Author Topic: Fixing float tower  (Read 578 times)

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Offline JTknives

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Fixing float tower
« on: December 01, 2018, 01:05:45 pm »
I know I’m new here but I thought I would share my fix I did. Im not a bike guy but I am attempting to rebuild a CB500 into a cafe. I’m a machinest by trade so that’s where I come from in approaching this fix.
This carb had been busted by the previous owner I assume. It was held in place with JB weld. After soda blasting the jbweld was gone and the little post was not attached anymore. I had considered welding but there was a part of the post missing so it had to be replaced. Hope this helps someone else.

Clamp the carb down to the mill table

Mill the remaining stub off flush with the gasket surface.

Using the same endmill I plung cut down 1/4” (.25).

Then I used the lathe to turn a replacement post with a stepped shoulder. This stepped down area was about .002 over the size of the hole I created in the carb.

Here it is parted off and ready for fitting. I cooled the pin in liquid nitrogen and heated the carb in the oven. Then quickly I set the pin into the hole and gave it a gentle tap.

And here it is ready to be drilled for the float pin


Online calj737

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Re: Fixing float tower
« Reply #1 on: December 01, 2018, 02:43:19 pm »
Excellent remedy, and workmanship.
'74 550 Build
'73 500 Build

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Offline BobbyR

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Re: Fixing float tower
« Reply #2 on: December 01, 2018, 06:40:29 pm »
Terrific tutorial. Very few of us have that equipment or expertise. Will you be offer this as a service.
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline slikwilli420

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Re: Fixing float tower
« Reply #3 on: December 03, 2018, 11:38:20 am »
I have a busted one on a set Im working on now. If I cannot get it welded properly I will have to try this out.
All you gotta do is do what you gotta do.

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Online carnivorous chicken

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Re: Fixing float tower
« Reply #4 on: December 03, 2018, 02:18:33 pm »
Very tight work!

Offline Can550

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Re: Fixing float tower
« Reply #5 on: December 03, 2018, 03:08:06 pm »
Amazing workmanship
Who knew back in 70s one day such ordinary stuff will receive such great deal of attention to put back in service
Good job

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