Topic: 1976 CB550 K2 First timer - Sold

[SOHC4 Cafe Racer Fan]

I'm going to give flickr.com a try.  I hope Photobucket's stock value takes a dump.  I noticed they were inundating the pages with pop up ads, so they were already monetizing the site.  This move is going to piss off users enough to leave their service.  Then the ads won't be worth a damn.

[mscuiletti]

Well, I obviously have not fixed any of my links, so I will attach the latest photo just so there is a picture in this thread.

[mscuiletti]

I was unhappy with the smoothness of the hoop and welds, so spent some time cleaning them up. I need to bend the pan again to follow the curve of the frame, as the gap beneath the seat bugs me.

[SOHC4 Cafe Racer Fan]

The very slight curve of the seat rails on the 500/550 can be a little bit of a pain.  The Motolanna/Dime City seats fit better because they have some curvature.

image_zpsdfilcfz7 by Donald Leonhardt, on Flickr

CognitoMoto_10_zps08cafwoo by Donald Leonhardt, on Flickr

You can also cut and weld new flat frame rails, but that's a bigger pain.

Alternatively, if you seat has some overhang (below the rails) it can simply hide any small gap.

[mscuiletti]

The very slight curve of the seat rails on the 500/550 can be a little bit of a pain.  The Motolanna/Dime City seats fit better because they have some curvature.

The pan was made from metal and had been curved to follow the rails, but I think as the upholsterer wrapped it, the pan straightened. I have been slowly bending it back and it looks much better now.

[SOHC4 Cafe Racer Fan]

The very slight curve of the seat rails on the 500/550 can be a little bit of a pain.  The Motolanna/Dime City seats fit better because they have some curvature.

The pan was made from metal and had been curved to follow the rails, but I think as the upholsterer wrapped it, the pan straightened. I have been slowly bending it back and it looks much better now.

Great.
Slow and gentle so as to not pull out the upholstery staples or glue.

[mscuiletti]

I finally got around to installing new control cables and the master cylinder. I spent quite a bit of time attempting to vacuum bleed the system yesterday and have been pulling a lot of air, but the fluid is just barely dropping in the reservoir. I pulled the top line from the brake assembly to put my finger over the hole while pumping the lever, and although brake fluid oozes, there is no pressure to push my finger away. Should I feel more pressure? I bought the master cylinder "in working condition"...

[mscuiletti]

Bled with zero issues once i replaced the brake line with a single ss line and new pressure switch. However, now the caliper is locked, so I ordered a new seal and will be rebuilding that. Probably all things that I should have done anyways.

[calj737]

Check the pads themselves. Often the edge of the pad is painted is just a few hairs too large to retract smoothly. The cure is to gently sand off the paint, and that allows it to move freely.

[mscuiletti]

Check the pads themselves. Often the edge of the pad is painted is just a few hairs too large to retract smoothly. The cure is to gently sand off the paint, and that allows it to move freely.

You have such a plethora of helpful information. I will try that as well, but would you recommend replacing the pads as well? They have a ton of material but I am unsure of the age...

[calj737]

I would only replace them if they are unevenly worn or are nearing the wear limit. If they are not new, then the retraction problem is not likely the issue. Possibly a blocked return port in the reservoir.

[Godffery]

 My money is on this:  (I bought the master cylinder "in working condition"...)
Likely a bit of blockage in the tiny return port.

[RAFster122s]

Never hurts to upgrade the brake hose to Teflon stainless steel braided lines for a no expansion brake line. It will give you solid feedback and the old lines if original have done their job.
A remote possibility that the internals of the lines are failing causing the lines to act like a one way valve.  Clean the tiny hole in the master cylinder with a very small stiff wire and your probably going to have working brakes. Disassembling the caliper (pulling piston) and replacing the seal with a new seal and cleaning the groove is good maintenance. Replacing seal maybe every 8-10 years or as needed. Use good clean fluid, I like Castrol GTLMA but it is hard to find these days.  Not as many places carrying it.  Brake fluid draws water, so it needs to be completely drained/flushed/bled in your brake to purge the old fluid and replaced with clean new fluid a minimum every 2 years.  Using a freshly opened container is recommended so you know it has not been drawing moisture into the container, even with a cap on it it will have water making its way into the fluid.  Water in your brake system can boil causing major issues as well as cause rusting or oxidation of aluminum and other metals.

But, if you can get your master cylinder bled as it sounds like it has a blockage as others have pointed to the small , and we do mean tiny, hole in the Master Cylinder that gets blocked with a tiny piece of debris.

Start with the inexpensive and move to more expensive rather than throwing money at a problem...far cheaper in the long run.

David

[mscuiletti]

Never hurts to upgrade the brake hose to Teflon stainless steel braided lines for a no expansion brake line. It will give you solid feedback and the old lines if original have done their job.

