Forum

[Beezabryan]

Because it is not broke I will not be mending it but if i did go down that road I would opt for a monobloc.Why? for no other reason than to me it is more pleasing to the eye than concentric. Does that make me eccentric?

[Pathfinder856]

Fair enough,
I think that the Monobloc is a nice looking carb, and suits the fifties style
I wanted the look of the Concentric so chose the premier.

[mauri]

if you have not specified your set up on purchase, exhaust type/filter/cams…..



then part nr am/622/502/XX is one to hold on to.

XX stands for the jet size, they start of at 15(one line) and go up to 23(five lines).

it will come probably with a 17(two lines) which with a standard exhaust and filter will be barely just.

check the main jet also, should be at least a 210.



the correct description of a monobloc is a diffuser tube, calling it a carburetor i way over stated.

[Pathfinder856]

Thanks for your help, that is useful.
However my plans are on hold for a few weeks, there was a mix up and there are no Premier Carbs in stock so I have a Six to Eight week wait for one!
So plenty of time to sort jetting!
My bike it a 500 T, the watsonian built trials model, it has a freer breathing silencer, one of the Amal style Pancake air filter housings , with a remove able element .
So it is slightly Non Standard!, but is how it was supplied new by watsonian Squire .
I'll have to think of some other mods to do for the next few weeks !!!

[PeteF]

High capacity oil pumps? What on earth for? The engine gets more than enough with the standard pumps.

[Thack]

They're for people like me who like to whinge endlessly about the crap lubrication system and love to fix things that aren't broke!

[Norm]

I can't imagine why people want to fit hi cap pumps to a motor with a floating bush fitted, cold start, particularly in places where it gets cold, start up, cold oil trying to be forced through a floating bush, big load on the pump spindle, particularly if you happen to rev the motor before the oil has warmed up. Roller big end no probs with the high caps

[Revband]

But Norm, that's the way with some, if it aint broke keep fixing it until it is, every mod is a good one even when inappropriate. More oil has to be good even though the engine doesn't need or want it and the oil pumps just lift of their seats and don't pump any more oil. I know, hat, coat, door.

[sofiaspin]

You have made a good choice. I am astonished at the negativity re the Mk1 as I have had five of these carbs on various bikes including a Venom, two Bullets, a Sunbeam S8 and an Atlas. Quality build, just get the jetting right and they work perfectly with an open pipe. Yes a flat spot now and then but they look the business particularly with a bellmouth. Ride it hard and enjoy.

[Thack]

"......and they work perfectly....... Yes a flat spot now and then......



That sounds like a contradiction to me!



By the way, wouldn't an open pipe be a bit too noisy these days?