| Home  Blogs Help Search Login Register  
« previous next »
Pages: [1] 2 3 4 Print
Author Topic: Modifying gear shift  (Read 25251 times)
hru
Sr. Member
****
Posts: 171


Murena Lover :-)


« on: December 03, 2005, 07:33:19 pm »

Hi Everybody

The original gear shift is a very poor construction, with lots of sloop & slack.
Has anybody tried to modify this ? - eg. maybe use cables from the steering of a speedboat ?


Best Regards
Henrik
Logged

Matra Murena 2.2
Will Falconer
Sr. Member
****
Posts: 161


« Reply #1 on: December 05, 2005, 06:06:48 pm »

The original isn't bad if all the worn components are changed.  I've driven low mileage 2.2's which have really slick changes but it's quite easy to get older cars up to near that quality.

While the original sockets had nylon liners we find that  solid steel ones are better and you can change the gearbox relay bushes from nylon to brass.

The worst part of the system is the top hat washer under the gearlever. but it's a cheap item and easy to change to get rid of lateral slop.

If you email off-list I can supply all the parts to bring it up to spec.
Logged
Matra_Hans
YaBB God
*****
Posts: 642


Owner of Bagheera, Rancho, Murena & Espace


« Reply #2 on: December 06, 2005, 07:22:45 am »

Hi
Most of the ball joints you can get from the local Valmet tractor dealer (or any other tractor workshop) if you are living in rural areas. This ball joints does not have any nylon bushes.

The tube under the car is flexing quit a lot side wards. I have made a support of this longitudinal gear tube, just in front of the engine. This has improved my gearshift tremendously. The support is mounted on the cross member between the fixation for the rearweel suspension. The mounting can be done without any drilling to or modification of the car.

Regards Hans
Logged
Anders Dinsen
Administrator
YaBB God
*****
Posts: 2822



WWW
« Reply #3 on: December 06, 2005, 10:38:58 pm »

Does anyone have a good description/explanation/drawing of the mechanism?

Ok, I helped myself. First, take a look at this picture of the inside of the gearbox:



Picture is from http://www.atspeedimages.com/1988_citroen_cx/clutch_and_gearbox/

Note the dark grey forks (where the red arrow points) that move the syncros (shown with the yellow arrows). There's one fork for 1-2, one for 3-4, and one for 5-R (5'th gear is obviously not fitted on the picture here).

This drawing is in the workshop manual:



G is the one that operates the stuff inside the gearbox.

The long rod B rotates and shifts from side to side as the gear lever is moved from side to side. These two actions will work slightly against each other, but it is the rotation that lifts G up to select the appropriate fork inside the gearbox.

People with experience tells me that the system can be restored to near-new-standard. I'd recommend replacing joints and checking the pivot points.
« Last Edit: March 10, 2006, 11:58:21 am by dinsen » Logged

'82 Murena 2.2 prep 142
'01 Grand Espace 24v
'08 Smart Fortwo 0,8 cdi
Anders Dinsen
Administrator
YaBB God
*****
Posts: 2822



WWW
« Reply #4 on: December 06, 2005, 10:43:37 pm »

The tube under the car is flexing quit a lot side wards. I have made a support of this longitudinal gear tube, just in front of the engine. This has improved my gearshift tremendously. The support is mounted on the cross member between the fixation for the rearweel suspension. The mounting can be done without any drilling to or modification of the car.

Hans, I don't quite get that. The tube is supposed to move sidewards.

- Anders
Logged

'82 Murena 2.2 prep 142
'01 Grand Espace 24v
'08 Smart Fortwo 0,8 cdi
Lennart Sorth
Administrator
YaBB God
*****
Posts: 817



WWW
« Reply #5 on: December 07, 2005, 10:06:16 pm »

[Hans, I don't quite get that. The tube is supposed to move sidewards.

which is true, but I guess the sloppyness can be so dominating, that fixing ANY part og the linkage can produce useable results. I know that more cars have Hans's solution fitted. (I think it was proposed by our own Stig .. well not THE Stig, but close)

However, personally I'll still recommend replacing all the worn parts. Specifically around the gearlever, and the other ball-joints.

On my 1.6 the knuckle-rods in front of the gearbox (connecting the L-shaped lever on the longitudinal rod with the gearbox) were the main reason. The ball-joint at the back of the longitudinal rod is also known to deliver quite some slack.

(Since then I had the engine converted to the XU9JA, which incidently gave me a brilliant gear-linkage, courtesey of  MatraMagic, but thats another story)

/Lennart
« Last Edit: December 07, 2005, 10:07:02 pm by Lennart » Logged

Lennart.Sorth@matrasport.dk
Murena 1983 1.9i silver // Alfa Romeo Giulietta 2.0d 2012 white // Smart 4two cdi 2010 blue //
Anders Dinsen
Administrator
YaBB God
*****
Posts: 2822



WWW
« Reply #6 on: December 07, 2005, 11:15:43 pm »

[Hans, I don't quite get that. The tube is supposed to move sidewards.

which is true, but I guess the sloppyness can be so dominating, that fixing ANY part og the linkage can produce useable results. I know that more cars have Hans's solution fitted. (I think it was proposed by our own Stig .. well not THE Stig, but close)

So where is it fixed, and how?

If the long rod can rotate around it's own axis, then the rotation will have the opposite effect as the sidewards movement, thus making it far less precise.

Pictures?? :-)
« Last Edit: December 08, 2005, 09:11:14 am by dinsen » Logged

'82 Murena 2.2 prep 142
'01 Grand Espace 24v
'08 Smart Fortwo 0,8 cdi
Lennart Sorth
Administrator
YaBB God
*****
Posts: 817



WWW
« Reply #7 on: December 08, 2005, 11:34:30 pm »

.. the opposite effect as the sidewards movement, thus making it far less precise.


Well, what you use from the movement is the rotation around the longitudinal axis, en the forward/backward movement, so even if the system was designed to move sideways as well, it is not really mandatory for the gearchange (at least on a 1.6, which I know the best)

It was a little triangular thing, with a bearing holding the rod steady, while still letting it rotate and slide forwards/backwards.

It was fixed on the chassis between the trailingarm mountings.

but personally I will still recommend renovating the original system first, and only resort to this modification if everything else fails.

In fact, if you get the ball joints under the gearlever and the ball joint at the far back of the rod just right, I think the above modification will actually inhibit gearselection, as It requires slack in both ends. (This is in fact the slack it "eats", making the gearchange feel better)

/Lennart
« Last Edit: December 08, 2005, 11:37:45 pm by Lennart » Logged

Lennart.Sorth@matrasport.dk
Murena 1983 1.9i silver // Alfa Romeo Giulietta 2.0d 2012 white // Smart 4two cdi 2010 blue //
Anders Dinsen
Administrator
YaBB God
*****
Posts: 2822



WWW
« Reply #8 on: December 09, 2005, 09:42:12 am »

.. the opposite effect as the sidewards movement, thus making it far less precise.
In fact, if you get the ball joints under the gearlever and the ball joint at the far back of the rod just right, I think the above modification will actually inhibit gearselection, as It requires slack in both ends.

Exactly my point! Smiley
Which means: Renew the system, don't make the modification.
Hwr, I'd still like to see the mod.
Logged

'82 Murena 2.2 prep 142
'01 Grand Espace 24v
'08 Smart Fortwo 0,8 cdi
hru
Sr. Member
****
Posts: 171


Murena Lover :-)


« Reply #9 on: December 29, 2005, 10:37:38 pm »

My car has a relativ low milage (33K)
I have only been driven it for about 300 kilometers. It seems to be better now, when it has been used a little.
I will maybe try to work it over a little with oil and/or grease in the junctions.
Logged

Matra Murena 2.2
Anders Dinsen
Administrator
YaBB God
*****
Posts: 2822



WWW
« Reply #10 on: December 30, 2005, 09:24:32 am »

My car has a relativ low milage (33K)
I have only been driven it for about 300 kilometers. It seems to be better now, when it has been used a little.
I will maybe try to work it over a little with oil and/or grease in the junctions.


Oil may help to eliminate friction, but make sure it is compatible with the nylon bushings.
Logged

'82 Murena 2.2 prep 142
'01 Grand Espace 24v
'08 Smart Fortwo 0,8 cdi
Roly
Newbie
*
Posts: 7


I'm a llama!


