Author Topic: Bessie, my first rebuild: 78 CB750F3 (Back on the road 2016-05-12) (Read 70413 times)

wohali · « **Reply #125 on:** May 01, 2011, 06:48:56 PM »

Thanks for the kind words on the pictures!

I misspoke - I meant to say "Buy new 12.9 hex-head screws." I used these on the all the covers (cylinder head, alternator, crankcase/gear shifter, clutch, points) as well as 3 new M5s to hold the points in place. I only used anti-seize with these screws, since I didn't want to have to worry about bad torque values elsewhere, and in fact the anti-seize could cause bigger problems in certain areas (head nuts).

wohali · « **Reply #126 on:** May 01, 2011, 07:08:50 PM »

More pics!

Today, I got the front wheel cleaned up and replace its bearings (gallery here). It went from this:

To this:

I completed rebuilding the shocks as well:

My welder (thanks doozer!) also completed work on the excellent Gordon frame kit. Full gallery with step-by-step photos here.

He writes about the experience:

Quote from: doozer

It wasn't really all that difficult, other than the cleaning. I used an arc welder, set at 55A DC+ and 7018 3/32" welding rod. Keep the rod warm and, for best results, warm the frame too. If you don't care if the welds are visible, this is pretty fast. If you want a finished look like in the gallery, you need to do multiple passes to be sure you get proper penetration, and leave enough weld material behind once you've cleaned. Gross cleaning was done with a hand grinder; final cleaning was done with a double-cut bastard file and sandpaper. The tack holes on the side really help to keep things in place without messing up the main weld area. Overall effort was about 12 hours, including prep, cutting, welding and cleaning.

One note: the rear cut needed to be adjusted from the plans. The dimensions given didn't allow enough space for the frame kit itself to fit in. We kept the rear-most cut at the dimensions given, and cut the removable section another 3/8" forward to allow enough space. Measure carefully!

A very productive weekend in the shop. She's almost done...just in time for "it"!

Next up: frame painting (POR-15 + Chassiscoat satin black), engine reinstallation, first fire test.

brandEn · « **Reply #127 on:** May 01, 2011, 07:28:58 PM »

looking good. Those wheels cleaned up nice. I am looking forward to seeing this one completed.

HedNut · « **Reply #128 on:** May 04, 2011, 06:15:41 AM »

Great build and well documented Wohali!! The kit looks great in your frame!!

Cheers,
Hed

wohali · « **Reply #129 on:** May 08, 2011, 06:40:16 PM »

After a ridiculous amount of showering, I finally got all the greenblast (recycled post-consumer glass bead) out of my hair. The frame and bits have been sandblasted, coated with POR-15, and then with Chassicoat (semi-gloss black). I've also had to take the blaster to the pipes, which have been primed for the moment. (Still planning my next move, there.)

Everything is set to fire up the engine for a test tomorrow or Tuesday.

The delays are frustrating but I am so happy to be this close to done.

Also, parts back from Mayfair Plating in Toronto - great guys, still do hex chrome, looks astoundingly good. Their comment was that "the parts were paper thin" - perhaps cost savings in the F2/F3 models?

wohali · « **Reply #130 on:** May 10, 2011, 09:11:33 AM »

After a long night in the workshop, everything necessary to make the engine spin is in the frame. With any luck she'll be starting up tonight!

wohali · « **Reply #131 on:** May 10, 2011, 09:34:06 PM »

She ran!

I am very happy. There's still some problems to work through, but the engine sounded great and fired up well, once I realized the carbs weren't going to fight well against the vacuum in the air-capped gas feed I was using.

Bugs to work out:

Carbs are leaking like sieves. Guess I can't get out of a quick rebuild, even though I did it 5 years ago already. Fortunately I have a full set of gaskets and rings.
#3 still isn't firing, based on results with a laser/IR temp probe on the exaust manifold. #2 is, and swapping the wires for #2 and #3 makes #3 fire. It got late so I didn't let it run long enough to see if it'd eventually go. Pulling the plug, it looked black, wet and oily, but that's not a good indication...since there would have been oil in all 4 cylinders at reassembly time.

Tomorrow: pull the F3 (PD42A) carbs and do a quick rebuild, reset jets to factory settings, and try again.

~~I have some video I'll be posting shortly, as soon as the cat gets off my lap~~ Video has really bad audio, makes it sound like it's sputtering. As good as my still shots are (I believe, anyway), I think I need a new video camera.

wohali · « **Reply #132 on:** May 10, 2011, 10:19:44 PM »

Pics:

I did the frame with 1 coat POR-15 and 1 coat Chassiscoat. Looks fantastic:

I had no idea that the small plastic tube on the kickstand is actually transparent, if a bit yellowed by the years. I thought it was opaque grey/black like fuel/breather line!

Ready for testing with just the bare essentials. 30s after this picture was taken, she turned right over.

