Author Topic: No more stupid main jet leaf springs!  (Read 12962 times)

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Offline davis96

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No more stupid main jet leaf springs!
« on: February 03, 2012, 09:41:29 am »
My carbs were missing 2 of the main jet retaining leaf springs and the other 2 were withering away from rust. I made 2 new ones from a hacksaw blade, and that worked until one of them broke in half. Frustrated, I devised a new method to hold the main jets in place. Not trying to re-invent the wheel here, but as we all know, those little leaf springs are not available in the aftermarket and only pop up on eBay once in a great while. So here's what I came up with:

I cut a washer on one side, then slipped it on the unused upper main jet groove, and clamped it so it won't come off. This washer provides the place for a coil spring to sit, performing the same function as the factory leaf spring type retainer. So far so good as far as functionality is concerned.
'74 CB350F - sold
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Offline ekpent

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Re: No more stupid main jet leaf springs!
« Reply #1 on: February 03, 2012, 09:51:27 am »
Be nice if you can find them in stainless or brass if rust is a problem. Not familiar with those carbs,never had any but hope it works out well for you and helps others. A sorta spring of a different sort.

Offline Tugboat

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Re: No more stupid main jet leaf springs!
« Reply #2 on: February 03, 2012, 12:26:16 pm »
Great idea! Got a picture of the side where you cut the washer? And what do you mean by "clamped"?
If it's worth doing, it's worth doing twice.

Offline mrrch

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Re: No more stupid main jet leaf springs!
« Reply #3 on: February 03, 2012, 01:50:25 pm »
Great idea, would an e-clip work?
my build

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Offline Frostyboy

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Re: No more stupid main jet leaf springs!
« Reply #4 on: February 03, 2012, 04:31:04 pm »
I cut a washer on one side, then slipped it on the unused upper main jet groove, and clamped it so it won't come off. This washer provides the place for a coil spring to sit, performing the same function as the factory leaf spring type retainer. So far so good as far as functionality is concerned.
What an excellent idea. Congratulations on thinking outside the box. Is the spring a snug enough fit so it doesn't fall off when the carbs are still on the bike with the bowl removed?
Are you able to supply the source of the springs?

Great idea, would an e-clip work?
It just gets better.
This should be listed in 'Tricks & Tips'
« Last Edit: February 03, 2012, 04:32:36 pm by Frostyboy »
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Offline Gordon

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Re: No more stupid main jet leaf springs!
« Reply #5 on: February 03, 2012, 04:48:40 pm »
I cut a washer on one side, then slipped it on the unused upper main jet groove, and clamped it so it won't come off. This washer provides the place for a coil spring to sit, performing the same function as the factory leaf spring type retainer. So far so good as far as functionality is concerned.
What an excellent idea. Congratulations on thinking outside the box. Is the spring a snug enough fit so it doesn't fall off when the carbs are still on the bike with the bowl removed?
Are you able to supply the source of the springs?

Great idea, would an e-clip work?
It just gets better.
This should be listed in 'Tricks & Tips'

Agreed!  I'll put it there now. :)

Offline davis96

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Re: No more stupid main jet leaf springs!
« Reply #6 on: February 03, 2012, 11:41:41 pm »
I cut a washer on one side, then slipped it on the unused upper main jet groove, and clamped it so it won't come off. This washer provides the place for a coil spring to sit, performing the same function as the factory leaf spring type retainer. So far so good as far as functionality is concerned.
What an excellent idea. Congratulations on thinking outside the box. Is the spring a snug enough fit so it doesn't fall off when the carbs are still on the bike with the bowl removed?
Are you able to supply the source of the springs?

Great idea, would an e-clip work?
It just gets better.
This should be listed in 'Tricks & Tips'

Great idea! Got a picture of the side where you cut the washer? And what do you mean by "clamped"?

Hope this picture explains what I did somewhat:

An e-clip would be ideal but I just used what I had lying around.. As for the springs, I bought a pack of assorted springs a while back.. the jets are very snug once the bowls are installed, but there's no chance everything would stay in place upside down
'74 CB350F - sold
'71 CB500K

Offline HondanutRider

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Re: No more stupid main jet leaf springs!
« Reply #7 on: February 04, 2012, 05:34:14 am »
GREAT SOLUTION AND ILLUSTRATION DAVIS!!!!

