Topic: seanbarney41's 1975 CB750F!

[seanbarney41]

Always meant to do a project thread on this but never got started.  But hey, I took lots of pics.  It was finished about July '17?  I have since already put 3000 miles on it and couldn't be happier.

Here it is when I bought it...
DSCN1033 by Sean Barney, on Flickr
DSCN1034 by Sean Barney, on Flickr
DSCN1035 by Sean Barney, on Flickr
DSCN1036 by Sean Barney, on Flickr
DSCN1037 by Sean Barney, on Flickr
DSCN1043 by Sean Barney, on Flickr
I paid $1100 to a good acquaintance.  He lives about an hour away, so we don't hang out regularly.  He had bought it from the original owner about 4 or 5 years before and rode it regularly until he got a Duc Monster.  He started out trying to get $2300 for it, and no one was interested.  He backed it down to $1800, so I told him I would have a look.

[seanbarney41]

I really wanted the original paint but the wiring was wasted and it started very reluctantly and rode basically like #$%*.  I knew it would need everything but engine rebuild and paint.  I offered him a grand.  He refused.  I said ok then, and said goodbye.  I was climbing in the van to leave when he ran up and blurted $1100!  Sold.

[seanbarney41]

So back at the shop...where to start?  I think I got this thing fall of 2015, never got started on a project thread, had a computer crash, then just replaced with a notebook that was incompatible with my camera so it's kinda hard figuring out what all I did when.  I will do my best here and I hope someone learns something or at least enjoys some bad writing and pics.

Brakes were hanging up so let's say that was first.  Did a quick clean and polish on the front.
DSCN1042 by Sean Barney, on Flickr
DSCN1045 by Sean Barney, on Flickr
I used a spare master cylinder to push the piston out
DSCN1046 by Sean Barney, on Flickr
DSCN1047 by Sean Barney, on Flickr
front brake was now functional and the bike was ready for more test rides.

[seanbarney41]

The bike was still a hard starter and so I r&red the ignition first.  Surprisingly, this was one area where the PO had done good as I found good testing coils, only one bad plug cap that was immediately replaced with a used spare and nice oem points and condensors that were already set spot on.  So I pulled some plugs.
DSCN1041 by Sean Barney, on Flickr
fouled..checked the air filter and it very well may have been original.  So I chucked it.  For plugs?  Had to resort to the secret weapon ha ha
DSCN1039 by Sean Barney, on Flickr
No seriously, pulled those out of a parts bike years ago and ever since they have not failed to start anything they screw into.  I did put the proper NGK's in at the earliest opportunity.  So another test ride had the Fer running on all four with a big lean out at about 6500 rpm.  Plugs now looked like this
DSCN1040 by Sean Barney, on Flickr
I checked the main jet...105's and no filter in the airbox.  Sounds about right.
     So somewhere around here, it became winter.  Which, in Kalamazoo, Michigan, includes lots of nasty rain, cold, and snow, so the testing and tuneing got set aside until improvements in the weather.

[seanbarney41]

Oops, see?  I should have probably thrown this post in with the front brake.  Just wanted to let y'alls know, you don't have to always bin those damaged old Honda parts.  This brake lever is certainly not useable if you have normal human hands.
DSCN1049 by Sean Barney, on Flickr
but it was easily repaired, no special oxyacetylene torches or hydraulic presses required...
DSCN1050 by Sean Barney, on Flickr
DSCN1051 by Sean Barney, on Flickr
DSCN1052 by Sean Barney, on Flickr
I compared it to a spare I had.  Good enough for who it's for.
DSCN1054 by Sean Barney, on Flickr

[chiefum]

Looks nice, I  like the color.

[seanbarney41]

I spent pretty much the whole winter of 2015/16 working on the wiring.  Why so long?  It was really bad.  I repaired most things and replaced very little.  Electrical repairs are very time consuming and I am electrically "slow".  The wiring diagram for this particular year and model has got to be the most complex and confusing of all the sohc4 bikes.  The few parts I did replace, proved to be hard to find.  I did not restore it to stock.  And I was working on at least 2 other projects at the same time.
     The bike's original key switch had disintegrated before I bought it on an out of state ride and the PO ended up having some independant bike shop rig something up to get him home and that was how he left it.  He actually purchased a nos Honda switch and key set but never installed it and it was for a K1-K6.  He had included it when I bought the bike.  I used it.  I ditched the between the gauges indicator dash and used the handlebar clamp one from the earlier K's. 
I don't think I ever really figured out what did what with these switches
DSCN1185 by Sean Barney, on Flickr
Pretty sure most here are familiar with this pic.
DSCN1187 by Sean Barney, on Flickr
some kinda success going on here?
DSCN1188 by Sean Barney, on Flickr
I used this nifty Triple A relocation bracket that I found at a swap meet to mount the nos early K key switch
DSCN1191 by Sean Barney, on Flickr
DSCN1192 by Sean Barney, on Flickr

[seanbarney41]

Looks nice, I  like the color.

thanks, I like it too.  Let's thank Honda for doing such a good job painting these back then.

