Twin Mikuni Solex K Motor

[GJM85]

I plan on running a set of R series 40mm Mikuni Solex sidedrafts, from an 18RG, on the 5k. I just had them rejetted and a few missing parts replaced. Using redline manifold, soft mounts and studs. The studs are about 10mm short which seems unusual considering....

 

There is a designated left and right hand carby with a common tongue type linkage and a ball and socket throttle cable connection between them. Originally being mounted on the left side of the 18RG, the same way a T series engine with T series Solex's is set up the throttle rotation is reversed when mounted on the right.

 

The first issue is the tongued linkage prevents the carbys coming close enough together to fit on the K series manifold, so it must be modified to close the gap. There is a 10-15mm width issue.

The second issue is the reversed throttle rotation. The linkage needs to be pulled clockwise from the left to open the butterflies.

 

Has anyone ran this setup, seen how it is done or has the know how? Just after some pointers.

Edited February 4, 2011 by GJM85

[Mick E]

not sure on problem being too close together, but check margard throttle cables on internet might give you an idea on linkages

cheers mick

[corollaart]

You may have set them up with out the carb linkage ,set up with linkage per carb then join together.Like weber ,dellorto type.

 

Make sure the venturis are tight ,bad habit of coming loose and burning the car to ground.

 

rob

[GJM85]

The tongued linkage

 

The ball and socket cable attacchment

 

To wide for the manifold

Edited February 6, 2011 by GJM85

[GJM85]

I have been thinking about halving the manifold. A $300 manifold. Modifying the tongued linkage to get them closer, then running a k series carburettor linkage off the carby closest to the firewall... not sure yet.

Edited February 6, 2011 by GJM85

[snot35]

In the past I have had to shorten shafts slightly on Webers to get them close enough together.

 

I'm thinking this same problem through at the moment with some Dellorto's that are currently on their way to me in the post :). I remember recently seeing someone who modded their original Aisin throttle wheel and used that. There was also a tongue that they managed to bend in the right direction so that balancing could be achieved. From what you've posted though, you've got your work cut out! You'll have some additional space, because I'm assuming you're not going to bolt them up without any insulators. It's a little unorthodox, but maybe you could mod and bolt up a stock throttle wheel and have the cable going down between the runners and behind the joining bridge? It's going to be fiddly, but it's the only way I can think of it all fitting.

 

I don't see how you're going to get the current arms on there to work though, without adding a lot of spacers. That's going to make the filter end very tricky in a '20.

 

Edit: If you're going to halve the manifold then you could keep the push rod and ball setup? I'd be a little cautious about how much the carbs will stay in sync if you're twisting the whole lot from one end.

Edited February 7, 2011 by snot35

[philbey]

I struggle to see how halving the manifold will fix anything, you can't just push them farther apart the distance between the two halves is set by the ports/boltholes.

[snot35]

Well he'll get the clearance required to swing the arm with the ball on the end.

 

Thinking about this more (and not about work :) ) I wouldn't halve the manifold, as then you'll only have two bolts holding on a reasonable amount of weight a fair way from where it is attached, on a thing that gets hot and vibrates! Sounds like a good recipe for all sorts of problems.

 

Another option might be to run the redline style arms but put the throttle plate arms at both ends of each carb and drive them from an upper shaft.

 

Either way, I don't think you're going to be able to use the stock linkages.

Edited February 7, 2011 by snot35

[jono1986]

Just a question to add to this does the redline manifold cover 40mm solex, webers and Dellorto's or is there a different manifold for each one?

[corolla_bitten]

yeah ive got solex's on a redline manifold, they are all the same pattern, on mine i had to file a chunk out of the manifold for the link, but my linkages are 180 degrees to yours, with the tounge and groove closer to the manifold, and the ball joint closer to the filters, may be as simple qas swapping them over.

[GJM85]

I struggle to see how halving the manifold will fix anything, you can't just push them farther apart the distance between the two halves is set by the ports/boltholes.

If I did choose to go and hack up the manifold it would only be to allow the linkage to pass between the runners.

 

 

Thinking about this more (and not about work :) ) I wouldn't halve the manifold, as then you'll only have two bolts holding on a reasonable amount of weight a fair way from where it is attached, on a thing that gets hot and vibrates! Sounds like a good recipe for all sorts of problems.

 

Another option might be to run the redline style arms but put the throttle plate arms at both ends of each carb and drive them from an upper shaft.

 

Either way, I don't think you're going to be able to use the stock linkages.

 

I'm not interested in causing problems for myself. The the redline linkage kit would probably be the best starting point for a modified set up, though i'm looking at all avenues to minimize work.

 

yeah ive got solex's on a redline manifold, they are all the same pattern, on mine i had to file a chunk out of the manifold for the link, but my linkages are 180 degrees to yours, with the tounge and groove closer to the manifold, and the ball joint closer to the filters, may be as simple qas swapping them over.

 

Rotating the whole central linkage setup 180 degrees is something I never considered. It should work because the carbys do appear to be symmetrical. Still doesn't fix the spacing issue or the throttle rotation problem.

[snot35]

I'd say for the most bolt on setup would be the redline kit and throttle wheels at either end. From there you're probably going to have to fabricate stuff.

[altezzaclub]

It doesn't look hard to drill & tap the left-hand part of the tongued linkage and move the bolts further towards the LH carb in your top photo. Then you can grind the ends off and move them closer.

 

A top mount shaft isn't too difficult, that's what I made for the SUs. The upright arms were fabricated from some rubbish metal I had lying around, the shaft was a cut-off long bolt and the quadrant was a stock one welded on. A Redline adjustable link goes down to the ball joint between the SUs.

 

It looks like you should cut the ball off and weld it on the other end, or can you drill and mount a ball between the throttle shaft and the tongued link?? That would put the ball linkage away from the manifold. Its all just levers and can drive you insane trying to work out how to get full throttle and idle!

 

here's what I ended up with-

[Chillin]

Please keep us updated, i have the same problem!

[GJM85]

Mr brother and dad decided to go ahead and figure out an arrangement for the solxe's. And f@$k me it worked the treat. I got pictures but my phone is dead so they'll have to wait for tomorrow. Shorted the tongued linkage 7.5mm on both sides. Retapped the folded side to allow the original pin screw to fix the tongue. Solid. Proccededto weld, file and fit an original k motor cable linkage to the carb closest to the firewall. The whole lot rotates to the full extent of the law. Top work!