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

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Step 3: Order a bunch of parts from mcmaster.com, Heim Joints, Shoulder Bolts, and Springs ... 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

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

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

Great thread! Who wrote it? :ducks:

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

Welcome back from your self imposed exodus.
Are you finally and Engineer?

Rich

HIGH FIVE

Classic thread????

John

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.

All you need is a few poor college kids who like beer to machine kits for you the hardest part of mass producing a kit would be the custom bar lengths....

Only took a few hours start to finish

I am going to make one. Very cool idea.

Awesome
I miss your project threads, they are always fun to follow along. I hope you have more up your sleeve.

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.....

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....

Nice work Aaron It's always fun making things

Great thread but it looks like SirAndy took that second pic with his old camera!

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!

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!

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.

I like the triad for one main reason that I can see right off the bat...see how the link arm is almost straight 90 degrees to the carb throttle shaft. That gives you no side loading on the carb throttle shaft.
What I don't like is it looks a bit flimsy.

Yours looks good Aaron, but the 90 degrees to the throttle shaft is very important to making it smooth and to stop premature wear of the shaft bearings.

Nice project Aaron. Looks like something even I could do. Hey! shouldn't you be looking for a job?

flimsy? Didn't apear to be when I had one. Very solid actually.

Aaron's system looks very nice and cost effective

I said "looks" I can't tell the metal thickness from the pic.
Why I'd be saying that is it does look a lot like the el-cheapo Type 1 linkage at first glance.

Mark,

Are you suggesting that the drop links should be vertical or as colinear as possible with the carb shafts? The position can be adjusted very easy. (they have allen set screws to set the distance from the carb)

I might be min-interpreting what you are asking about.

Kevin,
So you deal with play (up to a half inch) when the motor isnt fully warmed up or super warm?
Swapping out springs would be easy.... but I like to account for the play, versus letting it flop around until warm.

Aaron whats the McMaster part number for the heim joint you used?
Thanks,

Good work Aaron!!

The Bugpack bell crank works better than the CB cross bar. You have to modify it to remove the slop, but it is a better choice. I have had both and now I only use the Bugpack bell crank setup.

Looks like you did a good job with your mods. I hope it will work right longer than the original design.

Yes, the droplinks should not push in/out on the end of the throttle shaft.
Think of setting the endplay on a crank, you don't want it push/pulling it in that way as it causes wear.

This is one of the reasons I also like the bellcrank type, BTW I make my own.

Ahh, The arms are too long is what you are saying... so it is putting a load in the direction of the shaft. Got it...

Look at the triad again, As it goes through the travel, it will put a side load on the shaft also.....

Is it 2009 and... did Aaron Cox just post a fuching "How-To" article???

Watch for the flaming, flying, flesh eating sculls!!! Armageddon is upon us!!

Way-ta-go smartboy.

Ayup... The end is nigh!

See what else i can modify for fun... LOL

Bugpac has several linkage products. Which one are you refering to? I also have a 2.0 with dual Webbers and am looking for a better allignment or linkage system.