I mentioned earlier that I had replaced the line which resolved the bleeding. I was unsure of the routing so if anyone has a suggestion. I ran it on the outside of the fork.
20171026_163026 by marc_scuiletti, on Flickr

Here is the new pressure switch:
20171026_163038 by marc_scuiletti, on Flickr

My messy garage:
20171026_163108 by marc_scuiletti, on Flickr

The caliper had lots of crud built up, so I will spend some time cleaning it, installing the new seal, and will install the new pads once they arrive (just ordered):
20171105_154825 by marc_scuiletti, on Flickr

[calj737]

Stock brake line ran inside of fork leg, had a longer hard line from caliper to keep the line stable, and was retained with a plastic grommet in the fender. Without the fender, Juilliard need to fabricate something to hold the line away from the tire.

[RAFster122s]

Heard of a guy or two who ran without fender and had an over the tire line to second caliper and didn't think he was at risk for any damage.  Until his tire caught the line and in the blink of the eye it ripped the hose off and instant no front brakes.
Old fender mount M6 bolt holes can be used to attach a wire or metal tab for your line holder, was going to call it a hose holder, but figured some smart fellow would play with those words.

[RAFster122s]

Brass will not damage the aluminum, if you have a dremel tool a brass brush in the dremel can clean the slot for the seal very well and fairly quick.  TwoTired has an excellent writeup about how to properly rebuild, refresh your brakes, it should be in the brakes FAQ on the site.
Red rubber grease and Dow High Vacuum Petcock grease, a silicone grease that will not melt and migrate to your pad surface, are highly recommended for your brake system.  The seal gets the red rubber grease or brake assembly lube while the pad back and edges and pivot pin for the caliper mount arm get the silicone grease.
The silicone cannot come in contact with the brake fluid or it contaminates the fluid and would have to be changed.

[mscuiletti]

I picked up some grease and a brash dremel attachment this morning and got back to the caliper. After some cleaning, installing the new seal and pads, and bleeding again, I have working front brakes. Progress!!!   

I had used brake cleaner to get some of the crud out, but went at it with a brass dremel attachment as suggested.

20171118_141938 by marc_scuiletti, on Flickr

After some cleaning

20171118_143537 by marc_scuiletti, on Flickr

Installed again, minus fabricating a mount to hold the brake line away from the tire.

20171118_150442 by marc_scuiletti, on Flickr

[mscuiletti]

Pulled the carbs just to shoot some cleaner and everything is opening and closing. I adjusted the throttle cables to remove most of the slack, however, the assembly does not rest against the pin. I had bench synced the carbs so there is a slight gap still, could that be why? Is this an issue? *Note: the photo was taken before i took slack out of the cable*

20171125_111610 by marc_scuiletti, on Flickr

You can see where the upholster got a bit crooked at the rear of the seat. It will be dropped though so I did not bother having them try again. It was great pushing the bike around and using the brakes.

20171125_120150 by marc_scuiletti, on Flickr

[mscuiletti]

To restore the luster of your tank, you can simply wet sand it (lightly, use 1200 grit, then 2,000) and only the top of it. The Black is a single stage paint, the color is multi. The use a quality foam pad to buff it out. You can follow-up with the nano-ceramic coating Marissa recommends for tremendous protection (UV and Chemical). The only trick about the nano coating is the taped on stripes. 

The badges you can restore with some Testers Model paint and shoot some rattle can clear over them.

Took your advice and spent some time sanding and polishing the tank. I like the faded top and scratches. As this is not a restoration, I think it turned out great.

Here was the state of the tank:
20171218_113955 by marc_scuiletti, on Flickr

After sanding:
20171218_115046 by marc_scuiletti, on Flickr

After polish:
20171218_122839 by marc_scuiletti, on Flickr

Installed the new trim and started work on the emblems. I'll sand down the white to a smooth finish and try my unsteady hand and painting the gold and black. Even my small brushes are too large for some of the gaps, so I am hoping a toothpick works. Any suggestions here?:
20171219_181351 by marc_scuiletti, on Flickr

[calj737]

Turned out great! Next time, pry the badges off and paint them free of the tank. Much easier 

[mscuiletti]

Turned out great! Next time, pry the badges off and paint them free of the tank. Much easier 

You know I had thought about that but was sure that I would end up breaking them. Next time!

[mscuiletti]

I have most of the slack out of my throttle cables (the pic is from before I removed the slack), but when i open the throttle and close it, the cables still seem loose, and i worry the push cable will disconnect. I used a 1/8 drill bit (i think) to bench sync and set the position of the slides. Now however, the bracket that the throttle cables rotate does not rest against the stop. If i were to loosen that, i could get more adjustment out of the cables to tighten them up. My question is, should this throttle assembly stop against that pin, allowing more adjustment? Here is an older photo before i got most of the slack out of the cable:



Thanks for any advice you can offer and sorry if this had been covered. I read a few throttle adjustment posts and it seems like this doesnt need to stop against the rest...

-Marc

[mscuiletti]

I have been doing a lot of research and nearly went with a Hindle system, but I love the look, reviews, and sound of the MotoGP Werks. I have been in communication with them and have my name on one for end of January. Fingers crossed he doesn't get too busy or anything. It seems that the quality is top notch for the price, so I am looking to seeing the craftsmanship.

[Stev-o]

...but I love the look, reviews, and sound of the MotoGP Werks.

I do too!  I installed one on my K3...






You will not be disappointed.