Topic: CB 750 K0 — Me and the dog are building a bike. Finished!!

[edwardmorris]

Sorry about the rushed reply, stick with OE or at least find good viton ones if you don't want oil leaks and a top-end redo. My Vesrah kit was missing bits all over the place but I never planned on using the o-rings or puck in there anyway. OE is the way to go if you don't wanna chance it IMO.

[seanbarney41]

that's a big +1...these are not chevy small blocks...get as much Honda oem as you can, cuz 4-1 sells chinese junk

[Davez134]

Make sure to measure the thickness of any generic o-rings against factory spec with a set of calipers. They need to have a certain percentage of "squish" and that is very important

[dolamike]

Make sure to measure the thickness of any generic o-rings against factory spec with a set of calipers. They need to have a certain percentage of "squish" and that is very important

Thanks, I decided to pony up for the OEM ones. I'd hate these to fail. I do wonder if there is a difference though... as far as the rubber goes.

[dolamike]

Build update.

Pistons are back on the engine, rings installed. Hardest part was the wrist pin clips, a true test of patience.



I'm also happy to report that the battle of the swing arm bushings is over, I can finally claim victory. In the end a heat gun and blind hole bearing puller did the job. With about 200 strikes. I hope what they say about the brass bushings is true!



In other news...

I just got these in the mail!



It's time to get the frame ready.

[754]

Mike, i have a concern about the pipe mounts.
Cutting them off they may be a bit shorter, which may be an issue with stock pipes.
 Might need an internal sleeve tacked in to move it back an 1/8 inch, then the gap can be filled with weld.
Just think it through rather than having your pipes not fit properly..

[dolamike]

Mike, i have a concern about the pipe mounts.
Cutting them off they may be a bit shorter, which may be an issue with stock pipes.
 Might need an internal sleeve tacked in to move it back an 1/8 inch, then the gap can be filled with weld.
Just think it through rather than having your pipes not fit properly..

Thanks Frank, I have the exact same concern. They will definitely need a little more length.I like the internal sleeve idea. I'm going to use the drawing below for my measurements. The one I am uncertain of is the distance between the two exhaust mounts. You wouldn't happen to have a frame you could measure would you?

Is it the 174.6 from the top view, or the 238, or different? Any info would be much appreciated.

[Davez134]

Is it the 174.6 from the top view, or the 238, or different? Any info would be much appreciated.

It's different. I believe those measurements are of the top of the frame by shock mounts. Just went out to look at my K2, and just a quick eyeball with a tape measure shows to be just shy of 11 inches between the insides of the mounting holes. Sorry I can't get any more exact, as my bike is complete right now and all that crap is in the way!

[Greggo]

Hey, here it is!  Looking good so far!

[dolamike]

I just got confirmation that the measurement is 10-5/16" inside to inside.

Thanks Swoop!

[dolamike]

Merry Christmas!!!

Santa showed up a little early this year! I've been driving bye a bike sitting in the rain in a driveway 4 blocks from my house for awhile now. Tonight I decided to stop and see if they would be willing to sell it. $350 bucks later and I've got myself a K1. Woot! She's rusty but she's still pretty to me.

I think it will have many of the small bits I'll need to complete the K0, or maybe I'll save it for next winter... we'll see.

[kmb69]

I have a Sandcast frame 1004278 out and stripped right now and it measures 265mm or right at 10-7/16".
Pretty sure your K0 should be the same.
Nice score on the K1. 

[danyo]

I went to measure my K0 and is exactly between two previous measurements 10-3/8. I don't think one sixteenth one way or another will make difference.

Sent from my SM-N900T using Tapatalk

[Restoration Fan]

Nice score with the K1 and very good work on the K0 so far.  Enjoying this build thread a lot.

[mrbreeze]

Merry Christmas indeed!! Cool score on the K1 and the price was better than right just by looking at the picture. Did you get a title? Is the engine free (not locked up)? What kind of shape are the pipes in? Having this is a great addition to having a KO also. You can have a runner while you have a project! Have fun with it man.....I envy you!!

[mrbreeze]

Just a quick look see at the pics you have posted.....I see a correct tail light, gauges and unicorn (check for presence of D washers and look closely for cracks), headlight bucket. Can't tell about different forks between the 2 bikes....no gaitors present. You have the footpeg/ exhaust mt. triangles in place. Can't really see if it's correct but stock airbox. Just that unicorn alone was a worth a good chunk of the $350 you paid for the whole thing. Damn!!!......I might be as excited as you are!!

[kmb69]

I went to measure my K0 and is exactly between two previous measurements 10-3/8. I don't think one sixteenth one way or another will make difference.

I think your are correct - probably doesn't make much difference. Interesting to see the variation.

[mrbreeze]

I would beg to differ.....measurement is critical when you go to hook the pipes together in the rear. For best results I would suggest just tack welding and fitting the pipes first before making the final welds.

[kmb69]

I would beg to differ.....measurement is critical when you go to hook the pipes together in the rear. For best results I would suggest just tack welding and fitting the pipes first before making the final welds.

Tacking and fitting is an excellent idea. I doubt +/- 1/16" makes much difference in the "width" over the 38" length from the cylinder head to the rear mounts. I think the "length 225mm" and "height 78mm" location is more critical. Very likely that the variation of the pipe dimensions themselves are in the +/- 1/16" range. I have frequently had to "bend / tweak" brand new muffler sets to get them to match up at the rear.

[Swoop]

I have a Sandcast frame 1004278 out and stripped right now and it measures 265mm or right at 10-7/16".
Pretty sure your K0 should be the same.
Nice score on the K1. 

Thanks for correcting me Keith.

[mrbreeze]

I would beg to differ.....measurement is critical when you go to hook the pipes together in the rear. For best results I would suggest just tack welding and fitting the pipes first before making the final welds.

Tacking and fitting is an excellent idea. I doubt +/- 1/16" makes much difference in the "width" over the 38" length from the cylinder head to the rear mounts. I think the "length 225mm" and "height 78mm" location is more critical. Very likely that the variation of the pipe dimensions themselves are in the +/- 1/16" range. I have frequently had to "bend / tweak" brand new muffler sets to get them to match up at the rear.

Yeah...that's exactly where the problem is. If you just tack the triangle in place first, you can see if any adjustment will be needed. If you have problems with a frame where the triangle is already in place, it can be a bear to tweak the mufflers to fit.

[kmb69]

Thanks for correcting me Keith.

Steve, I was not correcting, just reporting my finding on one unmolested frame. Knowing how Honda "usually" designs stuff, the 265mm sounded like a good "nominal" number to me. Pretty sure they vary some even though they were jig welded at the factory.

Yeah...that's exactly where the problem is. If you just tack the triangle in place first, you can see if any adjustment will be needed. If you have problems with a frame where the triangle is already in place, it can be a bear to tweak the mufflers to fit.

Yes, it sure can be a bear. I have experienced fitment issues on stock frames with stock replacement pipes. Bending/tweaking them is tough enough not to mention deciding where they need to be adjusted.

[754]

I have a pair of nos muffler bolts that go in the hole in that frame triangle. They are different part number than later ones or maybe even KO.
 So something changed..might just be the bushing welded to the pipe, that the bolt passes thru..

The other tricky part here is moving them back a bit to rear, that is why I suggested sleeves.

[mrbreeze]

I sold a pair last year but they were K5. Didn't know there was a difference. One more for my learned something new today files!

[kmb69]

I have a pair of nos muffler bolts that go in the hole in that frame triangle. They are different part number than later ones or maybe even KO.
 So something changed..might just be the bushing welded to the pipe, that the bolt passes thru..

The other tricky part here is moving them back a bit to rear, that is why I suggested sleeves.

The very early ones were shorter. The bushings in the mufflers changed. Not sure what VIN was the cutoff.