Single to Dual Amal Setup

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Tornado said:
OK new issue:

With grip to splitter adjuster piece fully undone save for half a turn and the carb top adjusters fully unwound, I'm getting a good 3/8" slack with grip fully rotated to throttle closed position. This means rotating roughly 20 to 30 degrees before any tension on cables. Are my cables wrong? My supplier is usually good with these details. What are correct dimensions so I can confirm?
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Is the two into one throttle cable junction box the original or a replacement type,there are different inner cable measurements for different junction box types.
 
Tornado said:
Dual amals are mounted. What a pain doing the Allen bolts. I had manifold already on carbs first. Found only a 7mm wobble Allen key would work as proper 1/4" key I have is not wobble type. I think a shorter/ground down key might also work. Since I'd already fitted cables, then learned splitter had to come off to pass short cables through the headsteady brackets. Splitter ends up just rearward of front tank mount flanges.
Suggestions for grip cable routing?
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You need a shorten allen key, the orginal tool kit that came with my new Norton had the shorten allen key in the kit for the manifolds, its the only tool I have left from my orginal tool kit.

Ashley
 
HRD said:
Is the two into one throttle cable junction box the original or a replacement type,there are different inner cable measurements for different junction box types.
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It is a new splitter, black plastic. Unsure if Amal or some other make, baggy didn't have labels.
 
texasSlick said:
Sounds like you need to shorten up the cable by moving one of the nipples, either at the splitter, or at the throttle.

I would rest each slide in turn, on the throttle stop screw, then while holding a finger on the slide to prevent it moving, adjust the carb adjuster until you get barely perceptible play when you push and tug on the cable sheath at the carb end. If this requires turning the adjuster fully out of the carb top, then the carb to splitter cable needs shortening.

After getting the excessive play out of both carb to splitter cables, then work your way back to the throttle.

Slick
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Seems to be case but I. Will contact supplier to see if there was a mistake before cutting anything.
Curious, is there a way to add some sleeve length by splicing in a short bit of extra sleeve? Seems that would achieve desired free length without needing to learn how to fit a nipple.
 
FWIW, I'd say that it's not really "fair" to go from a good-running single Mikuni to original 932's with new slides and get the improvement you may be hoping for. It is entirely possible that the original Amal bodies are warped and the new slides won't mate as well as they should. I'd suggest a new set of Premiers for this "re-conversion." That being said, I realize that if you are just doing it to try out, it's a lot cheaper to NOT buy a pair of new carbs. ;)
 
Fullauto said:
First prize was one Anal, Second prize was two Anals.
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There speaks the voice of experience!!! Ha ha
Whilst my head agrees with you my heart tells me two amals and use the bike for what it's designed for
 
baz said:
There speaks the voice of experience!!! Ha ha
Whilst my head agrees with you my heart tells me two amals and use the bike for what it's designed for
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AND... the twin Amal bike - ASSUMING the carbs are in like-new condition and properly jetted - will walk away from the single Mik bike at WOT as the RPM passes 4k. Also, don't expect a stock 850 with the single Mik to do the ton...at least in any reasonable distance; the twin Amals will have no trouble.

Whether you care about doing the ton is a different issue! ;)

Of course, the single mik with a real choke is a lot less messy for starting than dual ticklers!
 
We must be careful here as it could degenerate into a single verses twin amal debate (again)
The bloke wants to try twin amals on his Norton
Everyone has an opinion
I'd say go for it,sure if the carbs are worn it'll play up low down but the top end will still be there
On my own commando I have gone back to twin amals and the bikes carburetion is spot on, although I will at some stage re fit the 40mm pumper when my carbs wear out
Cheers
 
Tornado said:
With grip to splitter adjuster piece fully undone save for half a turn and the carb top adjusters fully unwound, I'm getting a good 3/8" slack with grip fully rotated to throttle closed position. This means rotating roughly 20 to 30 degrees before any tension on cables. Are my cables wrong?
Click to expand...

The upper cable is possibly wrong as there are two different inner cable lengths (regardless of overall length).

