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Hi folks. I’ve been here for a few years but still consider myself a newbie next to you guys.
Anyway, I seem to fret all the time thinking about my accelerator cable breaking. I particularly have never liked the way the cable drags on the body and the fan shroud as it passes through .Has anyone attempted to fabricate a rod with ball caps instead of the cableI. I thought, unlike the 356 with a bell crank, maybe go straight through the fan as it exits now to the linkage. It seems that it may be a little more positive and I wouldn’t have to take Zanex all the time. What do you speedster brainiacs think. Thank you in advance.



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I think that in 8 years of driving I never broke a throttle cable and never worried about it, ever. I also think that @MusbJim, who has more miles than most, has never broke a throttle cable either but he can positively confirm that. So either make the complicated modifications or just carry an extra throttle cable as insurance and just go drive. Like all things Murphy, carry an extra throttle cable and you'll never need it.

@Robert M -  thanx for props, my brutha!

@Gotno356 - Tom, there should be a throttle cable tube that passes through the fan shroud...

Throttle tube

...through which the throttle cabe is inserted. The function of this tube is to prevent just what you described, "...the cable drags on the body and the fan shroud as it passes through".

Throttle tube2

The 'spring and cap' are normally used in stock throttle cable configuration. The spring/cap are not usually used in a dual-carb set-up (such as typically found in our Speedsters) because there are usually return springs incorporated into the carb throttle assembly.

Check that you do, in fact have the noted throttle cable tube, to alleviate your concerns with cable fray.

That being said, returning from one of our West Coast Cruises, I DID have a throttle cable break in the middle if nowhere ( IIRC - I had 95,000 miles on the Speedster at the time). I assessed the damage and scrounged around the shoulder of the freeway until I found a discarded shoelace. 'Necessity being the mother of invention' I MacGiver'd the following repair and continued the remaining 100 miles home without issue.


I hope you find this info useful.


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Last edited by MusbJim

I carry a spare throttle cable simply because I'm OCD (or CDO, depending on how you you look at it).

I've been involved with VW based dune buggies and now Speedsters since the 1960's.

I have never had a throttle cable break in all those years.

HOWEVER!  One of the members on here, @WildBill , had a throttle cable break at an event years ago and I stopped with him to help, while the rest of the group (30 other cars) continued on towards dinner.  IIRC, we had the cable replaced with my spare in about 15 minutes by feeding it through from the pedal end.  You don't even have to move the carpet out of the way.

If you carry a spare, the one being used will probably never break.

Last edited by Gordon Nichols

I had a throttle cable break near Christiansburg, Va one time in my speedster heading to Carlisle from Key West or it may have been the Cali to Carlisle trip. Very nicely, Jack Crosby donated his spare on the spot ( and wouldn't take a nickel for it ) and I think Lane Anderson did much of the re and re in the Hotel parking lot. Now I carry a spare throttle and clutch cable among other things.

I've often thought about running a length of piano wire from the carb linkage area through the tube Jim refers to right into the back seat area for emergency use. Hook the aft end to the carb linkage and a shoe lace to the front end and you got an emergency throttle in your hand or even further forward to your right foot I guess which would make shifting easier.

Last edited by David Stroud IM Roadster D


One thing to consider is that if the cable breaks, the carbs will always return to idle.

If a control rod passing through the shroud ever jammed, the throttle could get stuck open . I think that would have me worrying more than a cable breaking.

Also, if the cable breaks, it's likely to happen where it exits the shroud, near the hexbar, as that's where it rubs the side of the tube the most. But that area is easy to inspect for fraying. Some light lube (like Tri-Flow) at that spot probably isn't a bad idea, either.

Cleaning and lubing all of the 'wear points' in a hexbar linkage should be a part of routine maintenance, and inspecting the cable should be done then, too. Also, besides making an engine drift out of tune, friction in the linkage can wear out a cable sooner.

All of this nonsense must be why they invented the Sync-Link. I'll probably get a Sync-Link the day after my cable breaks.


Last edited by Sacto Mitch

The hexbar linkage can be permanently wear-proofed for 20-30 bucks and a few hours time. Heim joints, 5/16" ID. Invented by RS-60 Mark and myself back in 2006.

If your throttle jams, turn the key off and push the clutch in. Coast to the side of the road. There is no column lock on 99.9% of these cars to worry about.

I don't know who makes it, but there was a pulley and bracket thing that bolted to the fan shroud for the cable to ride in. It prevented wear that frayed the cable.

Also, x2 on the Heim joints. A nice upgrade to any hexbar linkage.  

I think I saw someone on the samba who had also designed something for CB specific hex linkages… let me look through my files.

here is what I found in my records… 1 & 2 require no modification of carb linkage top plates, and install in minutes.

1) for CB hex linkage:


2) for EMPI hex linkage:  . He used to sell the kit without the top-plates as well.  I think I just called him and he gave me a price- lower than listed on his site  ( without his custom top plates)


3) or you can modify your top plate with a heim joint as referenced by Danny. The kit I purchased was from Gordon Nichols ( awesome kit/solution), requires a little modification of your carb top-plate, but manageable project.

I actually tinkered with both the Heim joint mod (3) on an CB top plate, and the Bergman solution (2)  on a stock EMPI carb plate.       Last six years i have been rolling carefree with the Bergman solution without issues or unnecessary carb adjustments… Only because when I upgraded to Webber 40s ( from the EMpI 40s) I gave it a shot since I had a new EMPI hex bar in the garage and I wanted new shiny parts on the engine.

hope this helps.


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Last edited by Lfepardo

That little roller gizzie is the absolute bomb.  First I have heard of it.  Neat stuff.  Maybe a little overkill, but hey, its a hobby . . .

i have broken a throttle cable and replaced it by the side of the road with a spare in about 20 mins.  Mention of lithium grease from time to time is good advice.  They make a solid pin that fastens to the braided cable end that then is captured by the swivel on the hex bar arm.  This does lessen considerably the repeated over-flexure of the braided cable.  The cool little roller shown here is a much better idea.  I love it.

Heim joints on the hex bar pivots: clearly the right idea.  @Gordon Nichols has provided a little parts bag and instructions on how to do that for a nominal fee.  You do have to cut some metal and drill two holes, but it's aluminum and not too hard.  And is a world of difference. That sloppy std hex bar pivot thing is terrible.  IMHO.  Someone here could post a picture of how that works, I'm sure.

I think the all-time fastest throttle cable replacement I've seen was on an original Speedster and done by Porsche Mechanic extraordinaire, Rainer Cooney, at an event at Watkins Glen on the side of the road.  

He had a spare cable in his frunk, a pair of pliers with a wire cutter, a 2"-ish long piece of shrink tube that just fit over the cable OD, along with a tube of "Dyna-Lube" and a BIC cigarette lighter from his spares.  

He got in near the accelerator pedal, cut the end off of the throttle cable at the pedal with the wire cutter, slipped the shrink tube over the cable and then inserted the engine end of the spare cable into the other end of the shrink tube so they were about even and shrunk it with the lighter.

Then he told the car's owner to slowly pull the old cable through from the engine end and he lubed the new one as it was going in.  Slipped the pedal end into the hole of the pedal when he still had a big loop before the cable was fully pulled through (the pedal end is a "Z" bend) and then went back and attached it at the linkage end.

He was almost done in the time it took to read this post.  I was very impressed and when I got home I added a piece of shrink tube to my spare cable and threw a BIC lighter into my tool bag.  

Pretty slick, huh?  Just food for thought, Replica-istas.  

Never get caught on the side of the road by a frayed/snapped throttle cable!!

@LI-Rick posted:

@Lfepardo, I think it was Bruce Tweddle that originated the ball bearing upgrade for the linkage years ago. He still advertises it on TheSamba.

