Gear Shift Framework

[alias23]

Just looking over pictures of the gear shift naked and curious... 

It seems that stiffening the framework is one way of improving the shift. Alitech go major hog on a fully redesigned and super stiff cage. 

For a slightly less OTT option has anyone tried to just take the existing design and use thicker ali for the framework? So instead of the OEM (let's guess 3mm thickness) use 6mm... an idea?

[MartynB]

But that's not aluminium by my reckoning. Looks more like zinc passivated steel, which at 3mm should be pretty stiff. Do you actually see the frame flex? If so, I would have thought some judiciously placed cross braces would do more good than thickening.

Actually, looking at the parts diagram on Deroure, it looks like the frame is cross-braced, so I'd be surprised if there was appreciable flex in that. Are you sure it's not more about slop in the mechanism? 

[alias23]

I'm likely going to run the shifter naked for the next few track days to check flex... I guess the question has come from researching a few threads on improving the gear shift under load. 

The Alitech cage for example seems to have been designed specifically to stiffen the frame that support the shift.

Hence the thinking...

Sector111 have just realised an interesting design which is a little more OEM look friendly... 

[French Frie]

saw the Alitech stuff "in flesh" this week-end ... impressive, but very intrusive in the cockpit space ! can't talk about how efficient it is, though, as it wasn't connected to the box yet  ...

PS: note to Lotus Cars : please try to make the handbrake lever flush when released ... on the IPS especially, it feels really high and intrusive, and I often think it is not fully released and double check it ! maybe an electrical one would solve the problem  ?

[alias23]

21 hours ago, MartynB said:

Actually, looking at the parts diagram on Deroure, it looks like the frame is cross-braced, so I'd be surprised if there was appreciable flex in that. Are you sure it's not more about slop in the mechanism? 

Looks as though this chap has added further rigidity with an additional cross brace

26 minutes ago, French Frie said:

maybe an electrical one would solve the problem  ?

NOOOOO ????

[French Frie]

 it'd imply a new mandatory part in the tool box, which would fill the boot  : 

 

[MartynB]

23 hours ago, alias23 said:

I'm likely going to run the shifter naked for the next few track days to check flex... I guess the question has come from researching a few threads on improving the gear shift under load. 

It would be good if you could mount up a GoPro running a decent frame rate, pointing at the shifter frame. Maybe under the dash?

I'm interested to know what you find. My engineer's instinct suggests it won't be all that significant, but then I don't have the old version, so am going on my interpretation of the pics and diagrams. I could be way out.

[Hangar 111]

I don't think the frame itself usually flexes much, but fixing points (or lack of) to the chassis are more likely.  The rest of it is in the mech itself, usually the blue nylon bush.

Dave

[TBD]

That has often been quoted, but I believe the real issue is the ball joint for the crossgate and the cables themselves.  

[Julian73]

On 7/12/2017 at 05:51, TBD said:

That has often been quoted, but I believe the real issue is the ball joint for the crossgate and the cables themselves.  

VSA race team over here in US recommends replacing the ball joints with true heim joints to remove play from the rubber inserts