Author Topic: S2 Gear linkage upgrades?  (Read 391 times)

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Offline Richard48Y

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S2 Gear linkage upgrades?
« on: Tuesday,September 24, 2024, 11:29:29 PM »
I really did do several searches but was surprised to find no threads on upgrading the S2 shift linkage.

I am about to replace all the rod ends, and whatever the other two links are called.
The ones with a fragile ball-stud captured by a screw with a concave head.
Thinking they MIGHT be able to be replaced with a stronger studded rod end?

I will have to look at the other S2 here in the morning to see if there is space enough.
With the decades since the original builds I have some hope for clues on improvement.

Offline GavinT

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Re: S2 Gear linkage upgrades?
« Reply #1 on: Tuesday,September 24, 2024, 11:41:47 PM »
I replaced those well worn 'throttle linkages' with normal 5/16" rod ends but they do come close to hitting the chassis when traversing cross-gate.
I've thought 1/4" rod ends might be better in terms of clearance but haven't tried them.
The studded ones could also fit the bill, methinks and they are usually rubber sealed.

Offline Bryan Boyle

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  • 1974 Europa JPS #142 3291R
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Re: S2 Gear linkage upgrades?
« Reply #2 on: Thursday,September 26, 2024, 06:02:22 AM »
I really did do several searches but was surprised to find no threads on upgrading the S2 shift linkage.

Unless you're into serious reengineering, there is not much, on the 336 boxes in the S1/2s that can be done.  They ALL were a weak point.  That being said, when set up properly with fresh joints, they are useable, but will never be as nice as the snick-snick Elan box. 

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I am about to replace all the rod ends, and whatever the other two links are called.

1. Upgrade the in-cockpit joint at the top of the chassis with the TC arrangement.  RD has the parts, as I'm sure Bean et all do too.  If you can find a pair, replace the top hats at the bottom of the shift lever with sintered bronze bushings (polish the tang at the bottom...it couldn't hurt) and assemble with lots of grease.  You'll thank me later.
2. New heim joints for the bottom of the transverse mechanism at the front of the engine.
3. New rod ends for the top transverse link.  You may want to go up one size, but the standard parts work just fine.
4. New heim for the locator link on top of the tranny.  New rubber bushings tranny end of the link. 
5. New heim for the shift adapter at the back.
6. DO NOT forget the spacer under the rear heim or you will bind the joint when you move it.

Set up to spec as per the manual.  Distances across the transverse mechanism.  Length of the locator link at the top of the tranny.

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The ones with a fragile ball-stud captured by a screw with a concave head.
Thinking they MIGHT be able to be replaced with a stronger studded rod end?

Go up one size if you want, but make sure the center to center distances are the same.

Quote
I will have to look at the other S2 here in the morning to see if there is space enough.
With the decades since the original builds I have some hope for clues on improvement.

Most often "improvements" were the end result of redneck engineering to do enough to get it to work without understanding why/how it was designed the way it was in the first place.  Not saying the guys who assembled it on the line were engineers, but the folks at the drafting boards were pretty smart and came up with some interesting arrangements that, all things considered, did work.  Maybe not the best, but, the whole Europa is a compromised beast.  Maybe we have a different view 50+ years post-production.  Heck, we're further from the year it was designed than the year it was designed was from the Wright's first flight...think on that...
Bryan Boyle
Morrisville PA
Commercial Pilot/CFII/FAA Safety Team
Amateur Extra Class Operator & FCC Volunteer Examiner
Currently working on 3291R, ex 444R, 693R, 65/2163, 004R, 65/2678
http://www.lotuseuropa.us for mirror of lotus-europa.com manual site.