Author Topic: CB750K4 New project  (Read 5969 times)

Offline Woodside

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Re: CB750K4 New project
« Reply #30 on: October 19, 2017, 05:37:58 PM »
i have absolutely no idea what make mine was i always thought it may have been american....it had a slightly longer seat which is why we were always 2's up....
i think it had a twin oval top tube too...
just spent half an hour looking at pics on net but nothing even close...
« Last Edit: October 19, 2017, 05:56:49 PM by Woodside »

Online K2-K6

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Re: CB750K4 New project
« Reply #31 on: October 19, 2017, 06:10:11 PM »
Think my first bike came from Bracknell amenity recycling center, as it's now known, aka the tip but I was too exited to get out on it to wonder where it came from I guess.

We also grew up initially believing that Frencham little pond was the seaside,  local joke for anyone in that vicinity.

Online K2-K6

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Re: CB750K4 New project
« Reply #32 on: October 19, 2017, 06:24:24 PM »
Not something like these?

https://thecabe.com/forum/threads/schwinn-dx-i-think.104231/

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Offline Woodside

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Re: CB750K4 New project
« Reply #33 on: October 19, 2017, 06:33:10 PM »
nope it was more bmx'y
i will look again later..
i used to ride it to frensham...its about 3 miles from home....
« Last Edit: October 19, 2017, 07:12:50 PM by Woodside »

Offline Rob62

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Re: CB750K4 New project
« Reply #34 on: October 19, 2017, 07:33:06 PM »
Those american “muscle bikes” are real nice but quite expensive by the time you pay for shipping... I almost brought a schwinn stingray over from delaware a couple of years ago but it was gonna cost north of £800 so i settled for a uk bike instead.... a vindec same as the one i had as a lad

Some nice photos here
http://www.nemusclebikes.com/bicycles.php

My push irons








Looks like I’ve hijacked my own thread here... I’ll have to start another once i get fettling the 750


« Last Edit: May 01, 2018, 06:11:54 PM by Rob62 »

Offline AshimotoK0

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Re: CB750K4 New project
« Reply #35 on: October 19, 2017, 07:50:10 PM »
Missus had a Moulton once but gave it away

DS has this for sale at the mo'  :)


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Offline Rob62

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Re: CB750K4 New project
« Reply #36 on: October 19, 2017, 08:05:26 PM »
Very cool..... i like the CBX behind it, i had a look at it when i was there... must be a contender for the ultimate classic jap bike... if only i had a big garage, and some more money  :-\

Offline Rob62

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Re: CB750K4 New project
« Reply #37 on: December 31, 2017, 05:59:31 PM »
Well, I finally started working on the 750 today.. xmas out of the way and decorating finished so no more excuses. Didn’t do a great deal, tank and seat off. Tank is in great condition just a few scratches here n there so will stay as it is. Seat is a brand new replica and tbh looks great, just missing the honda logo but i can stencil that on later if i feel the need. I want to change the usa bars for some lower uk style ones so off with those. Took me half an hour to get the wires out of the bars as the sheath had hardened, will replace it with heat shrink. Stripped off the headlight and separated the various wiring bundles. I’ll draw up a diagram later to make it easy for myself at rebuild time. One or two wiring mods in there, not too bad though. Everything came apart easily and looks to be in great condition. I lifted the rubbers off the carb tops for a look, one of the rubbers is split but the other three are ok, there is still yellow paint on top of the carb slider adjusters...!. Noticed another wasps nest between the rear frame and the plastic mudguard. Brought some parts inside for a clean up but thats all they will need i reckon, switches and master cylinder...  Hopefully will be a painless recommission...




« Last Edit: May 01, 2018, 06:12:57 PM by Rob62 »

Offline Rob62

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Re: CB750K4 New project
« Reply #38 on: January 05, 2018, 09:26:09 PM »
Done a bit of cleaning in the week, headlamp is the original sealed beam, still works so cleaned it up, virtually zero rust on the rim, probably half a candle power but is original so will stay for the time being.


The switch gear cleaned up easiily, just needs re sleeving where the old stuff disintegrated.


The master cylinder needs a new diaphragm as the old one has hardened and shattered, the cap is like new, but worst of all the circlip is stubbornly rusted in despite a soaking with penetrating oil. Will have another go at it this weekend as I like the patina and really want to keep it on the bike.

The mirrors are good except for some heavy pitting on the stems, but they look original so I will keep them for the time being.


« Last Edit: May 01, 2018, 06:14:08 PM by Rob62 »

Offline Rob62

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Re: CB750K4 New project
« Reply #39 on: January 08, 2018, 10:43:15 PM »
Stripped most of the bike down over the weekend, came apart quite well. Most of the stuff looks like it will be servicable. Carbs are in great nick, inlet rubbers have gone hard so will be replaced, exhausts ar inpretty good nick but will be replaced with a new 4 into 1. Engine needs removing for a check over and repaint.... overall no major concerns yet






Managed to get the master cylinder circlip out too

« Last Edit: May 01, 2018, 06:15:40 PM by Rob62 »

Offline Trigger

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Re: CB750K4 New project
« Reply #40 on: January 08, 2018, 10:47:52 PM »
Be careful with ordering a new master cylinder kit, a lot are listed but the wrong size. The two holes in the master cylinder need to be clear  ;)

Offline Rob62

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Re: CB750K4 New project
« Reply #41 on: January 08, 2018, 10:51:25 PM »
Tonight i had a look at the clocks, the lower chrome needs redoing and the upper could do with a repaint. So off with the crimp ring...

Cleaned the faces with a microfibre cloth and some vanish stain bar.... they are faded but cleaned up quite nicely, lenses cleaned up ok too, the difference is amazing. Will look great once back together.



« Last Edit: May 01, 2018, 06:16:49 PM by Rob62 »

Offline Rob62

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Re: CB750K4 New project
« Reply #42 on: January 08, 2018, 10:56:59 PM »
Be careful with ordering a new master cylinder kit, a lot are listed but the wrong size. The two holes in the master cylinder need to be clear  ;)
Cheers Trigger. Actually i already moticed that one of the two holes in the base of the reservoir looks to be blind drilled which seems a bit odd, the other goes straight through into the bore.... inside the cylinder is quite clean and rust free it was only the circlip groove that was rusted in. Ill get my magnifying glass out and have a closer look at those holes....
« Last Edit: January 08, 2018, 10:59:29 PM by Rob62 »

Offline Trigger

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Re: CB750K4 New project
« Reply #43 on: January 08, 2018, 10:58:46 PM »
Looks a lot better than the one I was working on yesterday. Very hard to get the chrome cups re chromed, as the metal is thin and the shape is hard to polish for prep.

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Offline Trigger

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Re: CB750K4 New project
« Reply #44 on: January 08, 2018, 11:02:20 PM »
Be careful with ordering a new master cylinder kit, a lot are listed but the wrong size. The two holes in the master cylinder need to be clear  ;)
Cheers Trigger. Actually i already moticed that one of the two holes in the base of the reservoir looks to be blind drilled which seems a bit odd, the other goes straight through into the bore.... inside the cylinder is quite clean and rust free it was only the circlip groove that was rusted in. Ill get my magnifying glass out and have a closer look at those holes....


You need a wire from a wire brush to poke in the hole that you think is blind, as it is not a blind hole  ;)