Topic: Paddy - '78 CB750 - Version 3.0 Coming Soon!

[lucky]

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!    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!

These carbs in the photo are missing the restricter tubes in the accelerator pump circuit going to each carb nozzle!!!

We should see them inside the pink plastic fuel tubes.

They are inside the black rubber hoses that came on the carbs from the factory. Do you still have them?

[Stev-o]

Theo - where ya been?!

Leave it to Lucky to bring back this thread.

[theofam]

Lucky, I may need to buy you a beer!  I've been scratching my head over the past 1.5 years about my accelerator pump's lack of . . . well . . . pumping accelerated fuel when I open the throttle.  If it's as simple as putting some brass tubes into my clear tubing connecting my accelerator pump channels between carbs, I'll be super excited! Regardless, thank you for your attention to detail.

Stev-O, I've been dormant far too long.  When you chimed in back in July, I was on the ride of a lifetime with my dad.  I can't believe I was fortunate enough to do a trip like that.  Get home, kids back into school, yada, yada, Holidays, and here we are.  I'm back on it!

I wanted to button up Paddy's motor today, but I'm missing a stinkin' dowel (see finger):



It's ordered and on the way.  Once I get the valve cover on, I'll get the motor in and start bolting parts back onto Paddy!  I've also a surprise acquired since the first two builds I can't wait to unveil!

I'll start getting pics up again (hopefully starting next week).  Hope you're well!

[brandEn]

Make sure that dowel isn't stuck in the valve cover. That happened to me!
 
Nice to see ya back on this.

[theofam]

BrandEn, where do you think I got the other dowel?!

I'm glad to be back on it, too!  I miss all you guys and have enjoyed getting caught back up on the site over the past week.  So many cool projects and workmanship - definitely humbling to see the creativity and quality.

Hope your 2013's off to a great start!

[Jerry Rxman Griffin aka MuthaF'er]

Maybe we can take them BOTH all the way up PAVED P.P. Highway now... when it warms up 

[theofam]

Jerry,  I'd love to go up Pikes Peak again!  Paddy 1.0 was running so great at 11,000 feet (see avatar), I'm convinced he'd pull strong all the way to 14,114!

Are you overseeing GZ 3.0 in 2013?  I'd like to take Godzilla around this year after missing 2012.  Let's stay in touch and ride as the weather improves.

[Jerry Rxman Griffin aka MuthaF'er]

IMO 2013 GZ is looking like a bust??!! I haven't any plans.

[Stev-o]

IMO 2013 GZ is looking like a bust??!! I haven't any plans.

Don't say that Jerry! It will just be different, I plan to contact Wilbur to see if he wants to kick it off.

Good to see you back, Theo.  You should start a thread about your bike trip.

[theofam]

Stev-O, I did a ride report of my Arctic Circle trip over on advrider.com.  Here's the link:

http://advrider.com/forums/showthread.php?t=803114

Jerry, although it'd be too bad if GZ 3.0 didn't happen, to think a group of world-wide riders coordinated relaying a piston-waving, beer-swizzlin', plastic Godzilla for TWO YEARS is pretty amazing!!

[RustyOlive]

Well informative thread Theo.

Keeping an eye on this one as well. :-)

[theofam]

Paddy 3.0 is coming along.  My son helped me get the motor in Sunday - it was a b#$%^!  I opted for the hang-the-engine-from-a-2x4-suspended-by-jackstands method and slid the bike over to the engine.  It sucked.  45 minutes later and a couple powdercoat scratches  , and it was in.



Today I was able to:

• install spark plugs and wires
• secure all engine mounts and rider pegs
• attach tach cable
• install rear brake switch
• connect ignition wires
• connect neutral switch wire
• install oil tank and lines
• install oil filter housing
• attach and route all smog control lines
• install chain and **SWEETLY POLISHED** sprocket cover

It's getting there!



Tomorrow I'm planning on installing restrictor tubes in the carbs' accelerator pump's lines.  As Lucky pointed out above, I'm missing them, which I hope explains the sluggishness I experienced with Paddy 1.0 and 2.0 off idle.  I picked up the brass tubing and tube cutter at a hobby shop and have them cut.  The pink tubing between the carbs is already brittle, so I'm going to pick up some fresh tubing tomorrow.  I'll post progress tomorrow night.

[Stev-o]

Alright!  Looks good and a lot of progress, we've been waiting.

[theofam]

Stev-O, I was on here three weeks ago saying I'd have the engine installed in a week - nope!  It took two weeks to get two dowels and an o-ring delivered, a week to button up the motor, and now I'm back on it - feels good.  I've a block of six hours tomorrow, so I'm hoping to get quite a bit checked off the list.  Hope you're doing well!

