Topic: CB750 K4 Build - The Cafe Tracer

[budman]

If have to relocate that petcock, you could buy a weld in bung, but silver solder it. Then locate and carefully drill another weld in to fit. Again solder it. Solder would generate less heat, less damage to your paint, and the liner might actually survive to the point that it would seal the soldered bung, obviating a weld/paint job.

There are numerous very low profile types if you have to cap that original location.

I found an adapter, in conjunction with an npt plug, that I could use to plug the existing bung, but I think it would drive me nuts knowing it was there.  Silver soldering sounds like it requires some skill.  I would still have to remove paint and body filler at the new bung location.  I don't think I could get a clean looking repair without having to do body work and paint.  The tank doesn't have a large flat surface on the bottom like a regular CB750 tank.

[budman]

The tank doesn't have a large flat surface on the bottom like a regular CB750 tank.

Ah. Yeah, that makes it very tricky. 

I remember an episode of American Chopper where they forgot to weld in the fuel bung and didn't discover it until after the tank was painted and the bike had to delivered.  The tank had a flat bottom and they used a hole saw to cut a ring through the paint, primer and body filler just down to the sheet metal.  Then they hand scraped the paint and filler out of the middle of the circle.  The circle was quite a bit larger than the OD of the bung flange.  They drilled a hole for the bung and carefully tig welded it in.  I think they used some wet rags on the tank to keep the surrounding paint cool while they welded the bung in place to keep it from peeling up.  Then they were able to repaint the bottom.  I think they might have painted just inside the circle.  I can't remember exactly.  I don't think they had sealed the tank either.

[mrbreeze]

Ha ha!!!.....American chopper!!! Hey Pauly....I got this idear!!!

[budman]

Ha ha!!!.....American chopper!!! Hey Pauly....I got this idear!!!

You've seen that show too?

[mrbreeze]

But of course!!...but it's been awhile. I sure hope the adaptor works out for you. I would gladly give up having reserve than to start hacking up a finished tank. Would it be possible to raise the tank a smidge to get the needed clearance?

[budman]

But of course!!...but it's been awhile. I sure hope the adaptor works out for you. I would gladly give up having reserve than to start hacking up a finished tank. Would it be possible to raise the tank a smidge to get the needed clearance?

I've been thinking about how I could gain some clearance if needed.  I could put a washer (shim) under the rear mounting point of the tank.  Maybe even shave a little bit off the outlet adapter if I had to.  I'll just have to wait for it to get here.

[budman]

The machine shop knocked out the top mounting rod so I installed it.  Looks clean.  Waiting on some new mounting bolts for the top front.

[budman]

So I talked to my buddy and got a quote for threading the stainless steel mounting rods, and I priced out the cheapest stainless steel metric round bars I could find.  It doesn't look pretty.

To make a set of three mounting rods available I would need to charge $115 a set...and I'm not making a lot of money per set.  That price doesn't include the hardware either.  The price per thread isn't cheap and neither is the price per foot for the round bar, plus shipping.

If it sounds like a lot of money, I completely agree.  I've got that much in the rods I made for myself.  I paid too much for the round bar in the first place and while I didn't pay my buddy for the threading I did tip his shop foreman and the machinist who did the work, handsomely.

I doubt I'll get any takers at that price and to be honest I would need to get at least 10 orders to make it worth my while.  I'm just too busy to do a few sets.  Sorry I couldn't do better.

[budman]

I've made them too. They are a work of love and if you charge just $50/Hr., they would run about $200 the way I make them.

I've used 303, 304, 316L and even 416. Have even welded a nut onto one end, then faced it in the lathe to make it look original (thats a $200 bolt by shop rates). But they do look sexy when they're made up...

I think the entire process of restoring and customizing motorcycles is a work of love.

[SOHC4 Cafe Racer Fan]

I've made them too. They are a work of love and if you charge just $50/Hr., they would run about $200 the way I make them.

I've used 303, 304, 316L and even 416. Have even welded a nut onto one end, then faced it in the lathe to make it look original (thats a $200 bolt by shop rates). But they do look sexy when they're made up...

I think the entire process of restoring and customizing motorcycles is a work of love.

Three parts love, one part frustration/pain.

