Author Topic: Dorothy III - CB750  (Read 103623 times)

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Offline 70CB750

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Dorothy III - CB750
« Reply #125 on: August 21, 2012, 06:20:11 AM »
Installed new to me fender, the old one does not fit new forks.
Prokop
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Dorothy - my CB750
CB750K3F - The Red
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CB900C

2006 KLR650

Offline Terry in Australia

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Re: Dorothy III - CB750
« Reply #126 on: August 22, 2012, 12:22:48 AM »
Looking good mate, are you gonna install some dust boots on those forks? You'll get a lot more life outta your fork seals if you do. Cheers, Terry. ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #127 on: August 22, 2012, 04:35:20 AM »
Thanks, Terry.

I keep forgetting, I have some velcro boots from previous owner I have to put on for now.
Prokop
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I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline lucky

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Re: CB750 made in March, 1970
« Reply #128 on: August 22, 2012, 05:47:17 PM »
Checked carburetors and sure enough, number 2 bowl was empty.  The valve the floater holds was stuck.  Took it out, cleaned it and polished with 3M Scotch pad, put it back together, started nicely with choke and now correctly set timing. 

Took it up and down the road several times, runs ok, lost rubber from the left peg.

New issue - oil leak from the seal behind the chain sprocket, gotta change it.  It is a steady drip every second, makes quite a puddle reaaaaaaallly quick.

Block off that chain oiler if it is still there or if it has one.

Offline lucky

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Re: CB750 made in March, 1970
« Reply #129 on: August 22, 2012, 05:54:19 PM »
Found some gunk in carburetor slides, cleaned it with scotchbrite.

Looks like the cable was not the reason of hanging slides,  4 days in a row the bike now starts with choke, warms up and idles nicely around 1000.  It is not perfect yet, before vacuum gauge synchro, but messing with it every day does wonders for my ability to tune the stop screw and air screw.

There was rusty gunk in the petcock bowl, cleaned it out.

Side note:  I landed a job after 9 month, life is great.

Naughty note:  The other day, while sitting on the bike, adjusting stop screws on #2 and #3 and checking for reaction, I realized it reminds me working clitoris, same small finger movements   - now where is the damn G point?  ;D ;D

Those carbs are great.
The best ones. Easy to adjust and to be able to get to everything.
Do not clamp down the throttle cable. It will not work right.
It does not need to be synced.
With those carbs just make sure all of the slides are all the way down and there is no play in the cable. Then make sure that when you pull on the throttle cable that all 4 slides start to move at the same time.
You can put you finger on the slide and turn the throttle to sense exactly when the carb starts to open.

Also make sure that there is no slack in the cable housings between the splitter box and the carbs.

The throttle cable is not routed the best way. I will post a pic of the way to route the cable so that the tank does not interfere with the throttle cable movement.

With these carbs 1/8 turn of the mixture screw makes a difference.
They really respond to adjustment.
You can use the part of the throttle cable between the handlebar and the splitter box to keep the slack out of the cable and actually adjust the idle that way. It stays in adjustment easier that way.

Click once on the photo and you get a larger image.


« Last Edit: August 22, 2012, 05:59:04 PM by lucky »

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #130 on: September 11, 2012, 01:33:24 PM »
Down the hill she developed this skip fire on #2 or 3. Today I looked into it and #2 cable just fell in my hand, looks like it was lose with piece of insulation in the boot.

Cut them all 1/4" shorter and screwed caps in anew.
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #131 on: September 25, 2012, 10:38:59 AM »
3000 miles tune up.  Tappets, carb synch, checked plugs.

Rear tire shows cord, placed an order with Bike Bandit for BT45s front and back.

Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #132 on: September 25, 2012, 10:46:23 AM »
Build new exhaust, bit quieter than the straight pipe with packing.  It runs and idles, will see how it is on the road.

The outer pipe is piece of truck exhaust, the inner pipe is a piece of TV antenna post and the rear ring is attached to the perforated pipe with a piece of old vice - it is handy to be a pack rat :)
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline 70CB750

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Dorothy III - CB750
« Reply #133 on: September 29, 2012, 03:42:01 PM »
New muffler sprayed black - grill paint - and installed.
« Last Edit: September 29, 2012, 03:43:41 PM by 70CB750 »
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline Terry in Australia

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Re: Dorothy III - CB750
« Reply #134 on: September 30, 2012, 01:36:16 AM »
That bike is looking cool mate, and I love that seat, if you ever decide to replace it, I want it! ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #135 on: September 30, 2012, 09:59:09 AM »
Geez Terry, are you serious? It's not just the cover, the pan is broken too. I will be replacing it as soon as I have a new one - you can have this one if you really want it.
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline MCRider

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Re: Dorothy III - CB750
« Reply #136 on: September 30, 2012, 10:33:27 AM »
Geez Terry, are you serious? It's not just the cover, the pan is broken too. I will be replacing it as soon as I have a new one - you can have this one if you really want it.
I kinda agreed with Big T. Its a 70s throwback, doubles as a cafe seat with a bump, or a 2 seater. Corbin-Gentry K&Q?
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

Offline seanbarney41

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Re: Dorothy III - CB750
« Reply #137 on: September 30, 2012, 03:54:50 PM »
I got one of those too, if not, very very similar...yup, it says Corbin on the bottom...iirc
If it works good, it looks good...

Offline seanbarney41

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Re: Dorothy III - CB750
« Reply #138 on: September 30, 2012, 03:58:10 PM »
...or maybe it was this one?
If it works good, it looks good...

Offline Terry in Australia

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Re: Dorothy III - CB750
« Reply #139 on: October 01, 2012, 03:38:58 AM »
Geez Terry, are you serious? It's not just the cover, the pan is broken too. I will be replacing it as soon as I have a new one - you can have this one if you really want it.

Hey thanks mate, you're a good man, but if the base is screwed I'll save my little bag of coins for a better one. I know you probably would have offered it to me for free, but the shipping wouldn't be cheap, so I may as well hang out for a good one. I like SeanBarney's seats too, there are some nice old seats out there, but they're all on your side of the pond! ;D 
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #140 on: October 01, 2012, 05:11:56 AM »
The second picture looks pretty close actually.

The story of the seat is that the rear was supported only by the fender and the fende is cracked  - suppose the seat pan just couldnt hold any longer.
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline seanbarney41

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Re: Dorothy III - CB750
« Reply #141 on: October 01, 2012, 12:31:48 PM »
well, this got my curiosity going, so i had to check last night...the first pic is corbin gentry...the second pic looks to be a pretty nice home fabbed pan with custom upholstery.  All the good, cheap, 1970's superbikes around here seem to have had their seat replaced with some kinda king/queen type o' thing...as a result I seem to be developing quite the collection...thinking about building bar stools (for two up drinkin" :D 8)) or something
If it works good, it looks good...

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #142 on: October 01, 2012, 02:08:39 PM »
Double bar stool?
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline seanbarney41

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Re: Dorothy III - CB750
« Reply #143 on: October 01, 2012, 02:22:26 PM »
yes...every king must have his queen...and vice versa
If it works good, it looks good...

Offline Terry in Australia

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Re: Dorothy III - CB750
« Reply #144 on: October 03, 2012, 03:50:52 AM »
They'd be very popular at the "Blue Oyster Bar", I'd imagine............ ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline seanbarney41

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Re: Dorothy III - CB750
« Reply #145 on: October 03, 2012, 12:19:15 PM »
They'd be very popular at the "Blue Oyster Bar", I'd imagine............ ;D
lol...nuts to butts, man
If it works good, it looks good...

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #146 on: October 14, 2012, 07:45:11 AM »
Rode the bejesus out of her on Godzilla run. At least 8 hours most of it above 4k and stops only for gas and handover. 

She made herself proud!

Side note: the open face helmet sucks and I need better mirrors.
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline Old Scrambler

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Re: Dorothy III - CB750
« Reply #147 on: October 14, 2012, 03:36:27 PM »
OK 8) 8) 8) You are officially a success :) :) :) :) :)
Dennis in Wisconsin
'64 Triumph Cub & '74 Honda CB750 Bonneville Salt Flats AMA Record Holder (6)
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Offline 70CB750

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Re: Dorothy III - CB750
« Reply #148 on: October 15, 2012, 04:46:41 AM »
Thank you, thank you very much.  8)
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #149 on: October 15, 2012, 06:44:12 PM »
My new spin on oil filter adapter.   I bought a slice of 4" diameter aluminum on ebay, the rest is from my scrap metal pile.  The nipple is made from a  steering bar from Chevy Corvette and the nut came from the front wheel spindle of 95 Ford Taurus.   I had to turn the nut down to fit under the filter, but it worked reasonably well.
« Last Edit: October 15, 2012, 06:47:02 PM by 70CB750 »
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650