Offline Frostyboy

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Re: No more stupid main jet leaf springs!
« Reply #8 on: February 04, 2012, 06:50:03 am »
+1 on the illustration, great work.
Perhaps a little crimping of the first coil on the spring might grip onto the jet to hold it in place to allow bowl removal on the bike if there was a need to?
Last year I joined a support group for procrastinators.
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Offline dave500

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Re: No more stupid main jet leaf springs!
« Reply #9 on: February 05, 2012, 12:56:38 am »
i think its a great idea,,and too simple when you think about it.

Offline MoMo

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Re: No more stupid main jet leaf springs!
« Reply #10 on: February 05, 2012, 02:01:11 am »
GREAT SOLUTION AND ILLUSTRATION DAVIS!!!!



Ditto to that!  ...Larry


Offline crazypj

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Re: No more stupid main jet leaf springs!
« Reply #11 on: April 11, 2012, 08:55:20 am »
Just saw link to this post.
 Great idea, I wish I'd thought of it first  ;D
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Offline 73cb500

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Re: No more stupid main jet leaf springs!
« Reply #12 on: February 20, 2013, 06:21:28 pm »
Be nice if you can find them in stainless or brass if rust is a problem. Not familiar with those carbs,never had any but hope it works out well for you and helps others. A sorta spring of a different sort.
how has this worked out i have the same problem my leaf springs are almost rusted in half that is an awesome idea also you got any tips on rebuildint these carbs

Offline crazypj

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Re: No more stupid main jet leaf springs!
« Reply #13 on: February 21, 2013, 07:07:20 am »
I've done a couple of CB350 carbs for people, no complaints yet
 It's a simple solution for a common problem
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Offline blakes1975

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Re: No more stupid main jet leaf springs!
« Reply #14 on: August 15, 2013, 05:49:32 pm »
Great answer to my q&a.  Were did you get the springs?

Offline davis96

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Re: No more stupid main jet leaf springs!
« Reply #15 on: September 17, 2013, 01:34:37 pm »
Great answer to my q&a.  Were did you get the springs?
IIRC, I bought a package of assorted springs at Home Depot
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Offline francis8766

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Re: No more stupid main jet leaf springs!
« Reply #16 on: April 16, 2014, 01:40:14 am »
Hi. . Can anyone post the ilustration again because its not in the thread anymore. Thanks guys
1975 honda cb550f

Offline dave500

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Re: No more stupid main jet leaf springs!
« Reply #17 on: April 16, 2014, 02:07:39 am »
I still see the picture.

Offline LesterPiglet

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Re: No more stupid main jet leaf springs!
« Reply #18 on: April 16, 2014, 03:29:01 am »
Weird, it says image deleted.
'Then' and 'than' are completely different words and have completely different meanings. Same with 'of' and 'have'. Set and sit. There, their and they're. Draw and drawer. Could care less/couldn't care less. Bought/brought FFS.


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Offline HondanutRider

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Re: No more stupid main jet leaf springs!
« Reply #19 on: April 16, 2014, 04:51:04 am »
It also says "deleted" for me.  So here's a copy of Davis' great picture that I saved:

Offline grcamna2

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Re: No more stupid main jet leaf springs!
« Reply #20 on: April 16, 2014, 11:22:40 am »
Thanks for posting that picture of the main jet washer 'clamping' hondanutrider.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
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Offline dave500

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Re: No more stupid main jet leaf springs!
« Reply #21 on: April 16, 2014, 12:38:03 pm »
the first post has a photo.

Offline francis8766

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Re: No more stupid main jet leaf springs!
« Reply #22 on: April 19, 2014, 08:49:34 am »
Thanks for uploading the illustration  :)
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Offline swan

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Re: No more stupid main jet leaf springs!
« Reply #23 on: May 28, 2014, 07:36:40 pm »
Thanks Davis 96 for the idea. I went to the hardware store and came up with this for my CB400F. It works brilliantly.

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Offline lucky

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Re: No more stupid main jet leaf springs!
« Reply #24 on: June 13, 2014, 11:18:00 am »
Be nice if you can find them in stainless or brass if rust is a problem. Not familiar with those carbs,never had any but hope it works out well for you and helps others. A sorta spring of a different sort.

Do not use brass next to the aluminum if you can avoid it.
Even the original 1969-70 carbs had aluminum mixture screws
and aluminum float bowl drain screws.

Stainless is a much better choice.