Throttle cable return

[RafM]

72 Twin Cam

Having more or less finished restoring my TC I'm in process of ironing out the more minor details.

The car has Dellorto carbs and I've been working on tuning them correctly. I can highly recommend 'How to Build & Power Tune weber & Dellorto carbs'
by Des Hammill, it's a very comprehensive guide.

The throttle cable is routed from beneath, it pulls the throttle arm lever down and works smoothly. I have fitted the standard return spring, but it feels too strong
making the pedal quite stiff and heavy. Maybe it's the wrong one, I heard that the Weber spring is stronger?

Regardless of that, does anyone know of an adjustable return spring/bracket set-up that will fit on top of the carbs? I want to stick with a single cable system.

Thanks, Raf.

[jbcollier]

https://www.dellorto.co.uk/shop/car-accessories/linkage-kits-accessories/link08-dhla-single-cable-linkage-kit-fully-adjustable/

http://rdent.com  (click on carb - linkage - and scroll down)

Many others I'm sure.

[BDA]

She’s a beauty, RafM! Good job! 

[EuropaTC]

The throttle cable is routed from beneath, it pulls the throttle arm lever down and works smoothly. I have fitted the standard return spring, but it feels too strong
making the pedal quite stiff and heavy. Maybe it's the wrong one, I heard that the Weber spring is stronger?

Yep, the Weber spring is noticeably heavier in operation and it's thicker wire as well. Without going to look, I'm not sure the older Weber spring fitted to my Elan would go on the Dellorto linkage, it's quite a bit thicker.

The pedal won't be as light as a modern car but it shouldn't feel heavy. The inner wire should move freely with finger pressure when disconnected at the carb end, if not then I'd look for sharp bends in the cable or maybe fouling at the passenger footwell where the carpet covers the end of the pedal assembly.

Brian

[RafM]

https://www.dellorto.co.uk/shop/car-accessories/linkage-kits-accessories/link08-dhla-single-cable-linkage-kit-fully-adjustable/

http://rdent.com  (click on carb - linkage - and scroll down)

Many others I'm sure.

That's exactly the kind of thing I was looking for JB.

From some of the replies it looks as if the Weber spring has been fitted in error and is too strong.
The original spring is simple and obviously works but I like the idea of having some adjustment options.

It's nice to be fine tuning rather than looking at huge jobs now.

[EuropaTC]

These shots are from the SJS website but show the differences between the weber & dellorto springs. The dellorto is at the top, weber at the bottom and even if you can't tell the wire thickness without direct comparison, the curled ends are different with the weber being "flatter".

[RafM]

These shots are from the SJS website but show the differences between the weber & dellorto springs. The dellorto is at the top, weber at the bottom and even if you can't tell the wire thickness without direct comparison, the curled ends are different with the weber being "flatter".

I ordered a Dellorto spring but looks as if a Weber one was sent instead...

[EuropaTC]

I ordered a Dellorto spring but looks as if a Weber one was sent instead...

In that case you'll be pleased at how much faster the car goes with the lighter spring