Author Topic: Dorothy III - CB750  (Read 103667 times)

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Offline 70CB750

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Re: Dorothy III - CB750
« Reply #500 on: July 09, 2024, 04:27:52 AM »
You gotta love the 1,001 uses for angle iron! Such a versatile material shape.

Exactly.
Prokop
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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 #501 on: July 09, 2024, 04:36:02 AM »
Truing the wheel I started to freak out.  It seemed like I will never get it right.

This morning  I took a dial indicator to see how bad it was.

0.74 mm axial and 1.2mm radial.  I can live with that.   :)

For the kicks I checked the old rim from Dorothy. 2.7 mm and 1.35mm.
Prokop
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I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline grcamna2

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Re: Dorothy III - CB750
« Reply #502 on: July 09, 2024, 07:05:54 AM »
Prokop,have a look at putting the pointer inside the rim,along the bead area;that area is the most accurate.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
Do your BEST...nobody can take that away from you.

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #503 on: July 09, 2024, 07:46:20 AM »
Prokop,have a look at putting the pointer inside the rim,along the bead area;that area is the most accurate.

Thats what i did.
Prokop
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I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline BenelliSEI

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Re: Dorothy III - CB750
« Reply #504 on: July 10, 2024, 06:32:54 AM »
Still truing the rim.  Finally made me a truing stand.
[/quote

How do you stop the axle from shifting left or right?

P.S. I pulled two old metal bed frames out of a scrap bin last week. Great source of free material!

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #505 on: July 10, 2024, 07:08:30 AM »
I pulled many things from the scrap bin - even though it is illegal in our county.

I wrapped masking tape on the axle and that helped.   For the final check I held the axle and let it spin on wheel bearings.

If there is a trick to it, I am all ears, sir.
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

Online MauiK3

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Re: Dorothy III - CB750
« Reply #506 on: July 10, 2024, 07:52:13 AM »
Frustrating, are the bearings ok?
1973 CB 750 K3
10/72 build Z1 Kawasaki

Offline grcamna2

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Re: Dorothy III - CB750
« Reply #507 on: July 10, 2024, 08:19:20 AM »
I pulled many things from the scrap bin - even though it is illegal in our county.

I wrapped masking tape on the axle and that helped.   For the final check I held the axle and let it spin on wheel bearings.

If there is a trick to it, I am all ears, sir.

20-30+ yrs. ago persons could walk around the county landfill areas without anyone telling them 'that's against the rules'. Very upsetting how they have messed things up now.
Prokop,what's their reason for saying it's illegal to remove an item ?
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
Do your BEST...nobody can take that away from you.

Offline calj737

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Re: Dorothy III - CB750
« Reply #508 on: July 10, 2024, 08:20:50 AM »
I pulled many things from the scrap bin - even though it is illegal in our county.

I wrapped masking tape on the axle and that helped.   For the final check I held the axle and let it spin on wheel bearings.

If there is a trick to it, I am all ears, sir.
What you could have done, is move the rollers to the inside of the angle iron at the proper width of the axle spacer to hold the rim/hub centrally. Then lateral movement would have been restricted. But tape works perfectly well for the tolerances you need and you achieved even better than necessary truing.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #509 on: July 10, 2024, 11:09:58 AM »
I pulled many things from the scrap bin - even though it is illegal in our county.

I wrapped masking tape on the axle and that helped.   For the final check I held the axle and let it spin on wheel bearings.

If there is a trick to it, I am all ears, sir.

20-30+ yrs. ago persons could walk around the county landfill areas without anyone telling them 'that's against the rules'. Very upsetting how they have messed things up now.
Prokop,what's their reason for saying it's illegal to remove an item ?


There used to be trash-to-treasure sharing area at the landfill but some people would hang there all weekend to get items for yard sales and such.  Now you can leave it and it gets donated to a local thrift store and money from the sale goes to the county food bank.

But once you drop it in the trash or recycling container, it belongs to the county and it is illegal to take it. 

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 #510 on: July 10, 2024, 11:12:22 AM »
I pulled many things from the scrap bin - even though it is illegal in our county.

I wrapped masking tape on the axle and that helped.   For the final check I held the axle and let it spin on wheel bearings.

If there is a trick to it, I am all ears, sir.
What you could have done, is move the rollers to the inside of the angle iron at the proper width of the axle spacer to hold the rim/hub centrally. Then lateral movement would have been restricted. But tape works perfectly well for the tolerances you need and you achieved even better than necessary truing.

Gotit, thanks.  I will make some shaft collars when I have time to play with it.
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 #511 on: August 20, 2024, 05:55:32 AM »
Borrani going tubeless.  I used 3M 5200 glue to seal nipples in and it will get covered by special tape. 
« Last Edit: August 20, 2024, 07:17:59 AM 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 calj737

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Re: Dorothy III - CB750
« Reply #512 on: August 20, 2024, 07:09:55 AM »
Have you seen the “foam core” used on newer bicycles for spoked tires? It makes the tire tubeless, plus adds some amount of protection during tire compression. I don’t know whether they have any in 19/18” diameters, but the concept is pretty good.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline 70CB750

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Re: Dorothy III - CB750
« Reply #513 on: August 20, 2024, 07:18:30 AM »
Have you seen the “foam core” used on newer bicycles for spoked tires? It makes the tire tubeless, plus adds some amount of protection during tire compression. I don’t know whether they have any in 19/18” diameters, but the concept is pretty good.

I did not know that, will check it out. 
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 #514 on: October 03, 2024, 06:19:20 AM »
From Suzuki for Honda  :)
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 Stev-o

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Re: Dorothy III - CB750
« Reply #515 on: October 03, 2024, 07:23:57 AM »
Suzuda?!
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline calj737

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Re: Dorothy III - CB750
« Reply #516 on: October 03, 2024, 07:44:35 AM »
Looks like you are planning some “fabrication” on that arm? Pivot tube and front brace? A word of caution, if you weld that coved brace onto that pivot tube and arms, it will tend to pull that tube out of square (straight, alignment to the arms). Best to weld that tube last after the arms and brace are constructed and cooled. Then you have a better chance to avoid any distortion to the tube alignment.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline Mark1976

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Re: Dorothy III - CB750
« Reply #517 on: October 03, 2024, 07:45:40 AM »
Start with the end in mind...

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Re: Dorothy III - CB750
« Reply #518 on: October 03, 2024, 07:46:52 AM »
Welding is so much art and science all rolled up
1973 CB 750 K3
10/72 build Z1 Kawasaki

Offline Stev-o

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Offline calj737

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Re: Dorothy III - CB750
« Reply #520 on: October 03, 2024, 02:06:44 PM »
Welding is so much art and science all rolled up
A lot of truth in that statement. The “art” is understanding stress, distortion, and sequence. The science is about understanding penetration, weld joints, configurations, and settings.
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis