from the anals of amals

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May 4, 2006
after adujusting my valves and syncing my carbs (932's) for the 3rd time with no results, my bike still ran like hell. so.......i pulled the float bowls off and removed the jet holders and low and behold, sitting on top of the right one was a spray valve bushing. i had no idea what is was. with a mirror and flashlight i could see from the other carb where the part was to go and its orientation. with some locktite and a drift punch i carefully got it back into place, put it all back together and it ran as good as ever. what a relief! i was loosing faith in my aptitude for simple maintenance. anyway, this leads me to a question. some very reputable norton people i have been talking to are trying to steer me to a single mikuni conversion through stan at rocky point cycles. they swear by them and have been using them in the bikes since 1982 and all the ones they have built. i know it is some trade off for high end power. i do not really live at the 5000 rpm range. i hear they are hard to set up. does anyone have one that can tell me either way, positive or negative. my other option is re-sleeving, although i am concerned about the bushing. i contacted amr and have not heard back. i know from my lowend running that my slides are worn. 15000 miles. thanks in advance for any response. jerome
i got one on my 850 and love it - the bike runs better, idles better, and gets much better gas milage. you do give up a little overall acceleration, but since a modern sportin bike crotch thing thats only 400cc will out accelerate it anyways i wasn't to worried about that. It was a little bit of a bugger to set up - but not that bad - throwing it on was no big deal, and they typically come pre-jetted (if you want to really learn about jetting there is a great publication on mikuni's at victory libary -do web search, or member panic can tell you more about it i believe) -took me about 1-2 hr totally and a bit of fiddling to get it great- the ONLY thing i don't like about it is the choke operation-but stan has a little gizmo that removes it from being on the carb to a cable operation on the handle bar like the old anal set up
all i can say is go 4 it!
My Amals will get some 50mpg; I doubt that MIKs will top than that. My Amals have chrome plated brass sleeves from AMR and will probably last a very long time, I hope. So, I really don't see any advantage to running a MIK, plus it's not near as elegant as twin Amals.
Jason Curtiss said:
My Amals will get some 50mpg; I doubt that MIKs will top than that. My Amals have chrome plated brass sleeves from AMR and will probably last a very long time, I hope. So, I really don't see any advantage to running a MIK, plus it's not near as elegant as twin Amals.

to each his own - the guy asked about mikuni's i believe
I put a 36mm Mikuni on my 850 last summer and it works great. I could never get my Amals to idle right but then again, they weren't sleeved by the previous owner either. I have sleeved single Amals on all my other bikes and they work great and idle beautifully. I may try sleeving the Amals and put them back on the Commando at some point just for comparison.

Like some others have said, you will lose a bit of acceleration and a bit of top end with the Mikuni. However, if this is not a concern, it is certainly is easier to keep a single Mikuni in tune and they are high quality carbs. Many Commando folks have made this conversion and most seem to be happy that they did it so that probably tells you something. As to whether they look right on a classic British bike or not, that is only something you can decide!!
Jason Curtiss said:
Yes, I know he asked about MIKs but I couldn't resist making a plug for Amals.

I believe he also said he's considering getting his Amals resleeved :!:

Regarding that, I would recommend contacting Bruce Chessell/Triton Machining. He did my Amals and the bike runs great. And on my last ride they delivered 54 mpg. It's a one-kicker too, hot or cold. Pretty hard to improve on that I'd say :wink:

Bruce could probably take care of that bushing problem too.

thank you all for your insightful replies. it is truely a dilema. i read well into the archives last night and came out thourghly confused. today i had her out on a country road and the full throttle felt incredible, so gutsy! on the way through town, holding at 25 with the bike surging i felt frustrated. if i knew the bushing would hold through the riding season (i do have some journeys planned) i would probably wait till winter and resleeve. oh well, decisions like this i am finding hard to make. thanks again for the input, jerome
anyone thinking about the rally in capital reef, utah this july :?:
elegant - smellagante :lol:

go for the gusto
(as per sudco web site for alternative carbs)

Norton Commando Keihin FCR Carburetor Kit
Kit includes prejetted Keihin 35 FCR carbs, 2 K&N air filters,
throttle cables, and throttle housing. Requires Mark 2 manifolds

only about $t 1100 :roll:
Jerome, You'll find this carb thing stirs a big debate.
The INOA Tech Digest covers both the Mic and Amals and recommends both.
It also states it is 'hard to beat a pair of well set up Amals.'
The problem is that the Amals wear quickly and most are messed up.
So when someone throws on a Mic, it instantly runs better. That's because the Amals are wore out. Throw on a pair of sleeved / rebored Amals and wha la, it runs better also.

I've run em both. I wouldn't hesitate to run either. They both work well.
If you run a Mic, I would get the 90 degree ferrule for the top of the carb. This aleviates the kinked throttle cable. The other issue, unless you have a Mark 3, will be the key issue and old backing plate.

On the Amals, they'll slip right in, obviously with no mods.

Contrary to what others have said. On the same bike with a good set of Amals, I can get a better idle, with a little more snap at lower revs than the Mic.
This is due the the common manifold on the Mic. There is some reversion happening.

The Mic can be tuned very well and is less overal maintance down the road.

If you get your Amals sleeved, don't overlook replacing the needles and jets. They wear out also. Make sure you get the correct needle for the spray tube in your carb.
The 4 ring needle is for the cut away tube, 3 ring for the straight tube.
Whoever does your bore / sleeve job can set you up.
AMR and Bruce are both excellant.

Good Luck!!
I ran a Mikuni on my commando many years ago when it first became popular (about the time the tech digest first came out) It started easily and ran okay, but I then started riding with folks who rode in a more "sporting" fashion, and the Mikuni just didn't cut it.

Took the time to learn how to setup, sync and tune dual Amals (chrome slides from AMR) and have absolutely no need or desire to return to a Mickey Roonie carb.

My bikes now start easily, idle well, accelerate well and have great top end and mileage.
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