Author Topic: CB750 K4 Build - The Cafe Tracer (Read 118866 times)

budman · « **Reply #200 on:** February 09, 2016, 10:32:14 AM »

I just bought an engine. '74 too, so it'll match the frame. 28,000 miles. Can't wait to dig in.

Stev-o · « **Reply #201 on:** February 09, 2016, 02:14:30 PM »

Quote from: budman on February 09, 2016, 10:32:14 AM

I just bought an engine. '74 too, so it'll match the frame. 28,000 miles. Can't wait to dig in.

Good news! When will you have it? And what are the plans for it??

budman · « **Reply #202 on:** February 09, 2016, 02:40:31 PM »

I should have it in about a week. I'll probably rebuild the top end no matter what. At the very minimum I'll pull the head and the cylinders, probably have the head rebuilt...see what kind of condition the pistons and cylinders are in. Paint and polish everything that needs it. Probably get a new bolt kit, new starter, new clutch, electronic ignition, etc.

I have the carbs from the old engine. They are in very good shape. Just need a rebuild.

I'm not really looking to hot rod anything at this point. A solid runner is all I really want right now.

SOHC4 Cafe Racer Fan · « **Reply #203 on:** February 09, 2016, 03:28:09 PM »

If the new stock motor has no evidence of leaks and has good compression, why pull apart the top end at all?

budman · « **Reply #204 on:** February 09, 2016, 04:08:52 PM »

Quote from: CB750 Cafe Racer Fan on February 09, 2016, 03:28:09 PM

If the new stock motor has no evidence of leaks and has good compression, why pull apart the top end at all?

Paint and polish.

mystic_1 · « **Reply #205 on:** February 09, 2016, 04:20:23 PM »

Here's the thing about this rabbit hole, though: once the top is off, you're only a few bolts away from being able to put in a new cam chain.

mystic_1

budman · « **Reply #206 on:** February 11, 2016, 07:23:35 AM »

Quote from: mystic_1 on February 09, 2016, 04:20:23 PM

Here's the thing about this rabbit hole, though: once the top is off, you're only a few bolts away from being able to put in a new cam chain.

mystic_1

There's that, but there's ways around it.

budman · « **Reply #207 on:** February 11, 2016, 07:34:03 AM »

Yesterday I got in some new bolts for the rear shocks for mounting the shocks to the swing arm. The ones that came with the shocks look cheap. While I was messing with that I noticed the rear sprocket chain plate hits the base of the shock. The new shocks have a much wider base than the stock shocks. I can either remove the sprocket plate completely or I can machine the lip off it. I actually kind of like the look of the plate. I realize the plate is there to keep the chain from possibly wedging between the swing arm and the hub if it ever flies off, but is it essential?

mystic_1 · « **Reply #208 on:** February 11, 2016, 03:10:54 PM »

Quote from: budman on February 11, 2016, 07:23:35 AM

Quote from: mystic_1 on February 09, 2016, 04:20:23 PM
Here's the thing about this rabbit hole, though: once the top is off, you're only a few bolts away from being able to put in a new cam chain.

mystic_1

There's that, but there's ways around it.

Very true, but it's just a few bolts, and then you'd also have the opportunity to plastiguage your crank and rod bearings.

Oh and also replace those pesky seals at the right side crank and final drive shaft. They're 40ish years old!

Plus you'd be able to clean out the grunge that accumulates below the transmission, that stuff never flushes all the way out of the sump.

AAaaand, inspect/replace your shift forks for smooth shifting.

Really, if you're going to take the motor most of the way apart anyway, why not go all the way?

mystic_1

budman · « **Reply #209 on:** February 11, 2016, 04:42:30 PM »

Quote from: mystic_1 on February 11, 2016, 03:10:54 PM

Quote from: budman on February 11, 2016, 07:23:35 AM
Quote from: mystic_1 on February 09, 2016, 04:20:23 PM
Here's the thing about this rabbit hole, though: once the top is off, you're only a few bolts away from being able to put in a new cam chain.

mystic_1

There's that, but there's ways around it.

Very true, but it's just a few bolts, and then you'd also have the opportunity to plastiguage your crank and rod bearings.

Oh and also replace those pesky seals at the right side crank and final drive shaft. They're 40ish years old!

Plus you'd be able to clean out the grunge that accumulates below the transmission, that stuff never flushes all the way out of the sump.

AAaaand, inspect/replace your shift forks for smooth shifting.

Really, if you're going to take the motor most of the way apart anyway, why not go all the way?

mystic_1

I'll just have to see what I end up with. This is my first CB750 build. I'll have to turn some wrenches, check it out all out and hopefully make some good decisions.

budman · « **Reply #210 on:** February 11, 2016, 04:46:02 PM »

My risers arrived so I had to checkout the handlebars. Seem a tad bit wide. I'll have to see how the controls fit. Might end up lopping an inch off of each end.

budman · « **Reply #211 on:** February 12, 2016, 09:13:48 AM »

Look what arrived today.

SOHC4 Cafe Racer Fan · « **Reply #212 on:** February 12, 2016, 03:38:34 PM »

Quote from: budman on February 12, 2016, 09:13:48 AM

Look what arrived today.

Free or seized?

budman · « **Reply #213 on:** February 12, 2016, 03:56:43 PM »

Quote from: CB750 Cafe Racer Fan on February 12, 2016, 03:38:34 PM

Quote from: budman on February 12, 2016, 09:13:48 AM
Look what arrived today.

Free or seized?

Supposed to be free and shift smoothly. It's still in the back of the truck wrapped in plastic. I won't be able to get to it until tomorrow.

budman · « **Reply #214 on:** February 13, 2016, 07:18:55 AM »

Doesn't look to bad really. Kicks over. Feels pretty good. Somebody added an oil pressure gauge. Only has one bent fin on the cylinder head that I can see.

mrbreeze · « **Reply #215 on:** February 14, 2016, 02:17:39 AM »

I just read this build all the way through....43 pages. Digging the project and your skills (oh...and the pan head too!!). Just like you thinking about the wooden seat....I was thinking about the oil line. It's gotta be a 3/8 NPT in my eyes because the next size down is 1/4 and that's too small diameter. So the 3/8 thread will bite ok with JB for sealer? My plan was to put a female 3/8 on that side and a male 8an on the other. It may be overkill being that there's no pressure on the hose but this way I won't ever have to buy the whole line again.....just the hose only. That's how I did my oil cooler hoses.

budman · « **Reply #216 on:** February 14, 2016, 07:11:38 AM »

Quote from: mrbreeze on February 14, 2016, 02:17:39 AM

I just read this build all the way through....43 pages. Digging the project and your skills (oh...and the pan head too!!). Just like you thinking about the wooden seat....I was thinking about the oil line. It's gotta be a 3/8 NPT in my eyes because the next size down is 1/4 and that's too small diameter. So the 3/8 thread will bite ok with JB for sealer? My plan was to put a female 3/8 on that side and a male 8an on the other. It may be overkill being that there's no pressure on the hose but this way I won't ever have to buy the whole line again.....just the hose only. That's how I did my oil cooler hoses.

Yep, the JB weld will work just fine to seal the NPT threads. Just make sure the parts are clean first. The adapter is the way to go, but you might think about using an elbow instead of the straight adapter. It looks like with the way your setup is the oil lines might stick out the side of the bike too far.
Something like this: http://www.mcmaster.com/#50715k184/=114e2m8

budman · « **Reply #217 on:** February 14, 2016, 03:44:22 PM »

Started the seat pan today. Made pretty good progress. Polished the side cover too. Wanted to see what it would look like.

mrbreeze · « **Reply #218 on:** February 14, 2016, 09:40:09 PM »

Cover looks good man! I see ya got the Joker brake stay. Me too although it's hard to see with the megaphone mounted.

budman · « **Reply #219 on:** February 15, 2016, 06:18:27 AM »

Thanks. It still needs a bit more polishing. Couldn't spend any more time on it right now. Got a million things to do.

I'm going to use the JM brake rod too. Some of their stuff is a little too fancy for me, but I like these parts.

budman · « **Reply #220 on:** February 15, 2016, 05:30:19 PM »

The headlight came in today.

Stev-o · « **Reply #221 on:** February 16, 2016, 09:37:33 AM »

Makin good progress, Bud.

budman · « **Reply #222 on:** February 20, 2016, 04:14:00 PM »

The seat pan is pretty much done. Just needs paint, padding and leather.

I'm going to try to get the front wheel installed tomorrow.

budman · « **Reply #223 on:** February 21, 2016, 06:27:49 PM »

She's a roller!

Stev-o · « **Reply #224 on:** February 21, 2016, 07:23:51 PM »

WooHoo!

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Author Topic: CB750 K4 Build - The Cafe Tracer (Read 118866 times)