[budman]

Three parts love, one part frustration/pain.

Yes, I think your statement is more accurate than mine.

[edwardmorris]

I've made them too. They are a work of love and if you charge just $50/Hr., they would run about $200 the way I make them.

I've used 303, 304, 316L and even 416. Have even welded a nut onto one end, then faced it in the lathe to make it look original (thats a $200 bolt by shop rates). But they do look sexy when they're made up...

Calfab (as in fabricated by Cal) hangers 

[budman]

Sweet!

[budman]

Well, this ain't gonna work.  There isn't enough room.  I bought that outlet adapter, whittled on it in the lathe and it's just too big.  I've got about 1/4" clearance on the short side and it just isn't enough room.  Looks like I'm going to have to make some sparks.

Also my forks started leaking.  I pulled the front wheel off and used a 3/8" impact to put a little more crush on those crush washers up inside the bottom of the fork.  Hope that does it.

Think I'm going to stop for the day.  Off to order a new gas tank bung.

[budman]

I've been on vacation all last week, but before I left I did manage to plug the old bung in the gas tank and weld in a new one that is in front of the engine where their is plenty of room for a petcock.  I re-sealed the tank and started the bodywork.  Hope to finish the bodywork on Saturday and get it in primer.

Took the family to the Black Hills in South Dakota.  I figured it was time they got to experience some of the awesomeness.  Just got home yesterday.  We drove the whole trip.  I prefer riding up there on the bike, but it was still cool.  Was there for five days. Saw everything from the Badlands to Devils Tower in WY.  We got there two weeks before the Sturgis Rally so there weren't a lot of bikes.  They started trickling in the last couple of days we were there.

I bought a whole bunch of t-shirts while we were there.  Some of the current herd needs to be downgraded to working-on-the-bike or yard-work shirts.

[Stev-o]

Welcome back Bud.  I've done the Badlands on bike, many moons ago.

[budman]

Welcome back Bud.  I've done the Badlands on bike, many moons ago.

Quite a site to behold, isn't it?

[SOHC4 Cafe Racer Fan]

I bought a whole bunch of t-shirts while we were there.  Some of the current herd needs to be downgraded to working-on-the-bike or yard-work shirts.

I do the same thing.  As they get faded and ratty, they become shop rags.

[Retro Rocket]

I bought a whole bunch of t-shirts while we were there.  Some of the current herd needs to be downgraded to working-on-the-bike or yard-work shirts.

I do the same thing.  As they get faded and ratty, they become shop rags.

Or fishing shirts....

[budman]

Or fishing shirts....

...and jeans.

[budman]

I finished the body work and primed the tank.  Just need to block sand it, reprime, wet sand and repaint.  Hopefully the bung relocation fiasco will be over soon.

I've also been working on a rear brake light switch bracket.  I made it out of stainless steel plate.  Looks like it'll work just fine.

[budman]

Now I'm finally back where I was about 7 weeks ago.  I got the gas tank repainted and the leaky fork seal replaced.  There's plenty of room for a petcock now.  Probably going to get a low profile Pingel petcock.

Hopefully I can get the graphics done on the tank next week and I can start making progress again.  I don't like being in "two steps back" mode again.

[beemerbum]

I hope you've got good bits and remember to chamfer the holes....

Evidently there are three schools of thought on chamfering after drilling (1) Don't chamfer as the pads will bite better and clean themselves. (2) Chamfer a little bit, to remove burrs if any. (3) Chamfer away as you please. On all my projects, I went with #1 with excellent results. Another thing to remember: The brake was designed with a no-hole rotor. Any change will reduce the brake's effectivness. All the modern bikes with heavily drilled discs were designed that way. Also, science tells us that none of the drilled holes should exceed the disk's thickness in diameter. That makes sense.

[Stev-o]

Good to hear, Bud.  You have 7 weeks to the Harvest Classic bike show to get it done!

[budman]

Good to hear, Bud.  You have 7 weeks to the Harvest Classic bike show to get it done!

As much as I would love to get the bike finished it doesn't look it's going to happen this year.  I have too many parts to still buy and not enough money to get what I need before the rally.

Are you going to have the park racer finished in time for the rally?