« Reply #11 on: January 24, 2006, 04:47:39 pm »

I had a very sloppy gear stick and imprecise gear changes.  Also, in first or second gear the stick was under my right knee.

I started off by changing the rear ball joint.  This didn't really make much difference.  Changing the top hat bush at the bottom of the gearstick made no difference at all.

I then replaced the three threaded link rods and all of a sudden things are a whole lot better - much more precise changes but the slop in the gearstick is still there.

Last night I removed the gearstick and found there was an awful lot of play in the nylon ball and cup assembly.  I ground the cups down until the play was gone, made some cardboard spacers (all per Roy's site), lubricated and reassembled it.  At the same time I welded together the two sections of the gearstick that slide up & down one another (for reverse gear selection) and cut off the reverse gear gate.

The difference these last two steps have made is fantastic.  It works like a proper gearchange!

Only problem is that the stick is still under my right knee.  Not as much as before but it's there.  It looks like this is how it should be too as the stick is mounted angled slightly towards the driver.  So do I get my adjusting hammer out?  Or is there a more delicate fix?

Cheers,
Roly

Logged
Anders Dinsen
Administrator
YaBB God
*****
Posts: 2822



WWW
« Reply #12 on: January 25, 2006, 01:59:50 pm »

It's great to read about your experiences, thanks for sharing it! Smiley

Only problem is that the stick is still under my right knee.  Not as much as before but it's there.  It looks like this is how it should be too as the stick is mounted angled slightly towards the driver.  So do I get my adjusting hammer out?  Or is there a more delicate fix?

Maybe the long rod B is bent towards the right (i.e. find the adjusting-hammer). Or it's turned so that A is not vertical. Or rod D is too long. I'm referring to the diagram (far) below Smiley
« Last Edit: January 25, 2006, 02:46:26 pm by dinsen » Logged

'82 Murena 2.2 prep 142
'01 Grand Espace 24v
'08 Smart Fortwo 0,8 cdi
Anders Dinsen
Administrator
YaBB God
*****
Posts: 2822



WWW
« Reply #13 on: March 10, 2006, 12:00:11 pm »

A short note to inform that I have changed my description of the system below because I now understand that it's the rotation of the long rod that lifts the selector in the gearbox. As Lennart correctly pointed out.
Logged

'82 Murena 2.2 prep 142
'01 Grand Espace 24v
'08 Smart Fortwo 0,8 cdi
GP
Guest
« Reply #14 on: October 03, 2009, 01:16:02 pm »

Hi all,

A vey old topic I know, but I thought as no pictures were ever provided of gear linkage modifications, I would attach some of the very simple modification I did some years ago to my standard gear linkage. (Having serviced and adjusted the linkage for optimum performance first!)

N.B. If you do not have the lower "Cross Brace"  fitted to your car, obviously you cannot carry out this modification.

I utilised an E.O. 22mm Gr3PP Plastic Pipe Clamp (Available in any good Norwegian Shipyard when the storekeeper is not looking  Wink )

The 22mm plastic hole was drilled out to 25mm  + to give a loose fit around "Rod B".
Two 6mm holes 33mm apart were drilled centrally in the cut out in the "Cross Brace" above "Rod B".
The assembly was then fitted around "Rod B" with a good application of grease and bolted to the "Cross Brace" with longer M6 x 60mm bolts and nyloc nuts.

It had great effect in minimising sloppiness and firming up the gear lever operation.

Question:

I was told recently by Titus Taylor that he had seen a car which had the outer connection point of linkage "Rod K" moved closer to the pivot point of "Arm G" which sits on top of the gearbox. This effectively created a shorter throw of the gear lever to change gear, ie. a quickshift. (A bit more arm effort may be required though, which I am not bothered about)

Does anyone have any further information on this, a picture or dimensions about this modification, before I set about driliing holes everywhere, failing miserably and go down the pub instead?

Cheers,

Graham
« Last Edit: October 03, 2009, 01:20:32 pm by GP » Logged
Pages: [1] 2 3 4 Print 
« previous next »
Jump to: