Author Topic: CB750 Barn find project - First Timer  (Read 53214 times)

Offline Green1

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Re: CB750 Barn find project - First Timer
« Reply #435 on: July 21, 2018, 09:20:49 PM »
Turns out that throttle cable guide bracket thing is soft and can be bent by hand so it’s bent back into the proper position now

Now you mention it its clear its bent in your pic.
Somehow I didn't see that before
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Offline Underdog1

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Re: CB750 Barn find project - First Timer
« Reply #436 on: July 21, 2018, 09:48:55 PM »
Turns out that throttle cable guide bracket thing is soft and can be bent by hand so it’s bent back into the proper position now

Now you mention it its clear its bent in your pic.
Somehow I didn't see that before

Yeah I didn’t even notice when I was scratching my head about it being out of whack earlier!

Offline Underdog1

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Re: CB750 Barn find project - First Timer
« Reply #437 on: July 22, 2018, 01:45:34 PM »
Quick go on the seat today. Instead of using trim strips around the seatpan to stop the cover wearing throughbo glued some vinyl material. Roughly shaped the foam with a bread knife, hard to neatly cut recon foam as it turns out! Have left the foam slightly oversized for now as it’s being covered by a friend who is a pro so he can probably trim it back a bit nearer than what I can.







Offline Underdog1

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Re: CB750 Barn find project - First Timer
« Reply #438 on: July 22, 2018, 07:53:53 PM »
not wanting to get into anything serious with the bike today I’ve made up the 4 into 1 exhaust. The reverse cone is 12 inches long and was 0.7mm too small to slide over the collector (according to my micrometer!). Cut a slit in it, lubed it up with copper slip and banged it on with a rubber mallet. The bracket is just for show as it won’t be coming off again without a fight!

« Last Edit: July 22, 2018, 08:06:44 PM by Underdog1 »

Offline Rob62

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Re: CB750 Barn find project - First Timer
« Reply #439 on: July 22, 2018, 09:23:44 PM »
Any baffles in there ?  :D

Looks nice, is it a good fit onto the cyl head? The headers and collector look nicely formed, what make is it, or is it made up from various pipes?

Offline Underdog1

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Re: CB750 Barn find project - First Timer
« Reply #440 on: July 22, 2018, 10:28:10 PM »
Any baffles in there ?  :D

Looks nice, is it a good fit onto the cyl head? The headers and collector look nicely formed, what make is it, or is it made up from various pipes?

It has a stainless steel perforated core but it’s pretty open.



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Offline Underdog1

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Re: CB750 Barn find project - First Timer
« Reply #441 on: July 23, 2018, 10:42:10 AM »
Been thinking about the breather hose that comes from the back of the cylinder head thismorning, originally it connected to the air box but now that’s gone I need another solution.

I could just route it down to the ground so anything coming out of it would go overboard - but on a well running bike should anything be coming out of it outside of vapour? You can get fancy little filters to go on the end of the breathe hose which you can attach anywhere but in my head I’m imagining it becoming sodden with oil over time and causing a mess?

Offline Bryanj

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Re: CB750 Barn find project - First Timer
« Reply #442 on: July 23, 2018, 10:51:19 AM »
There should only be vapour coming out, unless you have a problem. The 500 does just exit to atmosphere just in front of the rear wheel

Offline Underdog1

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Re: CB750 Barn find project - First Timer
« Reply #443 on: July 25, 2018, 09:20:10 PM »
There should only be vapour coming out, unless you have a problem. The 500 does just exit to atmosphere just in front of the rear wheel

Nice one bud.

Anyone know where I can get a shorter speedo cable from? I’m not using the front fender (will use a brace) so It’s now got a lot of slack where it loops backwards, ideally I’ll just run it up the inside of the fork lower instead so could do with it being 20-30cm shorter

Offline Bryanj

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Re: CB750 Barn find project - First Timer
« Reply #444 on: July 26, 2018, 02:06:20 AM »
Dont know anybody who makes custom speedo cables, used to find longer ones in the US for the chopper boys but never seen shorter. Perhaps a different Honda bike might fit?

Offline petermigreen

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Re: CB750 Barn find project - First Timer
« Reply #445 on: July 26, 2018, 08:15:28 AM »
Think venhill will make cables to specification.


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Offline Underdog1

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Re: CB750 Barn find project - First Timer
« Reply #446 on: August 06, 2018, 06:15:19 PM »
Took the old girl up to see bryanj on Saturday who helped me with the wiring


 
He also knocked me up some braided hoses for the front end.

Today I’ve fitted the chain, plumbed in the oil tank, fitted the exhaust,  prepped the oil pump by submerging it in oil and turning it back and forth until no air bubbles come out.

Filled her up with oil and have been kicking her over with the killswitch on to try and get the oil pressure light to go out. After 60 or so kicks no luck yet.

The kickstart seems to have a limited range of movement and it’s not springing back up. Could this be due to dry internals? Hopefully it isn’t anything assembled incorrectly!

This pic shows the end of the range on the Kickstart.




Offline philward

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Re: CB750 Barn find project - First Timer
« Reply #447 on: August 06, 2018, 08:28:13 PM »
Try the packing the oil pump with vaseline trick that many members recommend. I used it for the first time on the CR and oil light was out in no time (with plugs out for ease on the old legs!)
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Offline Rob62

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Re: CB750 Barn find project - First Timer
« Reply #448 on: August 06, 2018, 09:01:17 PM »
If you spin the engine on the starter the oil light should go out fairly quickly. I didnt have any trouble with the oil pump on mine, i took it out and changed the gauze but didn’t strip it completely. I never primed it, just refitted, filled up with oil and kicked her over until oil appeared at the rockers...

Offline Nurse Julie

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Re: CB750 Barn find project - First Timer
« Reply #449 on: August 06, 2018, 09:22:59 PM »
Never spin a newly rebuilt engine on the button, the button pusher tends to get carried away and if the oil isn't pumping around the engine it will seize very quickly.
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