Topic: '78 750K first project by a car guy...

[madmtnmotors]

As far as I know, the titanium retainers require the use of the early style valve keepers, which require changing valves or having the later model valve stem machined for the early keepers. You might need to contact A.P.E. to verify. The only heavy duty retainers that I am aware of that are designed to work with the late model keepers are those at CycleX:

http://www.cyclexchange.net/Honda%20cb750%20(%2077-78%20)%20%20F%202%20Section%20Page.htm

but I could be wrong, I've been wrong before! The CycleX retainers are on my list for the next late model build.


The F2, K7 and K8 use the same retainers/keepers

[RandyBMC]

I've been working quite a bit lately on the bike.

No photos yet, but I took some (just didn't upload to Photobucket yet).  I like the Japanese 836 kit from what I've seen so far.  They came rather nice out of the box.  The machine shop finished up all of the recommendations for them.  They also did the head (I ended up with the CycleX heavy duty retainers and associated keepers and their super flow valves).  It all looks very pretty.

I did all the taping, stripping, and painting of the engine block, the cylinders and other miscellaneous bits and pieces.  I used the Duplicolor Semi-gloss Black engine paint.  Turned out clean, and with the polished covers should look pretty stunning.  Polishing is not fun for your neck and back and hands if you didn't know.  Getting old is not a good deal.

I stripped the tank I bought from Steve-o, and it is almost perfect underneath - no rust at all!  I understand the pull toward using clear coat on the tank when it looks that clean (but I still plan to paint it).

Now in at the reassembly point for the engine.  While the machine shop did a great job on the end gap for the rings, they took them out of the wrapper (which conveniently had a top ring label) and didn't label them.  I am guessing the silver edged ring is the top ring and the black is the other.  Anyone with these confirm which rings go where?  There is no stamping or marking on them that shows which way is up, but I think I can figure that one out by edge shape with a magnifier.  HELP please!

Thanks!

(Photos to follow when I have some time)

[RandyBMC]

The silver ring is the top ring, just looking at the chamfered edge on the top and bottom.  The second ring, however, looks identical on both top and bottom - I can't really see a "scraper" slant.

Waiting for ideas...

[Stev-o]

Sorry, can't help you with the rings.

But, to post pics, you can now attach as an attachment.  Look below the white box after you hit reply.

[FGKouki]

Almost always the rings will have a number or letter and that signifies the TOP side.  Otherwise you may have to get out some reading glasses and look at the profile where you have your gap. 

[RandyBMC]

Ugh, trying to upload straight from the iPhone doesn't seem to work - it says it can't accept .jpeg, only .jpg...

Back to finding time to upload to photobucket and use the img tags.

The rings - there is definitely not a pip or mark on the top of any of the rings.  I am 90% sure the silver edged top ring can go up or down, since the chamfer is on both edges.  I am less sure on the 2nd ring.  It seems, even with a magnifier, that the edges are straight (square).  I've always seen either a slant or a lip/step on the 2nd ring to "scrape" the cylinder wall (for break-in mostly, but I'm not sure that it doesn't help compression).

Has anyone seen a 2nd ring like that, and maybe the Japan eBay 836 kit has those (the kind with no slant or lip)?  My next step is to eBay communicate with cruisin' image (the eBay vendor).

Thanks again for everyone's input.

[RandyBMC]

The new workplace


The eBay CruzinImage 836 piston kit, which I'm pretty happy with


Painting the cylinders







Painting the block







Looking at it all coming together



The stripped tank looking industrial (still plan to paint)

[Desert-SOHC]

Coming along nicely

[SOHC4 Cafe Racer Fan]

Nice job on the engine paint.

[hondamad]

Looking good , i suppose you are itching to ride it

[Restoration Fan]

Nice work, Randy.

A couple of things:
1)  The rings we received for our 78 didn't have numbers on one set of those.  If you find that there are no numbers but one side is a bit shinier than the other, put the shinier side facing the top.
2)  There's an iPhone app for PhotoBucket that is free.  Download that and then hit the "Upload" button on the lower left of the screen.  You can then select the photos straight from your photo roll on your phone and upload them.  It works; I do it all the time.

Good luck man.  I still have a few 78 parts still laying around.  If you find you are in need of something, give me a shout and it's yours if I have it.

Ron

[RandyBMC]

Well, the piston install was fun.

Clocked the rings, installed the rings as I thought they should be - with the dual beveled silver lipped ring on top, the square edged number 2, and the oil rings.  No top or bottom orientation.

Installed onto the rods, slapped on some good old Permatex aviation 3 to the cylinder gasket and block, then used a combination of Popsicle sticks and generic ring compressors from Pit Posse (the Honda ones would've worked better as they are smaller).  A piston base stay would've helped too, but I made it work.

Now I am working toward getting the head on - installed the pins and rubbers, but the knock pins that locate the gasket on the cylinder and the head to the cylinder seem to be keeping the head gasket from laying flat.  I tried two different gaskets, same deal.  I swapped the pins and tried upside down and right side up on them as well, no joy.  I posted the photos at the end of the progress work.  Really hoping for some input!

















