Photos or schematic of Twin 1 1/4 SU throttle linkages

[rolesyboy]

I have a complete set of twin SU carbs which arrived in a box. They look to be complete but I have no schematics to reference for assembling the various throttle linkages. I only have H4's which are entirely different. Does anybody happen to have any close up shots of these carbs to show the arrangement for these parts. Thanks. Mark

[InimiaD]

This might help in some way.

http://mk1-performance-conversions.co.uk/hs_tuning.pdf

[timmy201]

That's really helpful, I've been looking for the same info.

On a semi related note, most sets I've seen have all three return springs attached to the heat shield, but a couple have one spring connected to the airbox. Was this the way they were done originally?

[Spider]

On Coopers and Cooper S's (and Aust GTs), all 3 springs went back to the heatshield.

[LarryLebel]

Most Cooper/Cooper S twin carb air filter housings I have seen have a tab on the front for a return spring. If all the springs should be attached to the heat shield why would there be a tab on the air box for a spring? The Cooper S I had for 35 years had the third spring attached to the airbox. I don't know if it came from the factory this way. Regardless, what I liked about the setup was the spring acted on the throttle lever to pull it closed especially in the case the throttle cable was dragging.

[smithyrc30]

Maybe the three springs on the heat shield 'bar' comes from the original Cooper 997 which had no air 'box' just two pancake filters so there was no box to attach the spring to.

While some of the the throttle links I have seen/owned that fit between the carbs have a fitting to enable a spring to work when attached to the air filter box, it certainly is not all of them.

I prefer the attach to the bar method because it means you can easily remove the air box without messing about with the spring.

Certainly all the Cooper cars I have owned (and the MG 1100 and 1300 I had) all had the springs attached to the heat shield bar.

[smithyrc30]

Just looking at this listing on the picture of the engine reveals why the spring is on the bar, certainly when the crankcase vents were added to the carburetor bodies.

On the later setup it would not be possible to get the spring past the crankcase ventilation tubes.

http://www.ebay.co.uk/itm/MINI-INNOCENT ... 2ee43a1616

[Ronnie]

The Mk3 S has the spring on the air box as well as the Y piece! The spring is to maintain the clearance on the fork and peg linkage.

[Spider]

The Mk3 S has the spring on the air box as well as the Y piece! The spring is to maintain the clearance on the fork and peg linkage.

Got a photo or something? Not seen that set up before.

[Ronnie]

The Mk3 S has the spring on the air box as well as the Y piece! The spring is to maintain the clearance on the fork and peg linkage.

Got a photo or something? Not seen that set up before.

Mk3 S handbook I believe all the filter housings had an anchor tag on

[Spider]

The Mk3 S has the spring on the air box as well as the Y piece! The spring is to maintain the clearance on the fork and peg linkage.

Got a photo or something? Not seen that set up before.

Mk3 S handbook I believe all the filter housings had an anchor tag on

Cheers