= 3.06" standard, and 2.44" for the later 'Quick action' twist grip.


https://andover-norton.co.uk/en/shop-details/15634
https://andover-norton.co.uk/en/shop-details/16328
https://andover-norton.co.uk/en/sho...tgrip-7-8-bars-amal-type-364-replica-06-4600-

Edit: 'Throttle' and 'choke' lower (carb end) cables have different length inners.
https://andover-norton.co.uk/en/shop-details/16698/throttle-cable-carb-end-03-3145-
https://andover-norton.co.uk/en/shop-details/16699/air-cable-carb-end-03-1613-03-3144-
 
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Thx LAB for those measures. I will check what I have.
Do I take the nipple lengths into account for the free length dimension or just the cable section between nipple and sleeve?
Watched a few viddys on making up cables. Seems nipple can come off with heat and knocking with a pair of pliers. Refitting by flaring out strands to hold nipple then soldering to make fast. Can give it a try with older cables. Got a couple HiRider length off bike someplace.
 
Tornado said:
Thx LAB for those measures. I will check what I have.
Do I take the nipple lengths into account for the free length dimension or just the cable section between nipple and sleeve?
Watched a few viddys on making up cables. Seems nipple can come off with heat and knocking with a pair of pliers. Refitting by flaring out strands to hold nipple then soldering to make fast. Can give it a try with older cables. Got a couple HiRider length off bike someplace.
Click to expand...

After making a couple of throttle cables some of the things I learned were,
1) Use a heat sink on the running cable side of the nipple. If the cable gets hot solder can flow into that area and cause a stress point.
2) Keep the factory nipple on the carb end. If the DYI connection breaks the nipple won’t drop into the carb
3) Use a dab of flux on the cable before you solder
4) If the cable is stainless you will need special flux and solder.
5) Clean and degrease the area well
I’m sure there are other things to worry about, but that’s all I recall

This might be helpful
Single to Dual Amal Setup


Pete
 
So the upper cable has the wrong grip nipple...it is a thinner disk than my older single carb length cables, basically the same as what the choke control uses. And the bag it came in indicates it's for a Triumph. Free end length comes out as here (lower cable is dual type with adjuster, upper is single carb cable) with adjuster at max unwound:

Single to Dual Amal Setup


Or with adjuster full wound in:
Single to Dual Amal Setup


Note nipple ends compared to single carb cable above it.
 
Yep , have dealt with all those issues in the past , I now have a collection of cable ends in a baggie ... the instructions above are excellent , you should use them as reference .... you getting very close to having a dual carb setup .... good luck !
 
OK talked to supplier and we discussed how to make a more informative measure of the excess. With the cables all connected up to carbs, pull the sleeve away from grip until free movement gone, before throttle spring tension occurs. Measure how much excess inner cable emerges from grip mount. Here's what. I got at both extremes of upper cable adjuster settings:

Single to Dual Amal Setup

Single to Dual Amal Setup


So around 3/4" to 1-1/8" taking the second band on the sleeve endcap as the datuum point (it sits just outside the grip mount recess when sleeve is fully inserted).

Supplier says he can make up a new cable and send it out today.
 
If I was doing that, I would not use a junction box. Thomaselli sell twin cable quick action twist grips and most sellers of Japanese bikes have suitable separate nylon-lined cables for sale. I have fitted twin carbs in place of a single carb on Triumphs and not noticed any difference. It is easier to tune a single carb and a well tuned single carb is probably better than sloppy twin carbs.
 
My Rapide had nylon lined cables. They are good until used in an all day rain.
When in that situation the hygroscopic nature of nylon caused swelling which in turn caused the throttle to stick open.
I had this problem on a couple of trips then switched all of the cables over to Venhills Featherlight Teflon lined. Teflon is even more slippery than nylon plus it isn't hygroscopic.

Problem solved.

Glen
 
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I will only use Venhill Featherlight, unless there’s no other choice. The difference in feel and lightness is noticeable.
 
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