Turns out my oil pressure sensor has crapped out. I guess this gives me an excuse to get a real pressure gauge! Looking at this one on eBay from tasclassicmotorsports; this seems to be a decent set.

wohali · « **Reply #133 on:** May 10, 2011, 10:59:19 PM »

FYI I Found the source for the "mini-mini" 1" oil gauge CycleX is selling. It's a Sifton, and I think it's made by V-Twin Manufacturing. Part number is 40-0589 and it's available at http://xrl.us/sifton1inch for about $40US.

Damfino · « **Reply #134 on:** May 11, 2011, 07:47:36 AM »

Be wary of TAS Classic Motorsports... $:-\$

http://forums.sohc4.net/index.php?topic=71073.0

brandEn · « **Reply #135 on:** May 11, 2011, 07:53:20 AM »

Quote from: wohali on May 10, 2011, 10:59:19 PM

FYI I Found the source for the "mini-mini" 1" oil gauge CycleX is selling. It's a Sifton, and I think it's made by V-Twin Manufacturing. Part number is 40-0589 and it's available at http://xrl.us/sifton1inch for about $40US.

I just got one of these and its nice, $25 US, cant be beat but Carpy sells them for $55 so they must be good! (sarcasm of course)
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=220651562550&viewitem=&sspagename=STRK%3AMEWNX%3AIT

wohali · « **Reply #136 on:** May 11, 2011, 08:47:22 AM »

That Sifton gauge is really the one I want (1" instead of 1.5" diameter), but I still need the oil gallery fitting and elbow. Does anyone else fab/sell these? I don't want to tap the OEM one out myself if I don't have to.

SOHC Digger · « **Reply #137 on:** May 11, 2011, 01:54:07 PM »

CycleX sells these that I think are gorgeous. $80.95 available in black or raw for the gauge and adapter.
http://www.cyclexchange.net/Machine%20Dress%20Up.htm

mrrch · « **Reply #138 on:** May 11, 2011, 07:31:40 PM »

That looks like the elbow Joker Machine makes.

SOHC Digger · « **Reply #139 on:** May 11, 2011, 07:45:18 PM »

Quote from: mrrch on May 11, 2011, 07:31:40 PM

That looks like the elbow Joker Machine makes.

Yep, and $9 cheaper.

wohali · « **Reply #140 on:** May 13, 2011, 08:38:08 AM »

The carbs are back on the bike. The Form-A-Gasket 1 worked perfectly. I can even use the drain screw still!

Thanks for the advice, but that's 2x what I had been planning to spend on a gauge...pre shipping. Think I'll take my chances with TAS and see what happens. Looks like the only real issue is staying on top of shipping. OK, you convinced me. That Joker elbow is very nice, especially how you can adjust the viewing angle without having to muck with the elbow position. I went ahead and ordered from the Canada reseller of CycleX stuff.

Should be starting it up again tomorrow, get the wheels back on...that will leave just the manifold to be refinished, the brakes to redo, and I need to repaint the tank and new side panels. Won't stop me from riding it before then tho

wohali · « **Reply #141 on:** May 15, 2011, 10:47:24 PM »

Lots of work this weekend. Yesterday I rebuilt the rear wheel, including bearing replacement; came out looking as good as the front wheel. I also POR-15'd / Chassiscoated parts I'd forgotten to do: swingarm + torsion bar for the rear caliper, triple clamp and steering stem, the lower part of the front forks, the chain case (it was wrecked - un-rechrome-able, still watching for a like-new one, so black it is for now) and the battery box.

Today I got both wheels back on the bike! What an amazing feeling. The forks look fantastic, and those new steering bearings make the front feel like a brand new machine. I still can't get over how easily it steers, and how easily the front and rear wheel spin on their axles now. It used to take considerable force to get them to turn, even with the brakes removed. I'm thrilled at the progress. I also got a few other bits taken care of, like the kickstand and the pillion step.

My welder came over to help a bit more with the exhaust manifold. The reduced diameter portion that connects to the muffler was a nightmare. The PO had layered ring after ring, then welded the entire thing together, to make it approximate the diameter of the POS muffler he'd bought. (That POS was painted red, then black, then used a hose clamp to attach to the frame.

Awful!) After removing all the added layers of metal, this is all that was left of the original manifold connector:

After a trip to Canadian Tire for a suitable adapter to cannibalize, and some welding with 1/16" 6013 rod, this was the result:

He also had to use some 3/32" 7014 to fill some holes in the bottom of the manifold where I didn't feel comfortable welding it myself. The metal had become paper-thin in spots...as a result, I'm not taking the manifold in for chrome ceramic coating, I'm just going to rattle-can it for now, and keep my eyes out for a decent used/NOS replacement someday. I'll put up more pictures of the manifold surgery once the whole thing's been painted, in case anyone's thinking about doing this themselves in the future.

New picture galleries:
Crankshaft cleanup and measurement - I had forgotten to post this.
Frame painting and reassembly - updated with wheel attachment pictures and closeups of the rear brake mounting. Includes a picture of the weird green PJ1 fork oil!

wohali · « **Reply #142 on:** May 16, 2011, 08:54:31 PM »

Tonight was a short night - cleanup on the wiring harness. It's ready to go back on the bike. Also, some more welding and grinding. I'd hoped to paint it today but it has to cool before I can finish up...needed a lot of hole plugging before it was going to be serviceable.

Zaipai · « **Reply #143 on:** May 17, 2011, 07:06:41 PM »

Very nice so far. I gave up on finding a NOS exhaust however for the 750's they are out there. Probably pricey tho.. However not sure.

.: Scott :.

kap384@telus.net · « **Reply #144 on:** May 18, 2011, 07:53:13 AM »

There's been a complete NOS one for sale on fleabay for the past month. Asking $1750 though

wohali · « **Reply #145 on:** May 18, 2011, 05:05:37 PM »

Yeah, ridiculous on the exhaust for $1750... maybe someone will buy it, but not me

Found a replacement horn for $20 today. The horn I have is clearly off an older K series (the single horn with the sideways output and the single screw for adjustment, as opposed to the double-horn unit). Looking forward to it arriving and retiring this other one. It sounds not so much like a horn and a lot more like a bicycle hand-squeeze horn

Anyway, manifold is coming along, should have photos later tonight. Some lint fell on the pipe for #3 and got embedded in the fireproof coat, so I'm going to try a fast wet-sand of it and repaint it before I do the finishing coat.

Last night, also got the harness fully on. Switched to some of the standard wiring jacket stuff, the stuff that looks like corrugated plastic tubing. It's a bit thick for the original routing and ties, so I got some larger ones from Honda, as well as changed the routing slightly to be more like the older "K" bikes. I know, I know, gasp - wohali's doing something NOT 100% resto! yeah, well, I did a few other things too...

Like installed Hondaman's ignition last night. Hope to test it tomorrow. Real snazzy. In case anyone wonders, yes, run the green ground wire to the points, not up to the coils, and you can push it thru the rubber bung in the hole by the points if you remove it from the hole first. That'll let it stretch enough to let the crimped O connector go thru. Because it's a '78 F3, the only place I could put the box and still have access was in the tool tray. So I ended up cutting a small notch in the tray to let the wires through. I still have enough room in the tray for the shock wrench and a few spare bits (like a house key or some screws). The rest will go in the fender storage (which I LOVE btw!)

Also got all the routing for the air box done, carbs, drains and the like. She's really almost done...of course there's still the little matter of the brakes

More pics shortly.

bluesmoke69 · « **Reply #146 on:** May 18, 2011, 10:06:52 PM »

Looking good!!

fastbroshi · « **Reply #147 on:** May 19, 2011, 04:32:55 AM »

Subscribed

wohali · « **Reply #148 on:** May 19, 2011, 11:32:19 PM »

Tonight: Manifold installed (looking OK - hope she'll hold up, both cosmetically and integrally, for a few more years).

Also rebuilt the rear brake caliper; the master cylinder seems to be OK. The piston was stuck solid; only the grease gun approach worked. Not sure why I couldn't pump it out with the MC...and air didn't work worth a damn. Had to unstick it with a vice first, then used the grease to pop it out. Fully rebuilt, reassembled, put on the new stainless steel brake line, and bled it by pumping back thru the bleeder valve with a little hand pressure/vacuum pump tool I got at Canadian Tire for $30. Really painless operation. Tested the rear brake by hand; it seems to be doing a decent enough job of stopping the rear wheel, as well as I can do by hand anyway.

Also dressed the remaining wires on the harness (from Hondaman's ignition box).

Tomorrow: buying a zerk for the rear brake pedal pivot point, drill/tapping it in, installing the pillion/brake/muffler, and hopefully rebuilding the front brake calipers.

Saturday: Handlebars + cluster + controls, seat, tank. With any luck: VROOM.

wohali · « **Reply #149 on:** May 21, 2011, 10:09:13 AM »

TRAGEDY!

Front master cylinder decided to start leaking. So she can't be ridden safely, and I couldn't even get her to bleed correctly. The brakes have been fully cleaned and reassembled, but with the long weekend this weekend in Canada, I'm thinking I'll order an OEM kit from Z1 today and it'll get here Tues or Weds.

Another sunny weekend wasted

And "it" is getting closer...man I am feeling the pressure

In other news, muffler/pillion/brake pedal are all installed, rear pedal works all right, and the new AGM battery is on the tender. Today I'll probably finish everything else I can: handlebars, cluster, rear fender, seat, fuel tank and all the shiny shiny re-hexavalent chromed bits.

News:

Author Topic: Bessie, my first rebuild: 78 CB750F3 (Back on the road 2016-05-12) (Read 70413 times)