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Bfitz241
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Joined: 02-05-2015
Location: Saint Augustine, Florida USA
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I searched for this so forgive me if I missed it.
On my DHLAs, direct your attention to the coupling between the front and rear carb [slave and master]. The coupling has 2 springs, one on the pin on the valvecover side, and the other as a springloaded screw for balancing. The pin on the valvecover side is sufficient to to open the master enough to make setting the idle impossible. I've rigged up a return spring to pull it back, but want to do it right. Are there any other springs besides the return springs on the back of each carb? Keep in mind I don't know if I'm missing pieces. THanks

subwoofer
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There should and must be a spring from the throttle linkage to the air filter box, otherwise the drag in the cable will prevent the throttles from closing. Makes for interesting driving, I can guarantee you that...

--
Joachim

Jim Ketcham
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The "throttle lever return springs" number 16 in parts manual is the only return spring I have on my JHs. The throttles snap close easily with quite a bit of force. If throttles do not snap close easily you may have misaligned throttle plates, bent throttle shaft, bad bearings... I will mail you some pics of my setup if you pm me with your email address.

Although I did see a setup like subwoofer refers to I believe it was added by the owner and I can't find any reference to one in the parts manual. Maybe Tim Engels can comment.

Bfitz241
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Thanks to all who commented. Got it running and synced my carbs. Went very easily, took longer to get heat into the engine than it did to set the carbs. 800 rpm idle, 3 1/4 turns on the idle mix screw, idle bypass just open. Runs really well. Now to fix the cold start jet [ too big] and accel pump jet [too big]. I'm almost positive the idle jet and main jet will prove to be [that's right] too big.

As to that spring I hooked up, I think I'm going to add a brace or bracket across the air cleaners [K&N] and continue to use a return spring for the throttle cable, plus the ones on the carbs simply for redundancy's sake.

subwoofer
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I bought a set of Spec 5 carbs and an Eclat airbox together, the spring sat on the airbox. I didn't figure out what the spring was for until I drove it for the first time after the swap. Having to use the brakes to stay under 30mph was a bit, whatshammacallit, interesting.

Don't set the idle too rich or it will load up and die when idling for a bit of time. Especially if you suddenly find yourself in stop-and-go traffic and you still have the original Lucas starter.
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Joachim



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