[seanbarney41]

Anyway, I think I managed to save the handlebar switches.
  KIMG0016 by Sean Barney, on Flickr
Big thanks to M.Rieck for coming up with a NOS F/F1 only wiring pouch thingy that hangs on the frame.  So I found some difference between the original and the NOS replacement...really weird on a one and half year only part.  Oh wait!  550f's have these too?
KIMG0014 by Sean Barney, on Flickr
I whipped up a little aluminum bracket to adapt earlier K gauge mounts to the F top triple and retain the very unique headlight mount bracket.
KIMG0021 by Sean Barney, on Flickr
KIMG0022 by Sean Barney, on Flickr
This later got painted black to blend in and better fitting hardware.

[seanbarney41]

PO's clubmans got ditched here too...used some cb400f repro's bought from a member here.

[jamesw]

Love that colour! Nice pick up.

[seanbarney41]

At this point I am gonna go ahead and create a new word ..."gefwif"  It's gonna get used a lot in this thread, I think?  It means...good enough for who it's for. lol

[seanbarney41]

Love that colour! Nice pick up.

Hi James

[seanbarney41]

Somewhere during this stage, I decided I was very fond of the generally good condition chrome cover kit that had been installed on the engine.  Only problem was the stator cover was MIA, probably ruined in a get off at some point, and had been replaced with an also rashed standard aluminum one.  Big thanks here to Mr. B. Benton for having an awesome horde containing a beautiful spare.
KIMG0048 by Sean Barney, on Flickr
I opted not to re-use the studs with chrome acorn nuts here as you could not even get a proper socket or wrench on 'em due to the recesses in the covers.  I grabbed the Alloy Bolts polished kit off ebay and slapped in new gaskets as well.
KIMG0049 by Sean Barney, on Flickr

[seanbarney41]

Then, at this stage, I realised, that shiny engine was gonna cause big trouble...all the aluminum would have to get polished to match.  This is gonna mean a lot of gefwif...cause my polish patience is just gone.

Here is the rear brake overhaul and polish...

Pistons came out easy, I used compressed air this time.
KIMG0043 by Sean Barney, on Flickr
KIMG0044 by Sean Barney, on Flickr
pretty good stuff...anything that can get at this tough Honda paint can't be too bad
KIMG0045 by Sean Barney, on Flickr
you will notice I am doing an early K front caliper here too...more on this later
KIMG0046 by Sean Barney, on Flickr
KIMG0047 by Sean Barney, on Flickr
KIMG0051 by Sean Barney, on Flickr
I used this die grinder to get the big hammer dents out.  DON'T try and use one of these to save time polishing.  It will dig big holes FAST, even with just a scotchbrite pad, and you will have to spend even more time trying to smooth things out by hand.
KIMG0052 by Sean Barney, on Flickr
KIMG0053 by Sean Barney, on Flickr
KIMG0054 by Sean Barney, on Flickr
A quick note on my technique...I start rough with 80 or 100 grit to get the big pits, flash, dents out fast.  Then quick wheel buff.  Then 120 grit.  Then wheel buff.  Then red scotchbrite.  Then final with the wheel.  This is not good, its gefwif!  If you want quality polishing you have to go much higher grit.  I am too lazy and my technique gets stuff gefwif reasonably fast.

[Stev-o]

Better late than never.   I like the lever straightening method shown, I may try that one day, rather than just trashing it. 

[seanbarney41]

Better late than never.   I like the lever straightening method shown, I may try that one day, rather than just trashing it. 

It's super easy Steve-O...they will break sometimes though.

[seanbarney41]

More oops...found more with the nos wiring pouch thingy...
KIMG0023 by Sean Barney, on Flickr
that has all got to fit in
KIMG0024 by Sean Barney, on Flickr
here.  And y'all thought your K1's headlight bucket was bad!

Speaking of which?...more gefwif.  Really should have re-painted.  Before
KIMG0026 by Sean Barney, on Flickr
After a little polishing compound.
KIMG0028 by Sean Barney, on Flickr
I'm obviously not totally opposed to letting these old bikes look old.

[seanbarney41]

One thing I have never liked about cb750's is the basic ergo's.  They are a big guys bike and I am not so big, err tall anyway.  Stock riding position leaves my short little arms and legs feel all stretched out and out of control.  So I got the low bars but what to do about the foot controls?  No bolt on Tarrozi's rearsets for the F, which would be my first choice.  I got to digging in my stash and found a totally haggard set of cb400f pegs and controls I had bought for a cb550.  I no longer own a cb550.  I started eyeing things up and lo and behold the pegs bolt straight on!  And move your feet back and up about 2 inches each!  That will be perfectly comfy and performance improvement to boot and look stock!  #$%* hot!  The bad is the shift pedal and linkage will never work.  So I mocked up a shorty shifter made from some other shift linkage, a bolt, some nuts, and a piece of rubber hose.
KIMG0104 by Sean Barney, on Flickr
This put the toe piece in the perfect spot but it was too short for good leverage.  No pic unfortunately, but I ended up sectioning a stocker lever so it is a little longer than what is pictured.  I have to move my foot to shift now and it is still too short for good leverage.  Not the hot drag race set up, but it works.  I have a vague plans and raw materials to improve this asap.

