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> How to make your CB carb linkage NOT SUCK!
Aaron Cox
post Jan 18 2009, 07:15 PM
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Ok, I have tried lots of Carb Linkages over the years, and CB performance tends to be revered near the top end with regards to value and performance. There are a few other linkages out there that I like also...

So fast forward 5yrs, and the CB performance linkage has accrued some sucky slop from years of ball in hole wearing. Slop = bad, causing the carbs to not be synched during mid throttle....

Mind you this is the second or third crossbar replacement... even with grease, the hole gets ovaled and sloppy.

So, how do we fix this? How can we improve upon their design, BUT not go purchase ANOTHER linkage?

Well, simple my friends. A little machining, and parts selection and bobs your uncle!


Step 1, Purchase spare set of CB linkage base plates. Proceed to lop off the uprights near flush with the ridge for the air cleaner.
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Step 2: Bring beer to a buddy, and he will let you use his mill. Or will even mill things for you (IMG:style_emoticons/default/smile.gif)

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Step 3: Order a bunch of parts from mcmaster.com, Heim Joints, Shoulder Bolts, and Springs (IMG:style_emoticons/default/smile.gif)... Followed by - Find out that mcmaster carr will send you homo pinkish red heim joints and laugh at yourself.

Step 4: Drill and Tap Base plates for heim Joints

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Step 4: Measure 3x, and cut your new extra long cross bar to length, drill and tap ends to fit the shoulder bolts.

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Step 5: Install stainless springs, Stainless Shoulder bolts, and use blue loctite on all threads.


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Step 6: Install onto car, note what a great success it is, and drink copious amounts of beer to give yourself a pat on the back.

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The setup works great.
It gets rid of the big extension lever on the offset version of the CB plates.... Gets rid of the worn ball and socket pivot, And self centers like the original linkage did.

Hindsight, I would order bearings instead of heim joints next time, and possibly order slightly stiffer springs, or possibly add tension springs on the other side of the heims to increase centering ability.

Enjoy (IMG:style_emoticons/default/smile.gif)
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So.Cal.914
post Jan 18 2009, 07:32 PM
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(IMG:style_emoticons/default/smilie_pokal.gif)
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Aaron Cox
post Jan 18 2009, 07:33 PM
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Additional:

The goal was to mimic the TRIAD design, but improve on it also. Ideally, you use the centering spring technology used on CB's design, but improve upon it with heim joints like Triad uses.

A marriage of 2 good systems = a better system for less money.
245 for a linkage is too much.... The way i did it, can be made for ~ 60 bucks or so.


Triad Linkage
(IMG:http://www.triadwestperformance.com/Images/linkage-large.JPG)
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r_towle
post Jan 18 2009, 07:35 PM
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Nice job. I had a setup like that on a race car...it was an old school linkage...
The one thing to watch (at least on a hypo motor) was that the motor itself, therefore the position of the carbs, expands up to a half inch.

Rich
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KaptKaos
post Jan 18 2009, 07:40 PM
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Great thread! Who wrote it? :ducks:
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Aaron Cox
post Jan 18 2009, 07:40 PM
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QUOTE(r_towle @ Jan 18 2009, 05:35 PM) *

Nice job. I had a setup like that on a race car...it was an old school linkage...
The one thing to watch (at least on a hypo motor) was that the motor itself, therefore the position of the carbs, expands up to a half inch.

Rich


Good point-
Thats what the springs are there for. I designed upwards of 3/8" expansion into the bar. As the motor grows, the spring force lessens and the bar still stays centered (IMG:style_emoticons/default/smile.gif)
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r_towle
post Jan 18 2009, 07:56 PM
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Welcome back from your self imposed exodus.
Are you finally and Engineer?

Rich
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scotty b
post Jan 18 2009, 08:30 PM
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HIGH FIVE


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FourBlades
post Jan 18 2009, 08:56 PM
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Classic thread???? (IMG:style_emoticons/default/piratenanner.gif) (IMG:style_emoticons/default/smilie_pokal.gif) (IMG:style_emoticons/default/piratenanner.gif)

John
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Jake Raby
post Jan 18 2009, 09:05 PM
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Cool! One of the things on my task list has been to make a production unit "update kit" to do this with the CB linkage easily. It does make a world of difference.
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Aaron Cox
post Jan 18 2009, 10:25 PM
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All you need is a few poor college kids who like beer to machine kits for you (IMG:style_emoticons/default/laugh.gif) the hardest part of mass producing a kit would be the custom bar lengths....

Only took a few hours start to finish
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So.Cal.914
post Jan 18 2009, 10:56 PM
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I am going to make one. (IMG:style_emoticons/default/smile.gif) Very cool idea.
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craig downs
post Jan 18 2009, 11:14 PM
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Awesome
I miss your project threads, they are always fun to follow along. I hope you have more up your sleeve.
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'73-914kid
post Jan 18 2009, 11:31 PM
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Hmmm....I just bought a bought a complete CB set.
Brand new, and after daily driving use, how long is the linkage going to last?
This would be any easy thing for me to make, but I would like to find out how long it will be before I get the fitting ovalling out.

But first, I'll need to get my engine so, but everything actually seems pretty strong and tightly clearanced, so I'm not sure what I'll do..... (IMG:style_emoticons/default/unsure.gif)
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Aaron Cox
post Jan 19 2009, 01:02 AM
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QUOTE('73-914kid @ Jan 18 2009, 09:31 PM) *

Hmmm....I just bought a bought a complete CB set.
Brand new, and after daily driving use, how long is the linkage going to last?
This would be any easy thing for me to make, but I would like to find out how long it will be before I get the fitting ovalling out.

But first, I'll need to get my engine so, but everything actually seems pretty strong and tightly clearanced, so I'm not sure what I'll do..... (IMG:style_emoticons/default/unsure.gif)


You'll notice some slop after a year or more.....

You could always just replace the bar and balls when it happens....


BTW - why does CB performace REAM you on shipping? 12 bucks to ship a cross bar.... and they dont tell you what it costs up front.... (IMG:style_emoticons/default/blink.gif)
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PeeGreen 914
post Jan 19 2009, 01:07 AM
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Just when you think you're done...wait, there is more..lol
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Nice work Aaron (IMG:style_emoticons/default/beerchug.gif) It's always fun making things (IMG:style_emoticons/default/piratenanner.gif)
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ConeDodger
post Jan 19 2009, 01:10 AM
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Great thread but it looks like SirAndy took that second pic with his old camera! (IMG:style_emoticons/default/shades.gif)
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ottox914
post Jan 19 2009, 07:19 AM
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QUOTE(ConeDodger @ Jan 18 2009, 11:10 PM) *

Great thread but it looks like SirAndy took that second pic with his old camera! (IMG:style_emoticons/default/shades.gif)


Dd you read step 2 carefully- bring beer to a buddy. It doesn't mention who was to consume the beer. Shame to waste it on the photographer!
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biosurfer1
post Jan 19 2009, 11:33 AM
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QUOTE(Aaron Cox @ Jan 18 2009, 11:02 PM) *


BTW - why does CB performace REAM you on shipping? 12 bucks to ship a cross bar.... and they dont tell you what it costs up front.... (IMG:style_emoticons/default/blink.gif)


No kidding Aaron...I bought my fuel pump for them and they charged $35 shipping for a $50 pump. When I called to ask "WTF" she said they made a mistake and she would credit the difference back to me. My mistake was I didn't ask what the credit would be....it was $17 so shipping was still $18 for an item that would have EASILY fit in a $5 flat rate box from USPS.

I hate when companies do that!
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rhodyguy
post Jan 20 2009, 10:11 AM
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springs allowing for side loading suck. much like the stock cb. next time drill, tap and the bar ends using bolts with jam nuts to keep the bar where you want it when the engine is heated up. just like a triad. so...orginal linkage cost, make a throttle cable holder(we've been down this path), eventually have to endure a shitty carb snapping and poping engine, $60+ on improvements, beer, for those of us who are unable to impose upon a friend add what ever the market will bear for machining and you'll almost have a triad. mine is powder coated your's isn't. hi aaron.
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