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Tips
Tips

TR2/3/3A choke operation from the factory !!!!

Randall he probably does not have the long clevis pins and the linkage choke connector on the outside of the frame. The whole deal looks wrong and counterintuitive. Plus the cable has to be just right at the clamp with about 2 inches of cable sticking out from the sheath and about ÂĽ inch sticking outside the sheath holder then that 2 inches hooked onto that special pin.
 
Randall he probably does not have the long clevis pins and the linkage choke connector on the outside of the frame. The whole deal looks wrong and counterintuitive. Plus the cable has to be just right at the clamp with about 2 inches of cable sticking out from the sheath and about ÂĽ inch sticking outside the sheath holder then that 2 inches hooked onto that special pin.
Good point! Here's a photo of the later setup (from Practical Hints 6th ed). Notice too how the link runs entirely behind the levers, instead of straddling them. Believe it or not, it works better this way.

sRxPxnb.jpg
 
John, I thought there was a second ground wire at the tank sender that went down underneath one of the tank strap bolts ?
Not originally, AFAIK. But IMO it is a very worthwhile modification. I also added a separate ground wire for all the rear lamps, to the same ring terminal on a tank strap.
 
Yes that is it—hook your choke up just like that, and oil the cable plenty, and your choke should work where you can pull it with one hand!!!!
 
...Notice too how the link runs entirely behind the levers, instead of straddling them...

Hmm. I've studied that photo (it's up there with Nessie swimming and the Zapruder film in my book) and I can see that the rear one is indeed inboard from the arm, not straddling:

NsIvrZx.png


But when I look at the front one it appears to me that it straddles:

ldBl2pY.png


That bolt & nut have to clamp down on the cable to hold it so it makes sense (again, to me) that the bolt would have to be tight but the arm would need free movement so it goes inside the fork.

In the end - the best set-up is the one with the easiest movement, no binding.
 
Yeah, I find that somewhat puzzling too. Best I can make out, the photo has been carelessly retouched and some of the features are simply missing. My guess, they started with a photo that did not include the cable at all, and added (most of) the cable to it.

To add to the confusion, the SPC shows the pin oriented the other way!

But it's not a bolt, the original part has a long smooth pin on one side, which obviously goes through the lever and clevis and is secured there by a cotter pin. The other end is threaded, and there is a hole for the cable to pass through and be clamped by the nut.

Here's a shot from an earlier manual, which more clearly shows the clevis

 

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Since I am reconstructing my carbs I looked at this area. Having the forks not straddling the jet lever seems very odd. I looked in Bill Piggots book ( the TR3 one) and the only pic I could find there , at the bottom of Page 65, showed the rear lever being straddled. Not sure how authoritative that is, but it is logical. I have to replace that lever as a PO had used a wood screw as a cotter pin and the hole was way out of round. I guess you put it where it works with least friction.
 
Don't rely too much on the photos in Piggot's books. The one you refer to
on P. 65 has at least two other "in-accuracy s" His written information is
very reliable, so IMO that makes up for the photos.
I set my choke up so the distance from closed to the first notch takes
up the clearance on the fast idle cam so the first notch is still "no choke"
I pull it (straight) out to the 2nd or third notch to start, then twist it back
to the first notch for a fast idle 'till it warms up enough to drive.
All my linkage is set up according to the later "Hints" (6th ed.) but
I still found it difficult to pull to the 3rd notch. So I got lazy & disconnected
the link from front to rear carb. Choking the front carb only works
fine. (A couple more cranks than before but only when the car
hasn't been started in several days)
Frank
 
On mine I could see there was enough slop in the connections that the front carb was getting 'choked' quite a bit before the jet began to pull down on the rear carb. To reduce this I put a bit of pre-load on the linkage by lengthening the rod to the point where is was just about to move the rear jet. That way I get pretty good action on both jets.
 
I never would have believed those choke forks and rod sit on the outside of the choke arms had I not purchased new and bought an old choke original clevis pin that is so long it would only fit and work that way. All that linkage is so counterintuitive, right down to very large holes that just slop around so the linkage does not bind. My mind likes bearings and things that roll in exact spaces.

I live in a very damp cold wet climate in the winter and I love driving my tr3 more on cold clear days more than summer. If I did not have a choke that worked as good as it could, I would be out there squirting starter fluid in there to get it to fire; the voice of experience.
 
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