For the brake side, I just dug up a semi random brake pedal and shortened it.  Just cut the welds pulled the tubeing off the slug, cut the tubeing shorter, stuck it back on the slug, and had my buddy zap it back together.
KIMG0103 by Sean Barney, on Flickr

[seanbarney41]

Forks got overhauled, new seals, fresh oil and some badly needed tapered steering bearings...
Polished lowers too
KIMG0106 by Sean Barney, on Flickr
A local bikey machinist builds these trick tools for working on your forks...
KIMG0110 by Sean Barney, on Flickr
KIMG0113 by Sean Barney, on Flickr

[Terry in Australia]

Looks good Sean, you were lucky to get a nice sound bike to start with, and I love your Rednecking attitude, like me you know that beauty is way more than just skin deep, and a bit of patina is something that should be admired, not covered up with a can of VHT. They're only original once. Good job.

[seanbarney41]

I decided it was about time to do the good old dual disc swap using the stock fork legs and an extra caliper and disc and this was the bike to do it on.  I had all the parts, or so I thought.  I sent three rotors, two fronts and one rear,  out to Goddfrey for drilling and thinning...not required but man does he do beautiful work.  Here is the rear.
KIMG0098 by Sean Barney, on Flickr
He also sells a trick little inexpensive kit to get your speedo drive to work with the extra front disc.  Highly recommended and Goddfrey is truly a pleasure to deal with.
I had decided to use k2-k6 calipers as I have plenty of extra's and one was all rebuilt ready to go.  I only had the one F caliper.  Unfortunately, after the k calipers were all rebuilt and polished, I discovered that a K caliper will not work on the right fork leg.  They work fine on the right.  It is because the pivot arm has a different bend to it and you cannot interchange the k and f pivot arms either.  I also discovered that, even though cb550 calipers look the same, they are much smaller in several dimensions.  Luckily, Ekpent saved the day with a spare F caliper just a couple miles away.
    The caliper on the right leg is not a bolt on and I spent a few weeks fiddling around getting everything to work.  I really don't even remember exactly what had to be done to get it right.  I had to shim my caliper towards the wheel to get it aligned.  Here are pics.  Wish I had better ideas about what the hell was really going on.
mmm them Goddfrey discs
KIMG0118 by Sean Barney, on Flickr

Here you can see the difference between the caliper arms of a k2-k6 versus the f.  Whats wacky is either will work on the f's left leg, but  the k won't work on the right.
KIMG0124 by Sean Barney, on Flickr
oh yeah...you can see here that the k caliper must be shimmed out so much that it hits the spokes
KIMG0121 by Sean Barney, on Flickr
I used stainless washers which, here, are electrical taped into a single stack for installation ease.  I think this pic is with the k2-6 caliper arm, so I ended up with less shim for the f arm. 
KIMG0122 by Sean Barney, on Flickr
 
It was totally worth it in the end.  I finished up with braided stainless lines from Earl's and a used ebay 16mm Suzuki Bandit master.  I initially tried a 14mm and couldn't get a firm lever.  This bike stops better than my cb750 with gl1000 front end and a 16mm cb750f2 master.

[seanbarney41]

Looks good Sean, you were lucky to get a nice sound bike to start with, and I love your Rednecking attitude, like me you know that beauty is way more than just skin deep, and a bit of patina is something that should be admired, not covered up with a can of VHT. They're only original once. Good job.

Dang!  This bike must be good to get Terry to compliment an F!

[seanbarney41]

Wow!  Just looked at the clock...it's 8:36pm!

[seanbarney41]

So, many seasons had come and gone since I bought this bike.  But now it was late spring and the time was right for riding.  Fortunately, I had at least a couple other bikes to ride, but dangitall, I wanted to ride this one.  Time to get some exhaust on her and get the thing tuned up.  The bike came with a stock header with a cheap, crap sounding MAC slip on.  The stock header ended up interfering with my brake pedal mod, so that was out whether I could find a decent muffler or not.  I had acquired a Carpy Yosh rep for silly cheap but I really didn't want the noise.
KIMG0057 by Sean Barney, on Flickr
Point was moot anyway because I couldn't strong arm the pos enough to make it fit.  Ended up selling it to Slikwilli420 who apparently has stronger arms than me 'cause he wrangled that #$%* on to his race bike.  So then I tried this old 4 into 1 but the can went bang on something too, can't remember what.
KIMG0158 by Sean Barney, on Flickr
Anyway, I realized, whatever pipe, It had to be chrome...Enter a hacked up old Kerker, that I had to have welded to use, and I had to beat the #$%* out of a Kerker can to get the cut off stub of another header out of the inlet.  The baffle did not survive the carnage.  And I still can't get the end cone off to install a new baffle.  So it's louder than I wanted, but with just the end cap, it is tolerable, only because it sounds like nothing else.  You can seriously play the thing like a trombone with just a twist of the throttle.
Here is the bloody aftermath of the Kerker hackfest...that is my buddy, Fred, doing what all my shopmates do while I sweat and toil and bloody hack away at things until a functioning vehicle rises from the rubble...
KIMG0163 by Sean Barney, on Flickr