Author Topic: 1975 750f (Read 24598 times)

sixthwisconsin · « **on:** January 20, 2012, 06:21:59 pm »

So I bought this buggered up 1975 cb750f. The motor falls into the 1975 range (250XXXX) and the frame falls into the 1976 range (200XXXX). Comstar rear wheel and a spoked front. (going spokes all the way).

The California title, which has both the frame and engine number on it calls it a 1975.

You are getting a glimpse of where i am right now.
Wiseco 836 kit and jugs bored.
Cam, studs, valves, porting, springs, guides, chains. need alotta stuff...

Bought the 1976 gl1000 front end from milwaukee cycle salvage. Got the triple, forks, disks, calipers, fender, rim, hub and hardware.

Here is my work bench tonight.
I apologize upfront for the disjointed timeline.

And as I bought it

Tews19 · « **Reply #1 on:** January 20, 2012, 08:06:36 pm »

Sweet, you posted your build!!!! This shall be very interesting.... Will you be keeping the 550? Also, what are the plans about the seat?

SUBSCRIBED

madmtnmotors · « **Reply #2 on:** January 21, 2012, 07:06:01 am »

Looks solid. Love the color-coordinated duct tape on the seat!

sixthwisconsin · « **Reply #3 on:** January 21, 2012, 09:54:16 am »

Quote from: Tews19 on January 20, 2012, 08:06:36 pm

Sweet, you posted your build!!!! This shall be very interesting.... Will you be keeping the 550? Also, what are the plans about the seat?

Oh yeah, I'm keeping the 550...
The seat fairing was made from a tank (gas tank that is).

Quote from: madmtnmotors on January 21, 2012, 07:06:01 am

Looks solid. Love the color-coordinated duct tape on the seat!

The whole bike is kind of like that! Held together with duct tape and rigging wire...

sixthwisconsin · « **Reply #4 on:** January 21, 2012, 10:07:33 am »

A couple more shots of it coming apart:

Some bad looking stuff up top. Now you know why I'm replacing everything!

carbs rebuilt and going back together

A little help from the grand kids...

brandEn · « **Reply #5 on:** January 21, 2012, 10:28:27 am »

Wow that cam is TOAST!

lucky · « **Reply #6 on:** January 21, 2012, 01:32:28 pm »

In all of my years working on bikes I have never seen that much damage on a cam.
Something caused that, that was not the normal treatment.

Tews19 · « **Reply #7 on:** January 21, 2012, 01:38:07 pm »

What is a good phrase that could be used for that cam abuse? Im thinking something clever like when someone spills an adult beverage and screams alcohol abuse.

In regard to the engine coming out, is it pretty easy to take out with the front and rear end on still? I want to put my bike together and have the engine be the last thing I put in.. Advice?

sixthwisconsin · « **Reply #8 on:** January 21, 2012, 06:14:42 pm »

Quote from: brandEn on January 21, 2012, 10:28:27 am

Wow that cam is TOAST!

Quote from: lucky on January 21, 2012, 01:32:28 pm

In all of my years working on bikes I have never seen that much damage on a cam.
Something caused that, that was not the normal treatment.

Yes, I was really supprised to see this. The oil port to the right side of the top end was plugged and the bike was run hard like that. The damage is severe but believe it or not, it was running when purchased.

Quote from: Tews19 on January 21, 2012, 01:38:07 pm

In regard to the engine coming out, is it pretty easy to take out with the front and rear end on still? I want to put my bike together and have the engine be the last thing I put in.. Advice?

Not an issue removing or installing the engine with the front or rear wheels installed on the 550 or 750. Just follow the downloadable service manuals. I think they both are removed and installed fron the right side.

sixthwisconsin · « **Reply #9 on:** January 22, 2012, 05:03:10 pm »

todays work...

tore the gl1000 triple apart and started stripping aluminum bits for polishing later. Got the rear hub, lower fork cases and valve cover stripped and ready for the polishing wheel.

Need to get a list of engine bits together before I call cycleX. Going to have them do the porting & crank work. I figure a road trip is in order to pick up parts and drop off head, crank and rods. I think they are about 3 1/2 hrs north of me.

sixthwisconsin · « **Reply #10 on:** January 29, 2012, 06:44:00 pm »

Finished the polishing of parts.

WHAT A PITA!!
This is absolutely my least favorite part of the job...

Spent the day cutting out spokes and polishing up al-u-minium parts.

Got my list together for cycleX...
Oh boy, I might not be posting for awhile until I can afford their stuff!
(Plans are to go up on 2/11, gotta call them this week)

lucky · « **Reply #11 on:** January 29, 2012, 08:10:51 pm »

Quote from: Tews19 on January 21, 2012, 01:38:07 pm

What is a good phrase that could be used for that cam abuse? Im thinking something clever like when someone spills an adult beverage and screams alcohol abuse.

In regard to the engine coming out, is it pretty easy to take out with the front and rear end on still? I want to put my bike together and have the engine be the last thing I put in.. Advice?

Lift the bare frame off of the engine.
Lower the bare frame over the rebuilt engine.

madmtnmotors · « **Reply #12 on:** January 30, 2012, 04:42:10 am »

Quote from: Tews19 on January 21, 2012, 01:38:07 pm

What is a good phrase that could be used for that cam abuse?

What kind of cam "grind" is that?

bjbuchanan · « **Reply #13 on:** January 30, 2012, 10:00:15 am »

Go in to the FAQ section there and check out the engine section. They have a removal/install thread that i used and it worked great.

