Author Topic: No more stupid main jet leaf springs!  (Read 1557 times)

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Online davis96

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No more stupid main jet leaf springs!
« on: February 03, 2012, 11:41:29 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.
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'71 CB500K - super budget build in the works



Offline ekpent

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Re: No more stupid main jet leaf springs!
« Reply #1 on: February 03, 2012, 11:51:27 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, 02:26:16 PM »
Great idea! Got a picture of the side where you cut the washer? And what do you mean by "clamped"?



Offline mrrch

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Re: No more stupid main jet leaf springs!
« Reply #3 on: February 03, 2012, 03:50:25 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, 06:31:04 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, 06:32:36 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, 06:48:40 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. :)



Online davis96

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Re: No more stupid main jet leaf springs!
« Reply #6 on: February 04, 2012, 01:41:41 AM »
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 - super budget build in the works



Offline HondanutRider

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Re: No more stupid main jet leaf springs!
« Reply #7 on: February 04, 2012, 07:34:14 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, 08:50:03 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?
The only Aussie to get into the 500 Mile Club for the 2011 World Tour.
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Offline dave500

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Re: No more stupid main jet leaf springs!
« Reply #9 on: February 05, 2012, 02:56:38 AM »
i think its a great idea,,and too simple when you think about it.
that "thing"happens to be a HONDA 500 FOUR!



Online MoMo

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Re: No more stupid main jet leaf springs!
« Reply #10 on: February 05, 2012, 04:01:11 AM »
GREAT SOLUTION AND ILLUSTRATION DAVIS!!!!



Ditto to that!  ...Larry

Present: 1975 CB750, two 1974 CB750's, 1975 CB400 four,  1981 GL500I, 1974 CZ 250 Enduro, 1966 Suzuki S32 150cc , 1977 CB750K7, 1974 Honda XL125K0, 1983 Honda Sabre, , more to come.

Past: Honda XL125 I rode in enduros, Honda XL175, Yamaha DT1, MZ 250 ISDT, Harley Hummer, 1969 Honda CB350, 125 Sachs/DKW, 250 Ossa Pioneer, 1968 250 Montesa La Cross, Yamaha RD350, two Yamaha TX500, eight Honda CB450 dohc, 250 KTM, 1982 Yamaha 650 four(worst bike ever owned), seven Honda CB400f's, 1983 Honda VF750F Interceptor, 1981 CB650, 1973 CB350G, 1973 CB750, mint 1975 Honda CB550F, 1977 CB750K , GL500I Silverwing, 1973 Jawa 175 Trailmaster, SL350 K2, 1970 CB750K0, 1972 CB350 and  probably others long forgotten.



Offline crazypj

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Re: No more stupid main jet leaf springs!
« Reply #11 on: April 11, 2012, 10:55:20 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, 08:21:28 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, 09:07:20 AM »
I've done a couple of CB350 carbs for people, no complaints yet
 It's a simple solution for a common problem
I fake being smart pretty good
'you can take my word for it or argue until you find out I'm right'

 

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