A shot of the drag bars I'm going to use.


The issue with the head gasket.  The knock pin is not completely down in the photos, but they have been every which way and I can't make either gasket lay flat.  The holes all line up almost dead on otherwise.

[FGKouki]

You can enlarge the holes on the headgasket with a dremel  and it'll fit great.  I've had to do this with both the engines I rebuilt and I think it's common with most aftermarket gaskets.

[RandyBMC]

Great, thanks for the tip.  I already went out to the garage this morning and did just that.  It fits like a glove now.

Advice on dry or not for the head gasket?  On the old stuff I worked on in the past, I used Permatex on all gaskets except for the head gasket (which would go on dry).

[RandyBMC]

Without further input from anyone that knows better, I have decided to put the head on with the gasket dry.  I put it on to check clearances, and all looks good - except that the head needs to go black now that I see it all together...



Then I used a shop light since I don't have an oven, and the valve stem seals are already installed, to do a semi-baking job.



I think it'll be worth the extra time in the end (taping off is a royal pain!).

I then found that I am missing a couple o-rings (the 11x2.5 pair that go with the head gasket and base gasket on each top and bottom of the cylinder).  I called and spoke with Mike at CycleX and he was super great and sent me a couple at no charge (I bought all of my cylinder head stuff from them)!  They are on the way.

My daughter then helped with some thoughts on the paint for the tank.  I would like to give a retro feel and nod to Honda with maybe a Super Sport style stripe on each side.  It's still in the works.  The grey is a non-metallic, dove grey like Toyota uses on the FJ or Audi/VW uses.  I think MINI has one too.  I'm leaning toward the grey tank with the black stripe and blue outline - opinions welcomed.





While waiting for the o-rings to show up, I will probably start on the frame and forks.  Is it the inner shoulder that folks recommend massaging with a grinder to assist in installing/pulling the engine?  On the right side forward lower mount?

Thanks again for the help and any opinions.

[Retro Rocket]

  I don't know how to use photoshop either....

I like the F2 style paint ideas...

[RandyBMC]

Found the issue on this page that was making the font small - whew!  It was too hard to read.

For those that missed the questions because of the tiny font, there were two:

1.  Does anyone use anything on the head gasket, or do you put it on dry (my inclination, and what I read in the manual state dry, but I don't want to negate those with years of knowledge on this bike)?

2.  Now that I am starting on the frame, should I grind the lower front, right engine mount flange down level to the top of the mount for easier installation and do you have photos?

Thanks!

[madmtnmotors]

1. I have had good results mounting the head gasket dry

2. Yes. Just grind the bumps on top down flush.

[Stev-o]

1. I have had good results mounting the head gasket dry

1. +1 Dry, however, I had a small leak on my Kaw, I replaced the gasket and reinstalled with a light coat of Permatex Copper spray a gasket, no issue since.

What gasket set are you using?

Have you heard of Hondamans book?

[RandyBMC]

The one that came with the CruzinImage pistons.

I have heard great things about Mark's book, but every time I get $85+ there is stuff I need for the motorcycle (like his ignition set up!).  I'm sure it is more than worth the cash, I just have to sparingly use money for the bike project or sleep on the couch.

[Restoration Fan]

1. I have had good results mounting the head gasket dry

Same here.  We didn't put any gasket sealant on the head gasket.  Used the Vesrah head gasket that came in the Vesrah kit.  Tightened it down, let it sit overnight and then re-torqued it again.  Successful so far.

[Restoration Fan]

Randy,
You have downloaded the version of the Honda manual that is specific to the K8/F3 models, haven't you?

If not, you can download it from my Google Drive location.
https://drive.google.com/open?id=0B4nqeBb662mZTExFNDdwY0JyRlU

[RandyBMC]

I do have that one.  I have been using the other shop manual (blue and white cover with the wheel) because I printed that one out before I found the '78 manual.  I refer to it though using the iPad.

Thanks for the link!

[Restoration Fan]

A word of caution; a fair amount of things changed in the 77 and 78's.  You'll find quite a few variances (carbs, breather beneath the battery box and the hose routing there, rear wheel size, rear wheel hub, choke cable vs on-carb choke) on your bike from that manual.  Just make sure you check the 78 manual if something doesn't look right.

[RandyBMC]

Thanks Restoration Fan.  I have been doing just that with the iPad manual from your Google Drive - it has been very helpful.  Since my bike came in baskets, I've had to figure out just what it's supposed to look like.  At least the engine was still on the chassis.

Speaking of figuring out what it's supposed to look like, I took off the center stand and removed the forks today.  Found an interesting spring set up between the center stand and the rear brake actuator.  I took a few photos of it if I ever want to reinstall the center stand (I plan to just find a side stand for it).  Thought it may be helpful to anyone else needing a reference:



I also worked pretty hard tonight to revive the forks.  Before and after (actually side by side, but you get the picture).  Someone already had a half hearted go at cleaning them up with what looks like a grinder!  I was able to clean the marks up by polishing it out.



Now I need to rebuild them with a progressive kit.  I am thinking of doing a shorter spring in the front - input?