Support the engine with straps (or in my case monster zip ties) on the alternator and points humps and let it hang from two lifted jack stands. Move the frame to the engine and it goes real nice. Super easy with 2 people and not bad at all going it alone

Heres the link for some pics:

http://forums.sohc4.net/index.php?topic=71240.0

sixthwisconsin · « **Reply #14 on:** January 27, 2013, 08:16:11 am »

So in my last post I said I would not be posting for awhile. I didn't really think it would be A YEAR! I kind of took some time off I guess. I bought a nice sport touring bike in late March last year and rode the hell out of it all summer. I put about 7000 miles on it and had a blast. Here is a shot the day my buddy and I left for a 10 day ride out east and through the Shenandoah mountains. Mine is the Kawasaki.

Back to the 750...
Bought the following engine parts:

Cycle X lightened & balanced crank
Cycle X super connecting rods
Wiseco 836cc piston kit
MLS steel head gasket
Ape super studs
Cycle X lightened alternator
Cycle X race transmission
Cycle X super clutch with coated steels
Full gasket kit and seal kit
New oem Primary chains
New oem Primary chain tensioner
Heavy duty cam chain
CX-3 Cam
28.5mm Oversized Super flow Exhaust Valves
33.5 Oversized Super flow Intake Valves
Kibblewhite Bee-Hive valve springs
Cycle X ported the head and assembled
Cycle X ignition kit
hondaman fuse holder

I've got the engine mostly done and will be turning my attention to the frame next.

hoodellyhoo · « **Reply #15 on:** January 28, 2013, 07:02:05 am »

Nice project you have going here. I wonder what the engine sounded like with that cam damage

I don't know what your plans are for that muffler but if you aren't using it there is a member looking for that black end cap (in the parts wanted section)

Bankerdanny · « **Reply #16 on:** January 28, 2013, 07:31:22 am »

I think using the back of a tank as a cafe seat rear is actually pretty inventive. I'm really surprised that I haven't seen it before.

Too bad you have your GL front end already. I could have pointed you to a salvage yard here in IL that has two '78 F bikes that could have donated front clips with the matching twin disk Comstar front wheel. Although I may grab one of them for the 550 I am starting on.

sixthwisconsin · « **Reply #17 on:** January 28, 2013, 03:42:28 pm »

Quote from: Bankerdanny on January 28, 2013, 07:31:22 am

I think using the back of a tank as a cafe seat rear is actually pretty inventive. I'm really surprised that I haven't seen it before.

I saw one at a show once that I thought was really nice. This one seems a bit big to me. Maybe I'll offer it up for sale here one of these days.

sixthwisconsin · « **Reply #18 on:** February 07, 2013, 05:14:10 pm »

So I looked back at some disassembly photos and ran across these. The nut on the right end bearing cap worked its way off and is down sitting next to the head nut. Don't know if I stated this before but one of the top end rubber pucks was a washer covered with sealant!

Work continues VERY slowly on this build, but it continues. buttoning up the top end soon and working on the frame mods. Will be installing the slotted cam sprocket, coated rockers and shafts, and the cam tower stabilizer rocker cover soon.

sixthwisconsin · « **Reply #19 on:** March 12, 2013, 05:37:03 pm »

A bit of progress...
Motor pretty much done. Rocker cover off for polishing and cam degreed. Currently working on the frame. Thinking of having the cb550f header as well as the cb750f header black ceramic coated at the same time.

sixthwisconsin · « **Reply #20 on:** September 07, 2013, 07:08:04 am »

This build is moving slowly but it is moving. Here is where I sit today.
I should have a roller very soon as I have most of the new parts needed and the wheels are off for lacing and new rubber.

Lowered the frame over the engine

The color doesn't reproduce well. It is very close to Corvette Magnetic Red.

sixthwisconsin · « **Reply #21 on:** September 08, 2013, 07:27:39 am »

A little more progress yesterday.

Fitted the All balls tapered bearings and installed the gl1000 tree.

Installed the Hondaman rebuilt swing arm and the Hagons.

Tews19 · « **Reply #22 on:** September 08, 2013, 09:32:27 am »

The frame paint really makes the black pop... What's the plan for tin color?

sixthwisconsin · « **Reply #23 on:** September 08, 2013, 01:28:48 pm »

Tank and seat pan will be black.
Need to stretch the width on the seat pan first because I want it to fit right down on the frame. I think I have the same as your build from Rock City.
I need to split it down the middle in the seat area, stretch the width and reglass to fit the front of the frame.

Now that I am actively working on the bike I should be getting to this soon.

sixthwisconsin · « **Reply #24 on:** September 14, 2013, 06:47:30 pm »

A bit of progress today.
Visited Jeff, aka Godffrey today and picked up these...
Didn't expect he would have all 6 disks (for me and my buddy who is doing a similar build) in stock! After a trip to the local ATM, I was on my way home.
He dose great work!

fork tube bolts for the gl1000. That is Manx 10 pence that I will embed on the top of the bolt. Still looking for one bolt if anybody has one!

Got the Tarozzi rear sets yesterday. Perfect fit. The rear brake will have to wait until I get the rear master cylinder rebuilt and some powder coating done.

Front forks rebuilt. Thinking of adding Racetech emulators before installation.

News:

Author Topic: 1975 750f (Read 24598 times)