Author Topic: Paddy - '78 CB750 - Version 3.0 Coming Soon!  (Read 84210 times)

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Offline liPPy

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Paddy - '78 CB750
« Reply #175 on: March 06, 2012, 09:35:14 pm »
Stev-O, I'll post a video once Paddy is up and running so you can hear him ROAR!

liPPy, you're right, I did have some alignment issues with the air box.  I remember searching last April and learned many of us battle the same issue with the K7/K8 model.  Try this, if you haven't already:



It took me using a ratchet strap to finally fully seat the carbs on the intake rubbers.  If the clamps on the carb-side of the intake rubbers aren't resting on (or dang close to) the carbs' stay plate, they're not fully seated yet.  Without doing this, I could never get the carbs forward far enough to align the air box bolt holes with the frame mounts.

Let me know if that helps ya, and good luck!

That looks like it might be worth a try.

Did you use new carb boots or use the old ones? I have a thread describing my current headache with using new rubbers and I wonder if you had the same issue and if the above fixed it!

Tomorrow I'll be pulling out the ratchet strap...



Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Paddy - '78 CB750
« Reply #176 on: March 06, 2012, 11:14:21 pm »
A heat gun used on the intakes might not hurt just don't melt or burn them. I gotta say I have not tried this myself but I do use heat in other situations involving rubber/rubber-like pieces. 
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline MoMo

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Re: Paddy - '78 CB750
« Reply #177 on: March 07, 2012, 02:59:33 am »
A heat gun used on the intakes might not hurt just don't melt or burn them. I gotta say I have not tried this myself but I do use heat in other situations involving rubber/rubber-like pieces. 


Jerry,  a heat gun is mandatory and works well.  I've never had a problem seating carbs after either the xylene/wintergreen treatment or use of a heat gun...Larry
« Last Edit: March 08, 2012, 12:26:32 am by MoMo »

Offline theofam

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Re: Paddy - '78 CB750
« Reply #178 on: March 07, 2012, 07:53:00 pm »
liPPy, I used new intake boots from carb to cylinder.  If you read back a ways, you'll see why that was necessary (HINT:  a visit from my local FD).

Jerry/MoMo, good tip on the heat gun.  I don't have one, but why not add another tool to the garage?!  ;D

I spent today troubleshooting the right rear blinker, neutral light and intermittent lo-beam.  I powder coated the rear turn signal stalks.  It turned out the right rear turn signal body wasn't grounding to the stalk.  So, I ground the powder coating off the stalk, mounted the turn signal body to the stalk and it worked!

My blinkers are pretty slow and I noticed some electrical tape near one of the main negative connectors on the harness.  I took it off, and it was covering a nearly cut wire:



I soldered it up and the blinkers are still slow (while the engine isn't running), but I was glad to have soldered a better connection.  I think they'll speed up at RPMs once the motor runs.  If not, I may try a Popwood Ground.

My headlight hi/lo switch almost seems like the pin holding it together is too tight, because the phenolic board seems to flare out at the back:



I used a vice grip to turn a 90 degree angle on the end of the bracket that covers the headlight switch:



That put enough pressure on the phenolic board to make more solid contact and operate the lo-beam consistently.  Another one checked off!

As for the neutral light, it helps to have the bike in neutral . . . VIOLA!  The neutral light works.  What worries me is that I thought the bike was in neutral (back wheel was spinning) when it was really between 4th and 5th.  I tried a few times, and I'm getting false neutrals on some downshifts.  Is it possible I put the tranny back together incorrectly?  Man, I sure hope not!!  :o

I moved on to fixing the leaking oil lines with my recently purchased crush washers.  I thought I could drop the rear wheel to get access to the rear oil line, but I still couldn't reach it.  So, off came the rear fender to allow me to remove the mudguard.  One step forward, two steps back!!



I put three quarts in to test whether it'll leak again.  So far, so good.  After five hours, it hasn't leaked.  If it's still good in the morning, I'll reassemble the back end.

That's it for today.


Offline theofam

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Re: Paddy - '78 CB750
« Reply #179 on: March 09, 2012, 06:30:55 am »
Yesterday I had NO OIL LEAKS!  So, I put the back end back together, along with the metal inserts I forgot to install in the mudguard's mounting holes last week.  I also got the new Mac 4-2 mufflers installed.  They're gleaming!



I also tucked away the headlight's rat's nest and installed the headlight along with a brand-spanking new chrome headlight ring - looks nice.



My son helped me bleed the front brake - another one checked off!

I had a guy stitch me a new seat cover a few weeks ago, but the attention he paid to the cover did not carry over to the seat pan.  He left a bunch of adhesive and even adhered extra material right atop the paperwork holder!  What a dope.  Anyhow, I need to cut off excess material and clean up the adhesive to make it look nice.  That's in the plans for today.

The tank emblems were painted Tuesday.  Now, I need to work on them some in preparation for clearing them Sunday or Monday.

In addition to those, here's what I still have to do before I can push START!

1.  Install airbox
2.  Install petcock and fuel cap door on tank
3.  Hook up throttle and choke cables
4.  Install tank and side covers
5.  Add fork oil
6.  Bleed front brake
7.  Adjust front brake
8.  Remove/replace rear wheel to install crush washer on rear oil line
9.  Cross fingers
10. Hit START!!


Offline theofam

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Re: Paddy - '78 CB750
« Reply #180 on: March 09, 2012, 08:11:54 pm »
In addition to removing unnecessary fabric under the seat and cleaning up excess adhesive on the seat pan, I also had my son help me align the front forks today.

I wasn't happy with the rust and spotty paint on the air box's mounting brackets, so I painted them:



The tank emblems are now ready for a clear coat:



I also noticed the kill switch isn't working.  It's allowing the starter to operate regardless of whether the switch is in the Off or Run position.  So, I need to troubleshoot that, too.  Off with yesterday's installed headlight!

Maybe Monday is my day to hit START!

Offline MoMo

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Re: Paddy - '78 CB750
« Reply #181 on: March 09, 2012, 08:16:51 pm »
Emblems look good, did you use a paint pen?  The kill switch probably has the detents worn away, a pain to fix especially if one has short little stubby fingers like me, plus you will need a spare red knob...Larry
« Last Edit: March 10, 2012, 12:58:53 am by MoMo »

Offline theofam

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Re: Paddy - '78 CB750
« Reply #182 on: March 09, 2012, 09:07:08 pm »
MoMo, on the emblems, I sandblasted them.  Painted them gold followed by black then today I used lacquer thinner and Q-Tips on the face of the letters.

I was supposed to paint numerous (probably 6+) coats of gold first so as to not eat through to the base metal with the lacquer thinner, but I was only able to lay down three coats earlier this week.  So, the thinner went down to the metal.  What you see is a black background with metal showing on the letters.  I'm still going to try to clear coat it and see if it adheres.

If not, since this is my second botched attempt at restoring the emblems, I'll be on the hunt for some NOS or restored emblems.

Just last week I reassembled the switches after having them powder coated.  I guess I'll tear the switch apart again and see if I can figure out the detents you mentioned.  Why isn't anyone making those dang red spare knobs?  Seems like a plastic mold could be made and those things would sell by the bucket load!!

Your name "MoMo" cracks me up every time I see it.  My now-14-year-old son would point at bikes when he was a toddler and say "Momo! Momo!" as they passed by.  I tried to get a personalized tag here in Colorado back in 1999 reading MOMO, but someone already grabbed it!

Offline MoMo

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Re: Paddy - '78 CB750
« Reply #183 on: March 10, 2012, 01:04:05 am »
The name MoMo cracked me up when I first heard it so I decided to adopt it. Interested in MOtorcycles and my last name is MOulder so it kind of fits. I first heard it used as a real first name during last years NCAA playoffs.  Good luck with the switch, hardest part is putting the little E-clip back on the knob.  I think Yamiya sells the knob...Larry

Offline theofam

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Re: Paddy - '78 CB750
« Reply #184 on: March 10, 2012, 09:49:57 am »
AH-HA!  MoMo, I just noticed you're the old "Photolar."  I couldn't figure why I hadn't heard of you, yet you had 1800+ posts!

