Britbike forum Forums British Motorcycle specific Brands Norton bulletin board AMAL carbs?

My 1971 Norton 750 Commando carbs were sticking shut. I took them apart,cleaned with carb spray, didn't work!. Brought bike to mechanic. He tells me that I need new ones. New design bla bla bla. Now 3 years later he still has the bike. Tells me he can't get the carbs because of Covid Bla Bla Bla. I haven't looked but are they so hard to get? I owned the bike since 1972 and want to ride again. I'm in Los Angeles.
Any advise would be appreciated.
Please and thank you!

Try: https://www.gregmarsh.com/MC/AmalCarbs.aspx

I just googled "AMAL premier Norton Commando" and the first page popped with 5 trustworthy American shop sources for them, and of course eBay. Not hard to find at all. Your guy is maybe feeding you a line? And in my google search, the first source is in LA--Franz and Grubb out in the San Fernando Valley https://www.fagengine.com/products/...ntric-carburetors?variant=24105692463204 This link is to 932s for an 850 but they no doubt have your 750 covered too, and they would install them for you too. Unless you are mechanically inclined, that might be the best course. Perhaps the time has come for you to reclaim your bike and move it to another more trustworthy and diligent shop?

And my unsolicited opinion is, get the premiers, the moderate extra extra cost is worth it.

Carb slides getting stuck on AMAL's is usually a symptom of the body being distorted through overtightening the mounting flange nuts.

The distortion is recoverable but don't try flattening the mounting flange with a file or emery cloth on a flat surface.

What you need to do is have a mock slide made from alloy a couple of thou thinner than the original slide. A hole is drilled through the mock slide central so that its Concentric with the air intake.

Next, a bolt is inserted through the mock slide and the manifold mounted on a thick steel plate with a hole for the bolt. A nut is added on the other end of the steel plate and the bolt is tightened. This pulls the manifold straight again and it's useful to add a feeler gauge on either side of the manifold (0.011?) as the alloy manifold may pull back.

See This post from years ago where John Healy gives better instructions,

Thanks gunner, an excellent bit of information.

If you can afford them. The new primers are the way to go. Unless you can find some new carb bodies.

Excellent advice.

Here's photos of a fixture I have used a number of times, made from whatever was laying around. The idea works very well but the whole thing needs to be baked at 350 degrees for a half hour or so, checked, re-tightened, and baked some more. It completely fixes sticking and also seems to help idle and off idle running. Highly recommended IMHO.






In fact, I have used this same basic strategy on seriously warped Weber carb bodies (high risk unobtanium) with very satisfactory results.

I've found with a couple of old Concentrics that were sticking on arrival as fitted that just removing them
and LIGHTLY tweaking them up that they freed off completely.

But maybe there are levels of ham fistedness, and they hadn't been warped beyond workability ...

P.S. 3 years !!!
I'd have been getting edgy after 3 days ...

Hi Leftcoast,
I think it is past time to collect your bike and find another shop. Anything left that long can become a "parts donor" for other jobs. You do not want that to happen. Be sure to check it over carefully before you take it out of that shop.