Topic: CB750 K6 - Step Step 12 - Now into some tweaking to get it right

[oldhatt45]

Hey Guys,
I'm pretty new to the forum but not new to the CB750 K6 (1976).
Have read many of the threads on the forum about rebuilds, restores, etc.
I own a CB750 K6 and have owned it since it came out of the box.
Unfortunately, it's been sitting in my various garages for the last 26 years.  The first 3 of which it was originally covered and waxed for the winter (of 1985-86).  During that first 3 years it got uncovered and looked like my ex had hit it with a garden hose.  So anyhow, that is the sad part of the story.

I have now started to bring the old 750 back to life and get her looking the way she should be and hopefully go riding again.

Here is a picture just after I pulled the front forks:


I'm working on cleaning the fork legs as step 1.
I have used a paint stripper to get the old beat up clear coat off and have the right leg pretty much sanded out to 1200 grit.
It's looking pretty good.  I was able to sand out the very tiny pit marks with 220 grit wet/dry paper and then work my way up to 1200 grit.
Then I started on the Left fork leg.  That leg is proving to be a bear in trying to get the tiny pit marks out.  I don't know if they will show up in the pictures, but I've been working on it for about 4 days now.  When you look at the leg under the lights, you can see the marks but you can't feel them with a finger nail.  Outdoors, you really can't see the pit marks unless you get pretty close.


So, my question is this.  Do I consider the left leg done or keep sanding to try and get the pit marks out?  Will buffing with a wheel help at the end or even now? 

I would appreciate any and all help and opinions.
Thanks,
Charlie

[SOHC4 Cafe Racer Fan]

I think a Harbor Freight buffing wheel will help get polish out the superficial marks -- if you have removed the pitting and wet sanded.  Use the different grades of rouge polish.

That is some handlebar riser set up you have going on.

Bummer about the ex hosing your bike, and causing more oxidation.  It still looks fairly clean, especially the paint.  How does the gas tank look inside?

[oldhatt45]

CB750 Café Racer Fan,
I am going down to Harbor Freight today anyway for something else, so will pick up a buffing wheel and rouge.

The handlebar setup is something I bought to make life more comfortable back in 1976.  LOL  What is not in the picture is a Vetter Windjammer SS, so the setbacks may look a little drastic but it does put the bars back where i'm comfortable and actually does not raise the handlebars.  LOL

The inside of the tank is very good.  Tank is still full of 26 year old gas right to the brim.  So, I expect a lot of varnish and will have to deal with that and am planning on a complete carb rebuild in any case.

Thanks,
Charlie

[oldhatt45]

I picked up the buffing wheel from Harbor Freight and a few other things I could not do without.  LOL
One of the things I picked up was a buffing kit for attaching to a drill.
In the kit is 3 different grits of buffing compound.
Given that I have sanded the forks out to 1200 grit and they are pretty nice now, what grit buffing compound should I be starting with?  Course (Black), Medium (Red) or Fine (white) are my choices.
Also, which buffing wheel should I be using? 
Thanks

[kammery]

 I had the same thing on my CB550 and CB750 .  I used a fine tooth file and went over the scratches .  Slowly I went over a large area where the scratches were at the went over the area with 220 wet paper . took some time turned out as good as new .

[WhyNot2]

Use different wheels for different color buffing compound.

[oldhatt45]

I'm almost done with the sanding on the left fork leg.
I've updated this thread where I posted more detail
http://forums.sohc4.net/index.php?topic=138689.0

But, the sanding is almost done.
Here is a picture showing the left leg.
To the left of the sandpaper is the 1200 grit to the immediate right of the sandpaper is 800 grit (but where the old inspection sticker was and farther to the right is the real 800 grit.

It was mentioned that 220 grit seemed too aggressive, but considering that it took me about 20 hours worth of sanding with the 220 grit over 5 calendar days, I can't imagine what starting with 400 grit would have taken.

I ordered some green/stainless compound and some jewelers rouge so that once I'm done sanding I can start the polishing and buffing. 

