Topic: 1977 CB750 K7 Resto-mod, Knoxville

[AintNoEasyWay]

Hey guys, I'm starting a project thread for my K7 because it'll be a hell of a lot easier to ask questions/get opinions here rather than continually throw up questions in the SOHC bikes part of the forum.

A little back story: so this is my first bike (first picture below). I bought it last year after reading a little about bikes & finding this forum. I had zero mechanical experience at that time. The bike is in decent aesthetic condition because it's been garage kept, but the PO went to work overseas for 3 years & left fuel in the tank & carbs & brake fluid in the master cylinder body. It wasn't running when I bought it. Everything was stock except the 4 into 1 exhaust.

Fast forward to this past weekend. I've rebuilt the carbs completely (Keihin PD41as). Changed from points to PAMCO ignition. De-rusted the fuel tank. Replaced air filter. Changed oil. Bike started up first thing this weekend, & after syncing the carbs & getting over a brief hiccup in fast idle cam adjustment, the bike idles steadily at about 1100 & fast idles at ~2750.

So before doing a test ride I still have the issue with the master cylinder. I've ordered a rebuild kit, new piston seal, & new brake pads. I'm not sure if I'll need more than that to get everything set up properly. I haven't checked the degree of damage to the front brake, but I'm pretty sure it's frozen up because I can hardly squeeze the front brake lever.

After I solve the front brake issue, I'll go on to do a 3k tune up, & hopefully be able to do a test ride.

If everything goes according to plan, I'll move on to more aesthetic upgrades. I'd like to keep the original look of the bike, but slim it down some. Something along the lines of the second photo below. I would really look to have a shorter rear fender, for one. I'll of course need to have my seat reupholstered. Change out turn signals, rear light, & probably mirrors. Probably remove my center stand. & get a paint job & some side cover emblems.

Thanks to anyone that chimes in along the way. Have basically learned everything from this forum alone.

[flybox1]

Even though its running and sounds good, dont forget the rest of the 3k maint items. 
Vac sync of the carbs always comes last.
Be sure to closely look over your brake piston. 
Excess pitting can prevent it from sealing and properly retracting.....

[AintNoEasyWay]

Cool. Thanks, flybox. I was wondering if I'd need to resync now that the fast idle is set up. I thought I read in my Clymer that the fast idle adjustment was the last thing, but that doesn't make sense now that I consider it. Want to be sure & do everything properly before I move on to anything else.

[flybox1]

I was wondering if I'd need to resync now that the fast idle is set up.

resync? probably not necessary, but, once you get your valve lash set (unless you did it and i missed that post) you should do it again.
a sync is easy and only takes a few minutes.  never hurts to do it again, but be sure its on a hot engine....

[AintNoEasyWay]

Haven't adjusted the valves yet. Looking at the shop manual I think all I've got left to do is valve check, cam chain check, & compression test.

I forgot to add that I've got a new battery in the bike & new high output coils/spark plugs, so much of the tune up is already done. Tires are also pretty new. Front tire has about 300 miles on it according to PO, rear tire is brand new.

[enwri]

Nice choice of bike,
My 77 isn't pretty but I could never sell it now, had it a long time.
We can ride all year round here, coldest I've ever been is 0 degrees Celsius, it's been through tropical storms, searing heat, dirt roads and miles of bush tracks, mud, lots of mud (worked in a quarry, you can't turn around in the tyre track of a 50 ton dump truck, have to follow it to the hard ground.) and has run like a Swiss watch the whole time. Batteries die every few years, kickstarter is very handy.
It regularly ended up on it's side after that little foot on the sidestand punched through the hot bitumen, but it always started, the ignition switch has melted twice, headlight always on here. They're easy to hotwire, so I've never been stranded, lucky the steering lock is harder to get around.
90kph in first gear, 2400 at 60kph, 4500 at 100kph, it will do it forever.
Have fun with it, it's a good thing.

[AintNoEasyWay]

Very cool, enwri! Enjoyed reading about everything your bike has been through. Also just had to look up what "bitumen" was. Haha!

I'm bummed though because I realize I made the goofy mistake of posting this "project" thread up in the SOHC Bikes part of the forum.  Must have had windows for SOHC Bikes & Project Shop both open at the same time. Should I move my original post on over to the project shop & let this thread die out?

[lucky]

Haven't adjusted the valves yet. Looking at the shop manual I think all I've got left to do is valve check, cam chain check, & compression test.

I forgot to add that I've got a new battery in the bike & new high output coils/spark plugs, so much of the tune up is already done. Tires are also pretty new. Front tire has about 300 miles on it according to PO, rear tire is brand new.

Make sure to take the slack out of the cam chain BEFORE you adjust the valves and do it by the book.  The crankshaft does need to be in the correct position to take the slack out of the cam chain. See the photo in the Clymer's workshop manual.

