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Gearchange Issues dissected

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What he said, thanks for sharing Thomas and I'm pleased these problems are hopefully behind you now :)

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Just had my cables adjusted as per #3 by B&C under warranty (MY11 S and they reckon the cables were as good as any they have seen). Has made a massive difference to changes from 1st to 2nd to 3rd - much smoother now. To be seen whether I will have to keep adjusting them over time as the cables stretch and the mechanism wears, but at least the solution is relatively simple. The M100 used to have problems with the gear cables as well - the ends used to break off!

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Thomas, you have my vote for the tech post of the year to date. Even though I've suffered none of those issues ........yet. (13K miles since June 2010.)

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I'm going to amend this thread regarding a further issue that may be common to the Evora and that we are currently analyzing on my car.

Issue #4: Synchronization (unconfirmed): Gearchanges are balky, gear engagement is seemingly blocked, causing very long shift times. Issue is prevalent specifically above 3500 / 4000 rpm, more pronounced on downshifts than upshifts. Specifically between gears 6,5 and 4 (affected gears may vary).

Now that all the "simpler" issues above have been resolved in my Evora the true nature of the key problem is becoming more evident. Whilst synchronization sometimes works quite acceptably (specifically when the car is cold), downshifts following a longer high speed run are nearly impossible and in no way worthy of a sports car. From various posts here and on LT it seems that several owners have a similar issue, whereas others reply that they have no problems.

Status/resolution: Our design analysis to date has shown no potential for adjustment, fitting or alignment that would affect the synchronization, leaving only a gearbox internal issue as potential cause. We have asked a Lotus Engineer to inspect the car on next opportunity in order to clarify whether this is a bug or a feature.

Clearly the Evora gearbox from Aisin was originally designed for use in a Diesel powered car, i.e. not specifically designed for the high rpm's reached in the Evora. Don't you wish their choice had fallen for a ZF-gearbox, or a dual-clutch unit?

I'll keep you posted....

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I'm going to amend this thread regarding a further issue that may be common to the Evora and that we are currently analyzing on my car.

Issue #4: Synchronization (unconfirmed): Gearchanges are balky, gear engagement is seemingly blocked, causing very long shift times. Issue is prevalent specifically above 3500 / 4000 rpm, more pronounced on downshifts than upshifts. Specifically between gears 6,5 and 4 (affected gears may vary).

Now that all the "simpler" issues above have been resolved in my Evora the true nature of the key problem is becoming more evident. Whilst synchronization sometimes works quite acceptably (specifically when the car is cold), downshifts following a longer high speed run are nearly impossible and in no way worthy of a sports car. From various posts here and on LT it seems that several owners have a similar issue, whereas others reply that they have no problems.

Just to give an update on this:

Status/resolution: We finally concluded together with Lotus Service Engineering that changing the transmission oil would be sensible task to takte prior to removing and exchanging the gearbox. Surprisingly the oil change improved the situation considerably, to a point where gear changes are on par to other Lotus Evora. I have now covered 250 kilometers since, covering from stop-and-go through 250 Kph and gearchanges remaine reasonable throughout.

Though we didn't see an contamination our assumption is that some dirt was hampering movement of the synchromesh. We did replace the original fluid with highest grade synthetic oil.

I'll be going on vacation with the car next week, and will gladly report developments after 3000 kilometers following my return.

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Which was the oil you used, Brand and grade? I did think about a change for my car that is a little baulky going up through the box when pressing on.

Trevor.

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Which was the oil you used, Brand and grade? I did think about a change for my car that is a little baulky going up through the box when pressing on.

Trevor.

Castrol Manual TAF - X SAE 75 W 90 / API - GL 4

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That's what the Esprit uses and Castrol are stopping making it!

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It was never noisy, just didn't change gears well.

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I would be tempted to try my favourite Redline MT90. When talking to the factory staff about it in reference to the Esprit they regarded it as good oil.

Trevor.

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That's interesting - I had a similar issue on my Elise SC with a baulky 2nd/3rd up/down shift which was cured by replacing the gearbox fluid with a motorsport-rated version.

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If you've been following my threads you know I've had issues with changing gears on my Evora for almost a year. We've changed the shift cables twice and even changed the transmission oil, all without enduring improvement.

Well, things continuously degraded during our vacation, a 3.000 KM trip to Southern France. Gear changes became increasingly difficult. In fact, sometimes the only way to get into reverse was to stop the engine. At least this had the advantage of making a sporadic problem reproducable.

So, today the car went to the shop. I had also noticed in the last few days, that the car would start creeping once I put 1st gear in, despite having fully depressed the clutch. Kind of like an automatic transmission when you release the brakes.

Well, it now looks like the clutch isn't releasing fully, despite full movement of the pedal and clutch lever. At least this is the conclusion reached wih the Lotus service engineer and would explain why gearchanges are difficult and synchronization doesn't work.

Looks like its going to be a big job, as I'm told replacing the clutch on this car means disassembling the complete clam and removing the engine.

Lets hope this is the true cause and I can finally enjoy the near perfect Evora in its totality! I'll keep you updated.

Oh, and if anyone else has had a similar problem I''d be glad to get more feedback. :gathering:

Edited by TBD

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I really hope you get that issue sorted once and for all.

Good luck

Buddsy

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Yes, the car is with Timmy at West Side Cars.

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Watching this thread with interest. Am aware of a few owners who have been told "it's just the cables" or "they all do that" but are concerned about it possibly being clutch-related. Dealers and factory understandably reluctant to go down that route initially given the major work (30+ hours) to get the clutch off for inspection.

Hope you get it sorted and look forward to hearing what they find.

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Yeh.... I have...

I :animier: P :robo: S :animier:

ps At least the manual gearbox owners won't' have software issues! :comp:

Edited by Stirling_Villeneuve

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The clutch and transmission were exchanged yesterday. We weren't able to see what the actual root cause was, so its good that everything is simply being exchanged. I was hoping to get the car back on Friday, but now it looks more like next Tuesday. The recall for that oil pipe came through, so it makes sense to take care of that at the same time.

I'm really missing my car! :cry:

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Thomas, is that still a warranty issue?

Yes!

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I finally got my car back last Wednesday after my dealer exchanged both the clutch and the gearbox. It was a major job taht took 5 weeks, including waiting for the clutch plate on back order. I also had the MY12 steering wheel installed while the car was there.

This week I had the chance to do some travels and can report that the effort was worth it. Finally I can change gears without hassle or other troubles. Must have shaved at least a second off my 0-100 kph time. :thumbsup: :thumbsup: :thumbsup:

We weren't actually able to identify what was wrong with the old setup. We did notice some wear on the main shaft of the gearbbox, which was also unexpectedly sticky (as if covered by some gum). Clutch plate seemed fine though, but with a slight hot spotting on the pressure plate.

Notice the beautiful De Tomaso Pantera in the first photo.

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post-12365-0-35137400-1352365416.jpg

post-12365-0-00516400-1352365426.jpg

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Issue #4:I and one other owner I have spoken to had a problem with pulling away and gear changing. What happened was that when you released the clutch pedal and just as you add power as the clutch bites, the engine cut out causeing a kangaroo effect. The effecct was more fierce in 1st and second.

Resolution: The Clutch pedal has a position sensor mounted in it which had developed a fault. The sensor is used for the cruise control and also to protect the engine if you do something daft. Position sensor replaced and all is now well.

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