I'm off to try and knock the front brake adjustment and fork oil items off the to-do list - getting close!!

Offline Stev-o

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Re: Paddy - '78 CB750
« Reply #185 on: March 10, 2012, 10:21:10 am »
This project is really coming along and looking good! Looking forward to hearing about hitting the start button...
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline MoMo

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Re: Paddy - '78 CB750
« Reply #186 on: March 10, 2012, 12:00:27 pm »
AH-HA!  MoMo, I just noticed you're the old "Photolar."  I couldn't figure why I hadn't heard of you, yet you had 1800+ posts!

I'm off to try and knock the front brake adjustment and fork oil items off the to-do list - getting close!!


Like the photo industry photolar has become oblivious,  and extinct...Larry
« Last Edit: March 10, 2012, 08:13:31 pm by MoMo »

Offline theofam

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Re: Paddy - '78 CB750
« Reply #187 on: March 10, 2012, 06:15:15 pm »
Thanks, Stev-O!

Here's the latest list.  I've added a 1A, which is to troubleshoot the kill switch.  I can almost smell the exhaust fumes!

1.  Install airbox
1A.  Troubleshoot kill switch
2.  Install petcock and fuel cap door on tank
3.  Hook up throttle and choke cables
4.  Install tank and side covers
5.  Add fork oil
6.  Bleed front brake
7.  Adjust front brake
8.  Remove/replace rear wheel to install crush washer on rear oil line
9.  Cross fingers
10. Hit START!!

Offline Stev-o

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Re: Paddy - '78 CB750
« Reply #188 on: March 10, 2012, 07:00:33 pm »
I just went back and read page 1 of this thread, didnt remember that I bought my K7 the same time as you bought Paddy. But you're nearly done and I've done nothing! (except buy 7 more SOHC Hondas since then). Once my current K5 project is done, the K7 is up.

The reason I went back and read is to find out if you ever tried to start it? No, right?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline theofam

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Re: Paddy - '78 CB750
« Reply #189 on: March 11, 2012, 09:14:57 pm »
Stev-O, yep, I had Paddy up and running from April to September. I got him on the road in order to run Godzilla around Colorado.  Then I grew tired of the amount of oil he was consuming, so I tore him down for Round 2. Turned out a $1 puck in the head was faulty - a lot work and $ to remedy a simple item, but Paddy'll look great for St. Paddy's Day!

Offline theofam

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Re: Paddy - '78 CB750
« Reply #190 on: March 12, 2012, 07:42:26 pm »
I got the tank put together today, replete with new warning sticker!  Looks super schweeet!



The air box brackets are painted and it has been cleaned up with Mother's Back to Black.



Ready for install - PSYCH!

I blew the day incorrectly interpreting Honda engineers' intent on use of the kill switch.  I tore the right switch apart - many times - trying to figure out why the kill switch in the Off position allows the starter to spin. Four hours later it came to me . . . The kill switch only kills power to the coils. It has no bearing whatsoever on the starter. I kept seeing exactly that on the wiring diagram, but it didn't register until I intensely noodled and tested the kill switch. DANGIT, I could have had Paddy running today if I were smarter. 

Dumb hurts.

Skiing tomorrow.  Should have a runner Wednesday.


Offline Stev-o

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Re: Paddy - '78 CB750
« Reply #191 on: March 12, 2012, 08:16:33 pm »
Tank looks awesome, love that color.  Where ya skiing?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline theofam

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Re: Paddy - '78 CB750
« Reply #192 on: March 12, 2012, 09:49:24 pm »
Mary Jane - best bumps in the US!

Offline apostrophe28

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Re: Paddy - '78 CB750
« Reply #193 on: March 12, 2012, 09:55:09 pm »
slick looking tank!
1977 750k

Offline Stev-o

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Re: Paddy - '78 CB750
« Reply #194 on: March 13, 2012, 01:24:48 am »
Mary Jane - best bumps in the US!