[martin99]

Very cool, enwri! Enjoyed reading about everything your bike has been through. Also just had to look up what "bitumen" was. Haha!

I'm bummed though because I realize I made the goofy mistake of posting this "project" thread up in the SOHC Bikes part of the forum.  Must have had windows for SOHC Bikes & Project Shop both open at the same time. Should I move my original post on over to the project shop & let this thread die out?

I'm sure one of our clever moderators could move the whole thing over for you, if you can work out how to get hold of them

[AintNoEasyWay]

Very cool, enwri! Enjoyed reading about everything your bike has been through. Also just had to look up what "bitumen" was. Haha!

I'm bummed though because I realize I made the goofy mistake of posting this "project" thread up in the SOHC Bikes part of the forum.  Must have had windows for SOHC Bikes & Project Shop both open at the same time. Should I move my original post on over to the project shop & let this thread die out?

I'm sure one of our clever moderators could move the whole thing over for you, if you can work out how to get hold of them

Damn. I've never seen a moderator around here, but that's a good idea.

EDIT: Nevermind. Bob Wessner helped me out. Thanks, Bob!

[SOHC4 Cafe Racer Fan]

That's a solid-looking K7. 

I previously bobbed my K7 rear fender.  Pretty easy to do -- just trim the fender from the inside leading edge, and drill new mount points.  You will likely want a new taillight to match the slimmer profile.  Depending on your taste, you may also think about Euro-spec bars or CB400 handlebars that do not rise like the stock K7 (apehanger-esque) bars.  Smaller signals are tasteful, too. 

Safety-wise, you should also look into replacing your brake lines with braided stainless steel lines, and replacing your steering ball bearings with tapered/sealed roller bearings, and replacing your wheel bearings and the swingarm bushings.

Looking forward to seeing your improvements.

[AintNoEasyWay]

I ordered parts today to rebuild my master cylinder. Also purchased new brake pads. I don't think the shipment will arrive until next week so I'm thinking about taking time to polish up some parts this weekend. I've never done this before so have been searching for best methods. It seems like working up with sandpaper is common technique. Does anyone use a buffer/dremel tool? Is it necessary to remove the clear coat, then have it coated back after? Would also love to get ideas on general rust removal. My right front fork has some rust that I'd like to remove; hoping to cover my forks with gaiters but would like to remove this rust first. I'll post a picture later on.

That's a solid-looking K7. 

I previously bobbed my K7 rear fender.  Pretty easy to do -- just trim the fender from the inside leading edge, and drill new mount points.  You will likely want a new taillight to match the slimmer profile.  Depending on your taste, you may also think about Euro-spec bars or CB400 handlebars that do not rise like the stock K7 (apehanger-esque) bars.  Smaller signals are tasteful, too. 

Safety-wise, you should also look into replacing your brake lines with braided stainless steel lines, and replacing your steering ball bearings with tapered/sealed roller bearings, and replacing your wheel bearings and the swingarm bushings.

Looking forward to seeing your improvements.

Thanks, fan. Do you happen to have any photos of your K7?. Nevermind, found it in your sig. Awesome! Would be great to see that look of the shorter rear fender on actual K7. What CB is pictured in the second photo above? It seems like the seat is already much shorter than mine; I'm wondering if this might make it look weird if I try to replicate the shorter fender on my bike if I keep the longer, original seat? I'm also planning to change out for bars more like those in the picture above & like you've mentioned. Should I just search for CB400 handlebars or is there a specific name for that style of bar?

I've already been taking a look at different turn signal/rear brake light options. I'm definitely planning to do as you recommend & get something smaller to go with the slimmed down profile. 

Replacing bearings & bushing is also a very good idea. That may be a project I set out to complete sometime over summer before I do any serious riding. Right now, I'd just like to get the bike out on the road & test things out. Thanks again for your input!

[SOHC4 Cafe Racer Fan]

The second bike above in your fist post is somewhere between a K2-K6. The font and rear fenders have been bobbed. He's also using bars similar to CB400 or Eurospec bars with a lower rise.

[AintNoEasyWay]

Cool. So either start looking for a CB400 bar or maybe something along these lines?: http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-handlebar-parts-satin-black-euro-bars-11-0530-s.html

potentially with these mirrors: http://www.dimecitycycles.com/vintage-caferacer-cafe-racer-bobber-chopper-brat-custom-motorcycle-handlebar-parts-black-british-triumph-baron-bar-end-mirror-ap-104b.html

[SOHC4 Cafe Racer Fan]

Cool. So either start looking for a CB400 bar or maybe something along these lines?: http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-handlebar-parts-satin-black-euro-bars-11-0530-s.html

potentially with these mirrors: http://www.dimecitycycles.com/vintage-caferacer-cafe-racer-bobber-chopper-brat-custom-motorcycle-handlebar-parts-black-british-triumph-baron-bar-end-mirror-ap-104b.html

The Dime City bars are a pretty good match and decent price. 

