Author Topic: Clutch issue 78 750 F.  (Read 416 times)

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Offline 754

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Clutch issue 78 750 F.
« on: August 18, 2018, 10:11:28 AM »
 Just installed a rebuilt 78 F  motor into my 74.
 When I first rode it , put it in gear and it UUuurkkked and stalled.... on or off. Felt like a Barnett racing clutch.. , had to slip it or stall.
 Next day rode to town  6 miles all fine, then it sat 2 hours. When I got on it to ride home clutch was easily slipping.... babied it home.
 Checked the clutch, at locknut, no freeplay. Reset it,gave it a bit of clearances locked the nut.
Now it felt more like a normal clutch with  stronger springs.
 Yesterday I ride, put on about 10 miles  park it,  for 7 hours. Started it up and ran it a few minutes during that time m but did not put it in gear.
 Went to leave, same slipping problem..

 Now I can see it may ge running in a bit and needing an adjustment once, but this has me stumped.
 Any ideas or anyone had this happen? Very strange...
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline jgger

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Re: Clutch issue 78 750 F.
« Reply #1 on: August 18, 2018, 10:52:31 AM »
Just a thought Frank, but could the end be getting ready to pull off the cable?
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline scottly

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Re: Clutch issue 78 750 F.
« Reply #2 on: August 18, 2018, 11:42:04 AM »
Lifter plate bolts backing off?
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline 754

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Re: Clutch issue 78 750 F.
« Reply #3 on: August 18, 2018, 11:55:47 AM »
I have had an ear break in use, made it slip as you made it work hard, higher revs.  This slips at every RpM
 Have not checked  yet , but the first time the locknut adjustment on the motor  had gone to zero freeplay.

 If the cable were pulling out of the end  free play would Increase , but clutch would still work.
 
 I finally looked at a manual , it said back off screw 1/4 to 1/2 turn then tighten locknut.
Which I did today, will test later. When I adjusted the other say I barely backed it off. 
« Last Edit: August 18, 2018, 01:42:32 PM by 754 »
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline seanbarney41

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Re: Clutch issue 78 750 F.
« Reply #4 on: August 18, 2018, 12:06:52 PM »
Frank, do the complete clutch adjustment, not jus the cable, before panicing. 
If it works good, it looks good...

Offline 754

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Re: Clutch issue 78 750 F.
« Reply #5 on: August 18, 2018, 01:45:09 PM »
I added above, re adjusted lockscrew today.
 And this is important, left the cover off.   That may do it. First time  I put cover back on m that usually means you got to go in again.,
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Clutch issue 78 750 F.
« Reply #6 on: August 18, 2018, 05:57:35 PM »
Take a peek at the guts and make sure it has all the ingredients of the late model clutch. This clutch thing gets iffy when people start playing/mixing/matching/replacing with the guts.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)