I really like that. I did the heim thing probably 15 years back. It was fine, but not as precise as the Sync-Link. It's the drop arm heims I always struggle with - the quality is pretty chippy, and they tend to want to seize or get sticky. I've never found good replacements, and I've looked.

Got an industrial supply source (besides CB, et al)? Grainger, McMaster/Carr, Zoro?

@Stan Galat posted:

I really like that. I did the heim thing probably 15 years back. It was fine, but not as precise as the Sync-Link. It's the drop arm heims I always struggle with - the quality is pretty chippy, and they tend to want to seize or get sticky. I've never found good replacements, and I've looked.

Got an industrial supply source (besides CB, et al)? Grainger, McMaster/Carr, Zoro?

Stan, I’ve used this place a bunch of times.


OK, full disclosure here.

As I've mentioned more than a few times, my engine's got about 40K miles now, after about nine years in the car. When it was built I was mostly concerned with crank, cam, cylinders, heads, carbs, (and cost) etc. — the major bits. I relied on the engine builder to install a decent linkage. My master mechanic set up the downlinks, set the angles, adjusted the lengths, and it's all run pretty smoove ever since.

These downlinks have never needed adjustment after the initial setup, don't drift out of 'true', the two sides are in nearly perfect synch, and all that is required for perfect harmony in my domain is an occasional cleaning of the idle jets, tweaking of the 'mixture' screws and an even less frequent idle stop adjustment. These 'adjustments' are usually a quarter turn or less. But again, the linkage itself never needs any tweaking.

Whenever discussions of heim joints come up, I've always assumed I don't have them and instead have whatever the low-priced alternative is that is standard nick on your basic hexbar linkage. Thing is, what I've got looks a lot like photos of gen-u-whine regulation heim joints.

So what exactly are these called, anyway?

And should I attribute my good fortune to clean living and kind thoughts towards my fellow man?


(Yes, I know, they're a bit shmutzy now and in need of some cleaning.)



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Last edited by Sacto Mitch

Those are the downlink heim joints. Every hex-bar setup has them. I'm glad yours are still limber. Shoot some grease in them now and again.

What theses fellows are talking about is the ends of the hex-bar. The stock setup is a ball end that is held in a hole in the hexbar itself, by means of a spring on either end. The stock setup is pretty sloppy. The heim joint conversion replaces this ball/spring/hole arrangement with a hardened shaft either threaded or epoxied in the hexbar hole, and a heim-join replacing the ball end. A picture, in this case, is worth 1000 words.

Gordon will probably provide both (pictures and 1000 words).


Here's what I've got there:


The gap next to the nylon washer also gets a shot of Tri-Flow and a wipe a few times a year. This keeps it moving freely.

The hex bar does have some freedom of movement, both left to right and axially, but would seem to need a little of both to keep from binding. If it's pushed off to one side, when the throttle cable is tensioned, it centers itself and doesn't drift around from that position.

So, this has always worked without a hitch for me, without introducing any synch problems. Maybe the key is just keeping it clean and lightly lubed?

Or paying really close attention to getting the downlinks truly vertical and the same on both sides? I can see how having them different would introduce different forces on each side and how that could make the two sides wear differently over time.



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Last edited by Sacto Mitch

The side to side motion is desirable, @Sacto Mitch - it's movement front to back and up and down (in the end joints) that introduces forces that pulls the lever arms out of sync with one another. The fact that you don't have it with an EMPI linkage (which is what you have) is amazing.

The fact that your down link heims move freely is an advantage that cannot be overstated. In the LH  picture above (not the most recent post, the one when you asked the original question), you can see that the bottom (carb side) heim is at the limit of its ability to articulate. Lots of times when that's a normal riding position, that heim (or any one so articulating in the joint) will wear, then stick and bind.

I've also had the threads on the down links (one LH, one RH) get rough and not adjust freely. You've never needed to adjust yours, which I find to be incredible, but if it ain't broke - I'd not fix it.