[AintNoEasyWay]

Cool. I read several threads on the Euro spec handlebars today. Love the look of these & they seem to get a lot of love on the forums as well. Is this something I have to buy shorter cables for, or will everything work as is?

 I'm considering going with these grips: http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-handlebar-parts-black-billet-retro-race-grips-bar-ends-r1-211-bk.html

Would prefer to just go ahead & order handlebars, grips, mirrors all together to avoid unnecessary shipping costs. My only worry is: how do I know all this is compatible? I'm most impressed by the guys on here that are sourcing parts from all different places & manage to get everything to fit. It's pretty crazy to watch some project threads & see guys have their visions come to fruition. Very respectable, I think.

[SOHC4 Cafe Racer Fan]

Cool. I read several threads on the Euro spec handlebars today. Love the look of these & they seem to get a lot of love on the forums as well. Is this something I have to buy shorter cables for, or will everything work as is?

 I'm considering going with these grips: http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-handlebar-parts-black-billet-retro-race-grips-bar-ends-r1-211-bk.html

Would prefer to just go ahead & order handlebars, grips, mirrors all together to avoid unnecessary shipping costs. My only worry is: how do I know all this is compatible? I'm most impressed by the guys on here that are sourcing parts from all different places & manage to get everything to fit. It's pretty crazy to watch some project threads & see guys have their visions come to fruition. Very respectable, I think.

Those billet grips will get awfully uncomfortable awfully quickly.  Also they would not likely be compatible since the cap has to screw into the grips and you will have a bar end mirrir separating the two pieces. 

I would suggest getting a conventional pair of comfortable grips and bar end mirrors with built-in end caps.

You should be able to use your stock cables with Eurospec bars.  The cables might be slightly longer but should not create issues.

[AintNoEasyWay]

Ok, good to know. So I can stick with those original mirrors I posted but need to be looking for grips with open ends. Correct?

[SOHC4 Cafe Racer Fan]

Ok, good to know. So I can stick with those original mirrors I posted but need to be looking for grips with open ends. Correct?

Yes. Or if they are rubber, you slice off the end.

[AintNoEasyWay]

Safety-wise, you should also look into replacing your brake lines with braided stainless steel lines, and replacing your steering ball bearings with tapered/sealed roller bearings, and replacing your wheel bearings and the swingarm bushings.

I found some nice stainless steel brake hoses here: http://slingshot-cycles.com/. Do you guys have recommendations for where to grab new, upgraded wheel & steering bearings & swing arm bushings?

[SOHC4 Cafe Racer Fan]

Safety-wise, you should also look into replacing your brake lines with braided stainless steel lines, and replacing your steering ball bearings with tapered/sealed roller bearings, and replacing your wheel bearings and the swingarm bushings.

I found some nice stainless steel brake hoses here: http://slingshot-cycles.com/. Do you guys have recommendations for where to grab new, upgraded wheel & steering bearings & swing arm bushings?

Slingshot give us members a discount code SOHC4.  All Balls Racing is a good source for the tapered roller bearings for the stearing stem and wheels.  For swingarm bushings, I thought there was someone on the forum selling them, but I can't remember.  You want to find brass ones -- they are readily available on ebay.

[flybox1]

Safety-wise, you should also look into replacing your brake lines with braided stainless steel lines, and replacing your steering ball bearings with tapered/sealed roller bearings, and replacing your wheel bearings and the swingarm bushings.

I found some nice stainless steel brake hoses here: http://slingshot-cycles.com/. Do you guys have recommendations for where to grab new, upgraded wheel & steering bearings & swing arm bushings?

SLINGSHOT is great for SS lines.  Iv'e had them on both my CB's.
Get your wheel and steering bearing kits from All Balls.
Hondaman rebuilds swing arms.

[AintNoEasyWay]

Awesome. Thanks, guys.

Flybox, I found & read through your '78 build thread earlier today while looking for tips on how to paint my gas tank. Really enjoyed it!

[AintNoEasyWay]

Checked valves & adjusted the cam chain today. Only the 3rd cylinder intake calve needed adjustment, everything else was in good order.

I adjusted the cam chain first & then did the valves. When adjusting the cam chain, all I did was line up the crank shaft 15 degrees past TDC & undo the bolt & screw to adjust. I never heard any sound or anything like that. I didn't know how to confirm it adjusted or pick up any slack in the chain. Maybe there wasn't any?

Other than that, I'm still waiting on parts to rebuild my front brakes. Also placing an order tonight for new euro handlebars, bar end mirrors, & grips. Waiting for parts is tough!

[AintNoEasyWay]

Hey guys, I'm looking for new side cover emblems for my bike & found these: http://4into1.com/honda-cb750k-black-unfinished-side-cover-emblem-1977/

Do you guys have any experience with these or have you read of anyone else trying them out? Also any recommendations for what to use to paint them?