Topic: CB750A Barn Find - Slow Build / Cheap-A$$ Driver

[raymond10078]

Finally getting around to posting about my bike.

I bought it as a true "barn find".  Hadn't run in 14 years, and had 14,000 miles.  Paid $300, and my wife thought I was crazy (probably right).



Oh - the short in the taillight was actually a shorted/melted ground wire - had to replace the harness.

Rebuilt the carbs, new tires, new (and cheap) mufflers on stock down pipes, new brakes shoe/pads, rebuilt the master cylinder and calipers, halogen headlight, lower handlebars, and then just rode it for a while.  Ugly warts and all.

While riding it, I slowly made upgrades:

• Ran into a charging system problem - and installed a solid state voltage regulator
• Put on some cyclexchange rear shocks
• Installed a Pamco ignition

THEN, bought a new(er) home in a neighboring city (a repo), and that has been consuming most of my time ever since.  So, it's been (mostly) sitting for over a year - waiting on me and my time - but I've been collecting parts in the interim.

My goal is to make this bike look like it may have if Honda kept making them into the early 80's.  This is a low buck build.  I figure that I'll own this bike for the rest of my life, and I'll keep upgrading it as I go along.

Anyway, tonight I finally put on the rear reverse comstar (from a 79 CB650 with new wheel bearings), and a NOS RK 630 gold chain (new front sprocket, too).





Parts I have waiting:

• Yamaha Seca CV carbs
• Bar end mirrors
• 750K cam
• CB750F front wheel with dual discs and new wheel bearings
• CB750F front forks (fresh black paint)
• Progressive suspension springs
• Yamaha low "stiction" fork seals
• Air caps/guage for forks
• CB900F calipers (painted gold)
• Tapered steering bearings
• Different tail light
• 80's style turn signals (black stems)
• CM450A style parking lock (looks like a clutch lever - mounted on the left handlebar).  I want to have lever on both sides - just like the later/smaller Hondamatics
• 76/earlier carb boots
• 72/earlier rocker arm set (not bolted so they will rotate - Hondaman tip)

 



Additional plans:

• 750F speedo and tach, either from a 75 to 78, or up into the early 80's
• custom made luggage rack - width will be about the same as the seat, and taper/narrow towards the rear
• may do a chopped rear fender - that carpy has for sale
• oil cooler
• new coils
• paint job - never done one - not sure if I want to tackle that or not - but I do like the two-tone paint jobs that Honda had from 79 on.  If you look at an 82 CM450A in blue - that's my first choice of colors.
• paint the engine black

[raymond10078]

I did just recently (last two weeks) replace the JIS head screws with later hex head screws (used on later Hondas).

[raymond10078]

No pics for today.

Stripped off the front end yesterday.  Just the triple trees remain.

Was surprised to find how much tight the triple trees are (hard to turn) and that they have a "detent" when centered.  I know this isn't right - but was surprised at it none-the-less.  Didn't feel it riding down the road.  I posted a vid of the detect here:

http://forums.sohc4.net/index.php?topic=135110.0

Also - bought a 78 speedo/tach this morning from fleebay.  Hope it works out.  I'll lose the parking light - but that doesn't worry me at all.  It will be interesting to have a tach.   

Now, just have to deal with the wiring in the headlight shell.  That is one my least fun things to do.   

[raymond10078]

Received my oil cooler adapter this week.



Bought it from TDR400 - from South Africa!  Nice unit.  Best design (IMO) that I've seen in a while.

Now, need to find/select an oil cooler . . . .

[raymond10078]

Also swapped the tire over from the old rim to the new(er) rim.  Mounted up the discs, greased the speedo drive, and installed the axle.  Waiting for the steering head/forks to be mounted up!

[raymond10078]

Busy day!  Also received my new(er) tach - swapped over my "A" speedo, and now its almost ready to bolt on.  I plan on  fabbing up stock "A" connectors so I can just "plug and play" the new speedo/tach unit.

[raymond10078]

Triple trees off, new bearing cups installed.





When putting in the All Balls bearings, other posts refer to grinding down the "lip" inside the retaining nut.  Looking for an alternative - thinking about a shim.  I'll post about his later, when I get it solved.

[raymond10078]

Calipers assembled - back on the shelf waiting on the forks.

[raymond10078]

Forks on!



I chose to buy a shim (Honda part number 90487-700-000), and then grind down the steering nut "lip" so it is slightly lower as compared to the shim.  As is documented in other threads, the upper bearing top side doesn't fit into the steering nut "lip", so something had to be done.



The red circled area was my first attempt to grind down the "lip", was trying to go nice and flat.  Then found the Honda part, and came up with Plan B - to only grind down the "lip".



Comparison of shim and bearing.



Shim and bearing stacked.



Shim laying in steering nut.