Whatever maintenance you are doing, keep doing it. It's clear that your dance with your car is paying dividends. I'm a ham-fisted ape, and I mash my loud pedal with a size 11 Red Wing boot - introducing a lot of wear on linkage. Your more genteel approach is obviously serving you well.

Last edited by Stan Galat


Maybe it's because I've always felt that every single part of this car will snap off or bend or crumble if held, twisted, or pushed too firmly that I handle the driving inputs the same way.

I never stomp on any of the pedals. I brake lightly, ease the clutch out and roll on the gas. I don't know why, but unlike any other car I've ever owned, I have this compulsion to be smooth in this car.

And this has started to affect how I drive my other cars, too.

I pay more attention to getting double-clutched downshifts just right, to dropping in without using the synchros at all.

It could be a Zen thing, but more likely I'm just becoming an old fart.


A drop (1 drop) of oil on each of the downlink heim joints twice a season does wonders for their longevity.  Same thing for the bar heim joints (if you have them) - clean them with a rag and then a drop of oil on both sides and you're done.

What @Sacto Mitch has:


And what some others have:


There is a spacer between the hex bar and the heim joint, inside of the spring, to keep everything centered.  inside of that spacer is a 5/16" OD metal dowel that's pushed into the end of the hex bar and then pinned with a roll pin.  The upright tab that holds Mitch's bar in place is removed and the upright, male-end heim joint added and adjusted for height.

Mitch - I can send the rework instructions to you, if you're interested.  Parts list and illustrations included.


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Smoothness* is the glue that keeps you stuck to the road, as we used to say in HPDE motorcycle school.  A wonky throttle linkage will make smoothness a more difficult aspiration to achieve.

*Being smooth does not preclude being agressive or fast with your inputs. In the proper setting very fast inputs may be required to be smooth. An old friend of mine raced in the SVRA and was voted smoothest driver multiple times. He did that in a Dekon Monza, and absolute stone axe of a car. You would not believe how fast his hands and feet were moving, while outside the car it looked so fluid arching around the turns. He wore size 11 Red Wings, too.

Yeah, Michael - I repeat it to myself every time I'm hooning, "eyes up, smooth inputs". But we are who we are, and ingrained personality traits die hard, even when you'd like them to just take a break. And so, I still sometimes find myself absolutely matting the throttle like I'm trying to push it through the floorboards.

That puts a LOT of strain on things.

Last edited by Stan Galat

true story:  Eons ago, (ok, several decades ago, when we kids were jamming to U2, R.E.M., Poison, Bon Jovi, Paula Abdul and 'music still on MTV') I'm driving my '74 beetle home from work and said loud pedal falls to the floor under my foot, simultaneously, the engine falls to idle.  I got nothing, like running out of gas but engine is still idling....   crap, now what?   I coast into the fire station parking lot, and open the engine lid.  Work the throttle linkage on the carb and vroom, vroom.  Then see the broken end of the cable sticking out of the fan housing and the swaged end of the cable still nicely secured in the throttle linkage.  Double crap...   no tools, no spares..  knock on the fire station door, 'Hey guys you got any tools?'  guy comes out with a hand held tool box that looks more like fence repair..   hmm screwdriver, hammer, linesman pliers... yeah that's about it.  So what can I do to fix this?

I happen to have a coat hanger in the car from uniform shirt. (working as tire changer for the summer)  So I cut a section of hangar wire, formed a loop hook at one end, inserted throttle cable through the loop and twisted the wire back on itself and used a bread tie to tie the cable from unraveling.  Then removed the throttle cable swaged stick from the carb linkage and secure the other end of the hangar wire into the carb linkage.  Started the car... now vroom, vroom from the loud pedal.  Job done.  Then I drove home to really fix it.  Alas, I had to drive it like that for a week until the cable came in.  (as  the cable was not in stock).    Then I pretty much did the above method of heat shrink, only with electrical tape, to install the new cable.  I learned a lot about wrenching on type 1s that summer.. re-learning stuff now as I'm trying to lose to @WOLFGANG for longest build.    

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