Topic: Bike Project - '75 CB750F

[DaveL]

I picked up this extremely ratty '75 CB750F for $400 (too much, I know). It came with a hardtail kit which I sold on eBay for $50 though. I brought this home and spent some time cleaning the carbs,  oiling the cylinders, and putting a new battery in it to see if the bike would even run. It ran, so I decided I'd fix it up. Then I found a much nicer F for a very good price and bought it (my avatar bike). Now I'm doing a build up on the first one.



and



It got uglier the more I disassembled it


 
At this point I have it fully torn down. I've cut the rear peg tubes, seat latch bracket, helmet hooks, center stand, and air box brackets, and ? from the frame and started sandblasting the frame. I ordered  a 3.5 x 18" rear and 2.5 x 18" front Excel rims and stainless spokes from Buchanans. I also just picked up an '04 CBR600RR front end from eBay (I wanted conventional looking forks).

[DaveL]

My plan is rather a lemming one, but I like the look! I'm going to make a cafe-ish bike with it. I want some newer bike benefits like better braking and handling, but I want the bike to still look 'period' to a degree. Right now I'm planning on retaining but modifying the stock F gas tank. I'm putting FZR rearsets on it and will fab up the seat and tail from aluminum. Right now I'm planning on welding up a stainless header, but haven't finalized the design yet. I'll post more when I've done more (I'm hoping to have it rideable by summer and would like to ride it to Carpy's summer thing if it happens)!

[Markcb750]

Welcome to my world...


http://forums.sohc4.net/index.php?topic=61929.msg672250#msg672250

[DaveL]

Looks like you have a ways to go too!

[Honda?]

Lol you can add me to the list of 750F restore junkies.

We should start a support group to see if we can swap parts or help each other with problems.  

http://www.wisconsinsportbikes.net/public_html/forums/showthread.php?t=10586

Btw how much did the rims and spokes cost you?

[DaveL]

Good idea.

I think the rims and spokes were around $550 or so?

[Honda?]

*shudder* 550 sounds about right.

I want to paint my rims black and polished spokes so non chrome rims should cut down on cost by a little bit.

[Staggerlee]

Hey, it's Dave!

Git on that thing man, fairer weather approaches!

[DaveL]

Damn skippy! It's quite nice today - a real teaser. I may have to take the blue bike out for a spin on break!

[Staggerlee]

Yeah, that bright orb is in the sky down here as well.

[DaveL]

Progress is slow. When you work all day in your shop for a living it's tough to go back in the evening to work on your own stuff! I have some '04 CBR600RR forks, brakes, and clip ons to mount now. The steer tube on the 600 forks is a little too short for the 750 frame though. I've pressed the tube out and will counterbore the lower triple so the steer tube fits 'deeper' in to it - effectively lengthening the tube. I'll find out tonight if that works well. After that I'll mill the 750 front hub down and build some bearing housing/adapters similar to FunJ's to adapt the 600 rotors to the 750 hub using sealed bearings from All Balls.

Pictures at 11 (my kid used up the camera batteries over the weekend)!
Centering



boring



Problem with All Balls bearings now. The top one sticks up way over the top of the head, and there's no way the top  seal will cover it. And the bottom seal is so tight that when the bearing is pressed down over it the seal keeps the bearing from spinning.

[Staggerlee]

c'mon, c'mon, c'mon; lessee the pictures!

[DaveL]

Well, All Balls said they're aware of the overly tight lower seal and were "working to address it". They said to use it anyway and that it was a 'feature'.
Here is the first test fit of the forks:



And here is what may be a spoke clearance problem:



Now I've got to find the "official" rotor spacing so I can make the hub adapter/bearing housings so I can build the wheel so I can see if the spokes will clear 

[Staggerlee]

Looks great Dave!

[Doctor_D]

Same bike, same general region, same time-frame, same concept even...

http://forums.sohc4.net/index.php?topic=66026.0

Good luck.

[DaveL]

Same bike, same general region, same time-frame, same concept even...

http://forums.sohc4.net/index.php?topic=66026.0

Good luck.

You might actually be a little ahead of me 

[DaveL]

Looks great Dave!

Thanks! but I have a very long ways to go, and you're already riding your badass mo-chine!

[traveler]

Looks good so far.....make sure you read the tips/tricks, and take care of engine problematic areas when rebuilding.

~Joe

[Staggerlee]

Thanks! but I have a very long ways to go, and you're already riding your badass mo-chine!

True, but I've got a feeling that you'll be catching up in no time.  It's not like this is your first rodeo or anything.

[DaveL]

Here's a crappy cell phone pick of the front hub with rotor adapters. I also turned the 'middle' of the hub down to smooth it and remove the ribs. Maybe I'll put a leather strap around it like on  my bicycle when I was a kid?

I'll turn up some new spacers today and maybe get to start lacing my wheel up (if I can decide what to do about finish coatings for the hub anyway).


I've also drawn up the parts for a custom aluminum swingarm I'm building, and once I get new belts on my CNC plasma table I'll cut those out and start welding it up. Pics to follow...

[traveler]

outstanding!  Thanks for the update!

~Joe