I appreciate the help that several of you guys gave me in figuring out the steps.

[oldhatt45]

While I have been working on the fork leg cleanup, I have been accumulating some parts I know I am going to need.
would like opinions, suggestions or advice on what I've got so far and even if I forgot something.

The parts I've gotten so far are:
1.  New Brake lines - Line A, Line B and the hard pipe.
2.  Master Cylinder rebuild kit
3.  Caliper rebuild parts - Piston, seals, etc
4.  Caliper adjustment bolt, spring, nut and washer
5.  New Front Brake Pads
6.  New Rotor - mine is/was pretty rusted up.
7.  Have my fender, stays, case guards, headlamp ears, Tach and Speedo cases out for rechroming  (Should have  them back on Thursday)
8.  Have contacted Powderman about redoing the switches and Master Cylinder.  (I think I owe him some pictures)
9.  NOS DID Rims, rim bands, spokes and tubes.
10. Conti Go tires 3.25 X 19 Front and 130/80 X 18 rear
11. Fork Seals and dust covers
12. Elans oil stopper kit and pan gasket
13. Throttle Cables
14. Front wheel bearings and seals

Plan to order very shortly
1.  Progressive Suspension - progressive rate fork springs (I have old S&W progressive rate springs in the forks now. they are 28/48)  The only fork springs I see from Progressive have spring rates listed as 30/50 and wonder if there will be much difference from the old ones.)  Also, I have/had 30 weight BelRay oil in the forks and have read a number of threads that all seem to use lighter weight oil. 
2.  Swing Arm Bushings
3.  New Shocks or Rebuild (more likely have someone rebuild) my existing Koni Shocks. 
Both the S&W fork Springs and the Koni Shocks were put on before the 750 rolled out the door on day 1 in February of 1976.
4.  Rear Wheel Bearings
5.  Rear brake shoes
6.  New Chain (Don't know whether to get one of the O-RIng style or ...... )
7.  New Sprockets. 

I figure on getting all the non engine stuff done first because I don't know what it's going to take to get the engine going.  I have turned the engine with the kick starter and it seems like nothing is stuck.
Any advice on what I should do in terms of planning for engine work would definitely be appreciated.  I figure once I get all the non engine stuff done, I will start with the oil system, check the compression and go from there???
Also, I am on no particular time schedule, so I plan to take my time and hopefully bring it back pretty much stock condition.
I'm not into racing, but do enjoy a decent level of performance.

Thanks,
Charlie

[edwardmorris]

Looks like a good plan, few things you may wanna consider

Grab a copy of Hondaman's book if you haven't already. Also have the factory manual printed and available at all times.

If you're replacing wheel bearings, go with SKFs if possible, pricey but permanent. I just put mine in last week. In fact, I've replaced every single bearing with an SKF one, even that pesky needle rollers in the primary drive (except for the non standard steering stem ones).

Instead of attempting to change the swingarm bushings, consider having it rebuilt by Hondaman. You can do it of course, at least consult with him first.

Me, I went with a total tear down and gradual rebuild plan, but your plan seems good too, get the non engine stuff sorted out and then focus entirely on the engine when ready.

Just my 2c of course.

[dhall57]

Don't think just because your K6 has been sitting for 26 years its going to need engine work Charlie. More times than not after a complete tune up these old Honda's will start and run with no problem. The best advice I can give you or any new member to this forum is * If it ain't broke don't fix it*

[Stev-o]

Don't think just because your K6 has been sitting for 26 years its going to need engine work Charlie. More times than not after a complete tune up these old Honda's will start and run with no problem.

+1.  Put rebuild carburetors and 3000 mile tune up on your list

[oldhatt45]

Edward,
Thanks for the advice on the bearings.  I've read your entire Ice Cream thread and picked up a lot of GOOD Info,  Nice Job on your K2 so  far.  I've been thinking bout Hondaman's book for a while and have been printing out the manual in pieces already as well as the parts manual.  Don't have quite as much wall space in my garage as you but wish I did.    Will have to contact Hondaman about the swingarm (and book).  Would like to talk to you about the bearings if you have time (LOL). 

dhall57,
That is and has been kind of rolling around in the back of my head.  I figured that the Oil system is probably the one thing I don't want to skimp on and will make sure it's good.  I also figured that the compression test will tell me whether I need to do any more work right now on the engine.  The K6 has about 24,000 miles on it, so from reading various threads, I got the impression that the mileage was around the time when many people seem to do at least some top end work, but I guess I won't know until I get to the engine part.  Also, I haven't had time to go looking for my old pictures, but I haven't forgotten.

Stev-o,
Definitely Rebuild carburetors and Tune Up.  Forgot to put on the list last night.  Any particular rebuild kit you would recommend?  Also forgot to add new fuel lines as well.  I'm wondering about the 2 big oil lines from the Oil tank.  Since they are steel braided lines???  Thanks for reminding me about the Carbs!

Also plan to go through the whole electrical system and make sure all the connectors aren't corroded and no brittle wiring and that all electrical parts work.  Also need to recover the seat since the seam on the right side has split.  Any recommendations on a new seat cover or should I rebuild the whole seat???

I appreciate the help and advice.
Thanks Again,
Charlie

[Stev-o]

24K miles on these is nothing, they've been known to go 100K without a rebuild [as long as oil is changed and no major abuse]

The last carb kits I used was K&L, just don't use Keysters, many complaints on this forum about them. If you stick with Japanese parts, you'll be fine.

I've recovered a few seats, this guy makes a nice one and is very reasonable...

http://www.ebay.com/itm/HONDA-CB750K-Seat-Cover-Four-1972-1973-1974-1975-1976-K2-K6-CB750-W-EF-/161325784623?pt=Motorcycles_Parts_Accessories&hash=item258fc41e2f

The one off my 550 that I recently did...

[edwardmorris]

Edward,
Thanks for the advice on the bearings.  I've read your entire Ice Cream thread and picked up a lot of GOOD Info,  Nice Job on your K2 so  far.  I've been thinking bout Hondaman's book for a while and have been printing out the manual in pieces already as well as the parts manual.  Don't have quite as much wall space in my garage as you but wish I did.    Will have to contact Hondaman about the swingarm (and book).  Would like to talk to you about the bearings if you have time (LOL). 

Thanks! and that wallpaper set up is in my basement, I wish my garage was as big as my basement lol. Happy to help where I can.

For the engine, like dhal said, rebuild may not be necessary and is solely dependent on what your plan is with the bike. Mine started with a wish to just get it running, and this was a bike that the PO claimed was on the road the previous season. However, every time I looked at it or posted here, I kept finding something wrong with it, so much so, that eventually it turned into a full blown frame up resto. If you're the only owner and know it well enough, you might be able to get it on the road without an engine rebuild.

Me, I'm a compulsive freak, and want everything done right and perfect, so definitely question my suggestions and advice every time.

[dhall57]

Everybody is different Charlie. Me I just fix and replace whats needed on these bikes and nothing more, give them a good cleaning and put them on the road. They aren't show bikes by no means just nice every day riders that Im not afraid to ride about anywhere and that's how I like them. IMO I like these bikes to be a little rough around the edges. After all most were built 40 years or so ago anyway. Other members like to redo everything right down to the last nut and bolt and if that's your thing then that's ok to. Yeah looking forward to seeing some of your old pics. We like pics on this forum Still think its fascinating your the one and only owner of this K6 and even though it was parked for all those years you were determined to hold on to it. I know now you are glad you did

[oldhatt45]

Stev-o,
Will go look at the K&L carb kits.  Thanks.  As far as the seat goes, I'd like to get something that looks pretty much original.  The one you referenced looks real nice, but doesn't look like original for a K6    Do you know if he makes one that looks stock?

Edward,
My goal for my K6 is to get it back looking and running when I first bought it.  Don't know if I said it, but I live in New Jersey and when I bought the K6, I would ride it to work from March through December.  Reliable as the day is long.  I would like to be able (not that I will) to go into the garage and climb on and go and not worry if she'll get me home.  Also, while I would love to be able to ride it this before the end of this season, it really doesn't matter.  So in short, I will go through it and rebuild what needs rebuilding to get her squared away.


dhall57,
Yup, I understand.  Everyone is different.    I lean toward the Edward end of the spectrum, but I'm not looking for a show piece.  Just looking to get her to the point where when I pull in somewhere, and people look at the K6 (or my 95 GTP) they kind of take a second look and smile.  The K6 is definitely one of those "I'm not letting this go" deals.  Same with my 1995 Grand Prix GTP.  I would have kept my 1984 TranAm but my daughter kind of ended that dream. 

-------------

Haven't had any time the last couple of days.  Had to do Front Brakes on my Honda CR-V (4 wheeler).  LOL  And had a couple of other things come up, but have gotten all the polishing supplies I didn't have.  Will be picking up my Fender, headlamp ears, gauge cases and case guards tomorrow and will post some pictures.  Hope to finish the 1200 grit sanding of the left fork leg on Saturday.  Then get into the polishing and buffing.

[oldhatt45]

Yesterday I picked up my Front Fender. Stays, Gauge Cases, Case Guards and Headlamp Ears.
Here is a before and after picture of the Gauge Cases.
They were in Pretty Rough Shape and I didn't think they would come back anywhere near what the y look like now.
There are pits, but I would suspect that to get those pits out would probably have left holes.  Anyhow, they look good enough now and will do until some point in the future when I can go looking for better ones.

[oldhatt45]

Then the Case Guards.  A lot better. 

[oldhatt45]

The Headlamp Ears.

[oldhatt45]

And  the Fender.  Also a picture of the before of the fender stay.
Just for reference.

[oldhatt45]

Finished the 1200 grit on the second fork leg today and will hopefully start the polishing and buffing tomorrow.
Will post some pictures tomorrow of the fork legs.

[oldhatt45]

OK, so I promised pictures of how the polishing of the fork legs is coming.
The first picture shows the leg on the left after being polished with the Red (Medium) compound and the Leg on the right at 1200 grit.
The second picture shows the Leg on the Left polished with the Red compound and the Green (Stainless grit?) compound on the right. 
Don't know if this makes any difference, but I did the Red Compound using a Spiral Sewn Wheel and did the Green Compound using a Ventilated Wheel.  That seems to be what the Eastwood brochure says to use.

The Green leg actually looks a bit more dull than the Red Leg.  Will see what happens when I do them with the Jewelers Rouge tomorrow.
If anyone has any ideas or suggestions, I'd definitely appreciate hearing them.

And Just as an FYI.  My memory of what the forks looked like when I bought the K6 seems to be more like the 1200 grit sanded leg in overall shine and brilliance.  But we're talking about 38 years ago, so..........

[oldhatt45]

Found out something very interesting today.
I went back over the fork leg that I did with the Green/Stainless compound yesterday.
Only this time instead of using a ventilated polishing wheel, I used a spiral sewn wheel.  Looks like I got somewhere!  It now looks better than the Red Compounded leg.
Will add some pictures later on.

[edwardmorris]

Good work, keep it going.

I do notice that they look a bit too shiny to be stock, but that's expected. Its very hard to get that factory look, because they were working with freshly molded aluminum that already looked great without all the sanding. Look into this thread http://forums.sohc4.net/index.php?topic=79183.540;

Mark dialed down the extra shine by using some gray scotchbrite, then clear coated them with a nice hands-free set up.

[oldhatt45]

Edward,
Thanks for that info!
Not sure if I'm going to try the Scotch-Brite trick.  After spending this much time I'm kind of waffling.  LOL
But it is good info.  Keep it coming.
Thanks,
Charlie