Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Carburetor

The Mikuni is a good carbs, but many Harley owner with S&S engine also use SU and seem's that work well after a fine tune the looking is better and the SU is more english

Advantage of Mikuni over an SU is availability and range of parts for tuning. The one I had on my Velo had so many jet and slide options it was bewildering!

But I don't think you can beat an SU for simplicity and reliability, not that many moving parts.

Are the M3Ws not subject to emissions control restrictions? Can a carb run cleanly enough to pass the tests?

you got the dark point, it's why i haven't get one in my 1340 Softail with my Knucklehead S&S replica , but according to friend witch have made the move it's easy to find all part you need.

in term of look they are also unbeatable (in my eyes)

Here motorcycles are not subjected to emission tests at our equivalent of the MOT.

Bikes have to be Euro-4 compliant emissionswise OR have been registered for street use before Jan 1st 2017, however.

How much of the British legislation will be redone at Brexit?

Mine has been registered since 2013, so no worries. Don't think I will remove the cats anyhow.

I'm not sure BREXIT will change too much legislation for the forseeable. Otherwise UK standards will become another set for imports to adhere to, and another set for those who export to adhere to (UK sales and European exports).

In fact, the cynic may even suggest that going forward we will have the freedom to chose exactly what we want, but in practice have absolutely no say in shaping what we actually [voluntarily] choose to inherit from the EU.

(This isn't a political statement, merely a pragmatic business statement)

M3W in the UK are not subject to emission testing at the MOT. As I found out last year when the tester tried to get my car to pass the emissions test and eventually gave up, post test I found out that it was not required.

Well stap me vitals, I'm amazed.

If the ECU goes south, this mod definitely looks like the way to go. What throat size is recommended for the carburetor option? I have boxes full of 1-1/2" SU's , would probably need to fabricate manifolds, one for each cylinder, in which case, 1-1/4" might be better. Perhaps a Weber would do better.

Remember, you still have the ignition to worry about. I know that there's a company called Thunderheart that sells standalone ignition systems for late model ECM controlled Harleys for use in like a custom bike. A Thunderheart ignition and a carb is all you'll need at that point.