Yep, been there. How was it? I've always avoided going during Spring Break, hate lift lines.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline theofam

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Re: Paddy - '78 CB750
« Reply #195 on: March 13, 2012, 06:58:49 pm »
Thanks, Apostrophe28!  I'm hoping to have it on Paddy tomorrow if all goes well.  I'm going to re-route the wiring harness tomorrow, but that shouldn't take too long.  Then, on with the tank to test the accelerator pump, off with the tank to install the air box, on with the tank, cross fingers and HIT START!  Oh, yeah, between cross fingers and HIT START I need to set up the camcorder on a tripod to get a video for Stev-O!

Stev-O, the bumps were tough early this morning, but it was over 50 degrees up there today, so they softened up considerably by 11am.  Super nice, though a bit rocky, after that.  Very cool that you've skied that hill!  The Winter Park app on a friend's iPhone claimed a max speed of 195MPH!  So, either we're much quicker than we realized, or the app needs some work.


Offline Stev-o

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Re: Paddy - '78 CB750
« Reply #196 on: March 13, 2012, 07:46:12 pm »
195...Ha!  I'm sure you had a good time regardless. Record spring heat, heard Denver hit 72.
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline theofam

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Re: Paddy - '78 CB750
« Reply #197 on: March 14, 2012, 08:56:34 pm »
ARGHH!! Some days you recede instead of progress.

I moved the wiring harness from the outside of the left top tube to between the left and right top tubes.  It's a lot cleaner and won't risk showing beneath the left side of the tank.



I clear coated the emblems:



Then things started going sideways. 

The throttle was hanging - wouldn't snap back.  I disconnected the push and pull throttle cables, pulled apart the right switch - AGAIN!! - and cleaned/sanded the handlebar as well as the inside of throttle tube.  It was rolling fine on the handlebar, so I reinstalled everything.  DANGIT - still hanging up.  Hmm.  I moved the switch about 1mm toward the end of the handlebar, and, it worked great!  It turned out the throttle tube's butt was dragging against the end of the handlebar.  Friction bad.

Time for the tank, fuel line, half a gallon gas, and only carbs 2 & 3 were squirting via the accelerator pump.  1 & 4 weren't working.  Off came the carbs.  Off came the fuel lines interconnecting the carbs, and I blew them out with some carb cleaner.  To accommodate my poor memory, I also pulled off a carb bowl in an effort to recall the main jets - 110s.

Why is the smell of gas so overwhelming in the garage?  I peeked over to the tank only to notice the petcock piddling!  :o >:( ???  One of many maladies associated with 77 and 78 750Ks is their petcock.  No rebuild kits available.  In fact, I was ticked, because less than a year ago I had fixed this very issue by drilling out the original petcock's rivets, tapping the petcock body, flipping the four-hole rubber grommet and using mini allen bolts in place of the rivets.  So, the petcock is again in pieces:



As the tank looks on:



All that plus a call from the Honda shop that my tank clips to hold on the chrome accent strips were ready for pick up.  Dropped what I was doing, went to the shop, came home ready to install the strips - 6 of 8 clips in the bag.   ???  A call back to the shop and, "Oh.  Um, yep, the system shows two more are still on their way.  If we don't call you, check back in a few days.  They may be here."  Great.

So, here's to hoping tomorrow is a better day.  I plan on dropping by my local salvage yard.  They carry some new parts, and I've fingers crossed I can get that rubber grommet for the petcock.  If not, plan B is to order one from Honda, which means Paddy won't be ready for St. Paddy's Saturday. 

Wish me luck!

Offline MoMo

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Re: Paddy - '78 CB750
« Reply #198 on: March 14, 2012, 09:15:31 pm »
Tank looks great but why isn't it green ::)  Hope better days are ahead...Larry

Offline theofam

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Re: Paddy - '78 CB750
« Reply #199 on: March 15, 2012, 07:59:38 am »
MoMo, I'm thinking green is definitely in order on Seamus (my CB550 that's been sitting long enough I think it has concluded it'll never run again).  Or, I might paint his tank a Guinness black/brown with cream-colored accents.

I'm getting WAY ahead of myself!  First, I need to get Paddy up and running.