2500M Throttle cable/linkage

[LSRbbs]

Can someone post a picture of the stock throttle cable/linkage setup for a 2500M? Prior owner on mine converted very poorly and it doesn't have a return spring so idle tends to hang a bit and I want to return it to stock. Looking at the photocopied parts manual it looks like TR6 with someway to connect it to a cable, this is the part I'm really interested in a picture of.

Neil.

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[Slow M]

Hi Neil,

I'll email a friend, to see if he would be able to snap a pic of his.

Best,
B.

P.S. Welcome to the forum.

[Adrian@]

Adrian@

[Hansoplast]

Hi Adrian,
Just a picture or a real car in your garage?

Cable runs different as original Triumph so the owner was mislead in the handbook.
Tvr had his own route presumably. Simple without to many corners.

Hans

[Adrian@]

It is a car that I am working with the owner on at the moment.
It is a 72 2500M car and as such Triumph saloon 2500 engine, more likley to be as fitted to a Vixen 2500, rather than the later TR6 export engine set up we see.
Adrian@

Edited by Adrian@ on Wednesday 16th July 17:29

[jastx]

Neil, I have a '77 2500M. I will take a photo of the linkage when I get home.

John

Update - went home for lunch.
A difficult area to photograph. I hope these pics help. As you can hopefully see, a sort of V-shaped bracket holds a spring-loaded pivoting "triangular-ish" piece that is connected to the carburetor linkage. The throttle cable is fastened to a square steel "rod" at one end with a set screw. The square rod has a hole in it at the other end that fits over a pin from the pivoting triangular piece with a cap on the pin that secures the square rod but allows free movement on the pin. Applying throttle pulls the rod horizontally, which pivots the triangular piece connected to the carburetor linkage, that then operates the carbs.

From carburetor side:


From engine side:


Another from engine side:

Edited by jastx on Wednesday 16th July 18:16

[Slow M]

jastx said:

Neil, I have a '77 2500M. I will take a photo of the linkage when I get home.

John

Update - went home for lunch.
A difficult area to photograph. I hope these pics help. As you can hopefully see, a sort of V-shaped bracket holds a spring-loaded pivoting "triangular-ish" piece that is connected to the carburetor linkage. The throttle cable is fastened to a square steel "rod" at one end with a set screw. The square rod has a hole in it at the other end that fits over a pin from the pivoting triangular piece with a cap on the pin that secures the square rod but allows free movement on the pin. Applying throttle pulls the rod horizontally, which pivots the triangular piece connected to the carburetor linkage, that then operates ...

That's exactly what mine looked like. Well, except the texture and colour. Mine was laden with filthy, black grease.

Best,
B.

[LSRbbs]

Jastx,
Thanks, that's exactly what I needed. That's interesting that they changed the geometry by using the original location for the return spring and adding the post for the cable attachment. That'll be plan B as I've got the parts to replicate the TR6 setup and made a threaded end I can solder onto the cable that will screw into the original ball joint. I might steal that return spring idea as it looks easier than the TR6 setup as finding the right spring has been difficult.

Did they tin the end of the cable to keep the set screw from tearing up the cable wire? Just curious.

Neil.

[jastx]

LSRbbs said:

Jastx,
Thanks, that's exactly what I needed. That's interesting that they changed the geometry by using the original location for the return spring and adding the post for the cable attachment. That'll be plan B as I've got the parts to replicate the TR6 setup and made a threaded end I can solder onto the cable that will screw into the original ball joint. I might steal that return spring idea as it looks easier than the TR6 setup as finding the right spring has been difficult.

Did they tin the end of the cable to keep the set screw from tearing up the cable wire? Just curious.

Neil.

I don't know. I had the carbs off to rebuild them and had the throttle assembly off, but that set screw was really tight so I decided not to mess with it.

John

[Grantura MKI]

There is a linkage system list on ebay USA if that helps?
Best,
D.

[eric0]

Standard cable set-up on mine, TR6 long . The mechanism pictured in the posts above is shown as part of the rod type set-up in the TR6 manual?

Good job i went out to take these photo's, It's just started raining and i'd left the roof open.

Edited by eric0 on Saturday 19th July 00:54

[eric0]

Standard cable set-up on mine, TR6 long . The mechanism pictured in the posts above is shown as part of the rod type set-up in the TR6 manual?

Good job i went out to take these photo's, It's just started raining and i'd left the roof open.

Edited by eric0 on Saturday 19th July 00:58

[jastx]

Grantura MKI said:

There is a linkage system list on ebay USA if that helps?
Best,
D.

Here - http://www.ebay.com/itm/TVR-2500m-CARBURETTOR-LINK...

[LSRbbs]

Yes, I saw that but looks like either modified or later version as it looks like some type of rod (I'm thinking a mix of tvr and tr6?)

Actually, I bought another 2500m linkage off ebay the week prior to that one being posted. Bought it because it had everything but the connection to the cable and it was in rough shape. The brackets and bell crank cleaned up. Had a machinist buddy remake the threaded portion of the unobtainable bit that goes between the two carbs. New ball joints and bolts and reusing some bits off my original and mangled setup. I took a 1/4-28 bolt drilled through the long axis and will solder this to the end of the cable so I can screw it into the ball joint. I ended up drilling/threading a new location for the ball stud like the earlier pictures to have enough throw so it didn't hit where the cable end adjuster is located (and I'm guessing that's why they did too). Cable housing and assorted bits showed up today so I should have it back on the road tomorrow. Thanks again for the pics, exactly what I needed.

Neil.

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