Topic: Getting 750K up and running

[zabzob]

I've just picked up a '75 CB 750K in great (cosmetic) condition. It hasn't been on the road since 1995, so I know I have quite a bit of work ahead of me. I have the Clymer manual, and some experience getting an '82 Yamaha XJ 650 Maxim all fixed up a couple of years ago. That was carb rebuilds, balancing, and a lot of electrical work. Here's my list for things I have to do for the CB so far:

Replacing:

• Oil filter
• Air filter
• Plugs
• Ignition wires, most likely
• Clutch/throttle cables
• Master cylinder leaked all over, rebuilding to be on the safe side
• Caliper rebuild
• Chain
• Sprockets
• Clutch
• Carb rebuild
• New fuel lines + inline filter
• New wiring harness was $75 at partsnmore.com, so I went for it. I hate electrical problems.
• Clean/dielectric grease all electrical connections
• Sealed fuse box and blade type fuses
• Fork oil

Tank is not rusty, and the inline filter should take care of what I can't see.

Bike has electronic ignition.

I have questions about brake pads/shoes. The mileage on them is unknown. Should they be replaced anyway, just due to age?

I've bought the clutch friction plates and springs, but I'm not sure about the steel clutch plates. The previous owner related a story about how he had a bike that hadn't run in a while, and the clutch felt fine... but after 500 miles, the plates had basically disintegrated and he had no friction. Should I replace them to be on the safe side?

Tires, mileage unknown. They hold air and have no cracks that I can see, but is a tire that old safe?

Wheel bearings. Again, mileage unknown. Probably better to replace, but it doesn't look all that easy for the rear wheel, and with all the stuff I have to do already... I'm afraid I'll take this thing apart and get stuck on a few bits and pieces and then I won't get it all back together until mid-June.

I am resisting the urge to replace the rusty back spokes "while I'm in there" because I can see aligning the wheel being a second-guessing-myself nightmare.

Cam chain. Bike has 28,000 miles, and it's never been replaced. I hear the replacement time is 30,000 miles and and I don't expect I'll put all that many miles on it this summer. Something that can wait, or should I do it now?

I think that's all. The plan of attack is to get the carbs rebuilt and fire it up first. The back brake works, so I'll be able to ride it around a parking lot at low speeds. After that electrical, then all the roadworthy stuff. Trying not to change too many variables at once.

Anything else I should be doing, or other advice?

[ekpent]

Welcome aboard.Might need some fork seals also,when you drain the oil look for water or major discoloration of oil to see. Also plug wires you mentioned,unless you splice are a pain to replace,have to cut and drill etc.If wires look good just check out the caps.When you "rebuild" your carbs just start off cleaning the hopefully stock stuff that's in there and just get a gasket if needed for starters,stock is better.Inline fuel filters can sometimes be problematic.Go with a nice clean tank and petcock filter. Give her a real good tune up,check the points etc well and with the rest of your objectives you should be in good shape. Now the most important thing is WE WANT PICS    PS-I have never heard of the 30,000 cam chain rule.

[Johnie]

You have a good list there. As a rule I change all my wheel bearings just because of the age and the fact bearings are so much better these days than the early 70's. Doing it yourself makes the swap a pretty cheap fix. You may want to wait until next year if things feel good and time is not on your side. I agree with ekpent to change the fork seals and give the forks a good cleaning. Wait until you see the junk at the bottom of the tubes...you will be glad you did them. Heck, a total fork rebuild is only the seals and fluid. If those brake pads look good just rough them up with some sandpaper. Do the same with the brake drum. If my rotor gets to shiney and squeals I rough that up as well with good results. How does the steering head feel? What...no pics yet??? Welcome to the forum...

[MoMo]

+1 on the 30000 cam chain. That'd mean you would have to tear your motor down every 30k to replace the chain .  The friction plates would be a precaution, the steel rarely unless the PO was a hole shot artist.  Disassemble the clutch, clean the friction and steel and you should be good to go with what you have. On the dozen or so bikes I have done in the past 5 years I have never had to replace a clutch, all clutches  have worked well. Only problem was a Goldwing and the owner decided to sell rather than fix the clutch.

New plug caps rather than wires.  MC and caliper rebuild a must.  You can check the wheel bearings when the wheels are off, I have rarely had to replace them.  Brakes pads and shoes are a possibility, I have had shoes and caliper pads fall off . Remove the rear brake cam, clean and lube-same with the front caliper holder. I never have replaced a wire harness, only way I would do that is if the PO had mutilated it.  \

Good luck with the bike and welcome...Larry

[Skunk Stripe]

How rusty are those spokes? Is it just a light surface rust or is the pitting pretty heavy? If light surface, try cleaning them up with emery paper or steel wool.

[greenjeans]

Hello and welcome,

I'd get new tires for sure.   Just because they don't have cracks doesn't mean they'll hold together.  They're at least 16 years old...

As for the brakes - I think I'd go ahead and get new pads & shoes - if nothing else, for peace-of-mind.     My last CB project had been sitting for a very long time as well.
The pads and shoes looked fine - almost new.   After about a week of riding, the braking material separated from the shoe completely... Luckily I was only doing about 20mph when it happened and was able to skid to a controlled stop.   I've never actually seen that happen before.   From now on, I only use new pads and shoes.
Just something to consider.

Other than that, it seems like you're on the right track.    Welcome to the addiction.

[Johnie]

Good info there greenjeans...I had never heard of that happening. Agree, lucky you were not going to fast or you may have worn out the soles of your boots.   

[Prospect]

As for the brakes - I think I'd go ahead and get new pads & shoes - if nothing else, for peace-of-mind.     My last CB project had been sitting for a very long time as well.
The pads and shoes looked fine - almost new.   After about a week of riding, the braking material separated from the shoe completely... Luckily I was only doing about 20mph when it happened and was able to skid to a controlled stop.   I've never actually seen that happen before.   From now on, I only use new pads and shoes.
Just something to consider.

Other than that, it seems like you're on the right track.    Welcome to the addiction.

That happened to me too.  It's the only time I had to tow a bike home. Wheel was completely locked and wouldn't budge. Now I always change them.

[ekpent]

Have not looked in awhile but has anybody else noticed that pre 77 , 750K front pads are not as easy or cheap to find anymore on the aftermarket scene. I stocked up a little stash awhile ago when I was looking last when I found a deal.

[GammaFlat]

The pads and shoes looked fine - almost new.   After about a week of riding, the braking material separated from the shoe completely...

I had a barn find where the rear wheel was locked.  I didn't have to work very hard to get it unlocked but the brake material separated from the shoe in that case as well. 

In terms of replacing the front, you'll have problems finding new ones that don't squeal.  The non-asbestos ones are a bit of a pain in that regard. 

The date of mfg should be in the sidewall of the tire.

NGK plug cap replacement!  Yes!

[GammaFlat]

We need pictures!

[zabzob]

Pictures! Tank and side covers are in good shape with original paint. Ugly Goldwing bars have to go. Master cylinder is toast. You can see some random wires hanging off the frame in some of the shots. These used to go to the big fairing (with tape deck!) which was removed. The seat it came with is awful.

Rear spokes not looking so hot. A lot of the rust on the rims and other chrome is superficial and comes off with steel wool.

[zabzob]

Thanks for the welcome everybody!

ekpent: Good to know that I can leave the cam chain. I wasn't looking forward to doing that. Wires... right. It's been a while since I've worked on a bike, and I forgot that they are fused to the coil. New caps then. I already have the carb rebuild kits, so new gaskets are there if I need them. I can always stick with the original needles and such too. Electronic ignition... no points! Yes!  Also, the best price I've seen on front pads is at CB750 Supply. $19.00. http://www.cb750supply.com/products/2/chassis-brakes/39/brakes

Johnie: Fork seals I accidentally left off the list. I'm changing the oil, so I'll replace those and give it all a good cleaning. I'll order some new bearings when I pick up some other parts, but I might wait until November to do them if the current ones feel solid. Steering head feels okay when pushing it around the garage.

photolar: Yeah, I might leave the clutch for now and see how it feels when it's warmed up. I have the friction plates just in case, anyway. The current harness is semi-mutilated, due to the fairing that came with the bike. I'll run it as it is for this season, I think.

Skunk Stripe: Close up of the spokes there. Didn't have time steel wool 'em up tonight, just pulled off the tank and carbs.

greenjeans: Yeah, new tires it is. Hopefully they'll hold together for a trip to the tire store. 

From several stories here, sounds like new brake pads and shoes are in order. I have no desire to Flintstone stop!

[Johnie]

Ah, great pics there. That is going to look great with the planet blue back on there. Always liked that color. You have a great start and will get plenty of lookers when you are running it around.