[Jerry Rxman Griffin aka MuthaF'er]

Looking forward to riding ALL THE WAY TO THE TOP with you on 2 new bikes soon. I still have break-in and fine tuning to do once I find a dyno tune shop.

[theofam]

Jerry, I'm looking forward to Pikes Peak, too!  Can't wait to see dyno numbers from your big hoss!

[flybox1]

that color of your tank is nice!! 
brass carb tube restrictors really improved my cold starts and off idle (and a new choke cable/properly tuned fast idle cam)
on the bench, my #4 wasn't getting a good shot of fuel through the pump system.
brass inserts really made a pressure difference at the far end.

[theofam]

flybox1,

Thanks for the compliment on the tank.  I like the way it turned out, but it's nowhere near the brownish-red color of a stock '78.  Oh well, I guess that makes Paddy more unique.

My #4 carb's accelerator pump nozzle has always had a weak spray.  I'm really excited to hear the brass inserts helped you with that issue - fingers crossed they help me, too.

For anyone looking to do this, here are the specs from flybox1:

In each connector tube, there are two.  One short, one long. 

.35" & .45"
OD is 3/16"(5mm)
ID is 11/64 (4.5mm)

Here are the supplies - brass tubing (you see two cut pieces in the pic), tube cutter, and fuel line:



flybox1 recommended I pick up the brass tubing at a hobby store, which is exactly where I found it (Colpar Hobbies in Aurora, Colo.).  Like the tube cutter, the tubing is from a company called K&S.  You can probably order it online if you can't find it locally.

I used a hair dryer to warm up the fuel line:



Then used remaining brass pipe to center the two pieces in the fuel line:



Cutting the pieces took me about 20 minutes, the above portion about 10 minutes, and, I'm done!



Gotta go - Paddy's calling for me to get back to the garage!  He's pretty excited to take me up Pikes Peak with Jerry.   

[theofam]

I mentioned Paddy 3.0 would have a surprise - here it is!

KABOOM



In August, I was sitting next to my wife as she watched yet another crime drama (I think they're like watching paint dry), so I figured I'd fire up craigslist to see if any gems were advertised.  I was stunned, excited, giddy even, when I found an ad for a set of dang-near pristine HM405 pipes!  I'd watched ebay over the last couple years, but I couldn't bring myself to pay $800-$1000 for a new set.  Didn't have to - $200!!!



I was a bit bummed as I polished them today.  I found a small dent.  An hour later during install, I realized the dent was intentional for the rear brake - SCHWEET!



Got the carbs and airbox on, too.



If the motorcycle gods are on my side tomorrow, I'll be able to get the throttle cables, clutch cable, gear shift, kick starter and rear brake pedal on.  After that, it's tank, seat, fuel and oil - WOOHOO!

[iron_worker]

Wow those pipes were a major score! I paid $1200 for mine...

IW

[Stev-o]

Kaboom - great deal, good for you. Like the CO plate with the mts on it too, you been on the slopes?
It's already spring here, 80* today.

[theofam]

Stev-O, I hit the slopes two weeks ago and am going back up next week. It has been warm here this winter, too, which makes for subpar skiing. I think we're at 60% of typical snowpack, which means lots of wildfires this summer if things don't change in a hurry!

IW, a new set would have been cool, but I can live with these at $200. They're very nice.

More progress on Paddy today. Lots of little bits. Had to pull the clutch cover back off to get the shaft correctly oriented (was thankfully able to save the gasket). I also proved what a bonehead I am by attaching the starter cable directly to the battery. Adding the negative lead gave me a fireworks show and the starter running while the ignition key was in the OFF position. Took me awhile on the forum to understand what I had done wrong!  What a tool.

I just need to add gas and hope the GO button works, top off oil and add side covers!

[Stev-o]

The bike looks fantastic.

[flybox1]

nice work on the tubing. i cant take the credit. got the specs from Lucky when my K8 didnt have them......and the pipes look great. its coming together nicely

[theofam]

Stev-O and flybox1, thanks for the kind words, fellas!

I started Paddy Version 3.0 and . . . he's alive!  He's not running great and needs some tuning, but he runs and revs nicely off idle (flybox1 & Lucky - I attribute that to the tubes)!

I pulled the 1 & 4 exhaust rocker covers, and it appears oil is getting to the top end!  That said, 4's exhaust pipe was noticeably hotter than the others. Maybe running lean on that cylinder?

After running two minutes, I checked the oil tank, and it was dry. I topped it off, but I need to see if it happens again - I really don't like the idea of the scavenge pump not working.  So, I'm hoping that was normal and just a matter of oil being pulled into the engine during its first start.

Side covers are on:



A tune up and some better pics are in order!

In the meantime, I'm REALLY happy to have this dude in the garage: