and valve clearance. Thats when I found the problem. When I took the points cover off to use the timing marks to check the valves, I noticed the nut on the end of the advance shaft was loose! It had enough play to let the advance unit slip out of the keyway and it stopped spinning. Tightened, cleaned the threads, new nut, and some loctite. Runs amazing now!

Offline calj737

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #181 on: June 12, 2019, 01:24:19 am »
Its always the simple things that get overlooked in a large project. One single nut makes all the difference  :D Glad you got it sorted out for him, I bet he's pleased as punch with it now.
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Offline Stev-o

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Re: 1978 CB750K skill builder (read: low budget)
« Reply #182 on: June 13, 2019, 02:44:45 pm »
Thats a new one for me!   Thx for closing this out.

What ya working on now?
'74 "Big Bang" Honda 750K [836].....'71 Honda 750K project.....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........