30mm Delly with Muggy and Ancillotti???

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alanscottj
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Hi guys, do you think a 30mm Dellorto will be ok on a mugello 198 and Ancillotti exhaust? I know the recommended delly for an ancillotti is the 26mm but I want to put an expansion pipe on at some point so I am going to get the 30mm now to save changing it later. I have a 25mm on it at the moment and I know I am not using the kit to its potential. Any thoughts?
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joey
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...when you put the 30mm on you'll wonder why you pist about with a 25mm..enjoy
alanscottj
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joey wrote:...when you put the 30mm on you'll wonder why you pist about with a 25mm..enjoy
I bought the 25mm when I had a 175 kit on it, then got the Mugello and so on......I take it you mean the 30mm will make a difference?
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Minority
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Yes, you'll use twice as much fuel :lol:
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coaster
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I'd be tempted to go for a 28 PHBH with your setup.
storkfoot
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There's no recommended carburettor for any type of exhaust. There are carburettors that work well with certain combinations of engines and exhausts. So, a standard exhaust, Li125, 18mm Dell'orto work well together. Try taking the standard exhaust off that combination and putting a Franspeed Race pipe on, or a 30mm PHBH, and you'll struggle like mad to get the engine to breath right, or run well.

You have not said whether your carb breathes through the airbox. If it does, and you want to keep this arrangement, then steer clear of a 30mm carb IMO. A carb of that size needs much more air than an airbox with filter can provide.

The point about a 30mm carb being much more thirsty than a 25 is not necessarily true. A well set up 30mm carb can use less petrol than a badly set up 25mm.

Anyway, in answer to your question, a PHBH30 would, IMO, work well with the set up you talk about as long as its set up correctly and allowed to breath properly. If you do this change, the main difference you'll notice is more power at the top end.

So, if you spend your time riding hundreds of miles around the country to rallies with your throttle approaching wide open, go for it. If you favour rideouts and pootling around locally, I'd not bother as a 25mm carb (if its in good condition and set up right) is a good match for the combination you have.
Last edited by storkfoot on Mon Aug 18, 2014 12:17 pm, edited 1 time in total.
mark1
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I've got a Muggy 186, JL3 and a 30mm delly on. it runs a treat and doesn't drink fuel.
alanscottj
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storkfoot wrote:There's no recommended carburettor for any type of exhaust. There are carburettors that work well with certain combinations of engines and exhausts. So, a standard exhaust, Li125, 18mm Dell'orto work well together. Try taking the standard exhaust off that combination and putting a Franspeed Race pipe on, or a 30mm PHBH, and you'll struggle like mad to get the engine to breath right, or run well.

You have not said whether your carb breathes through the airbox. If it does, and you want to keep this arrangement, then steer clear of a 30mm carb IMO. A carb of that size needs much more air than an airbox with filter can provide.

The point about a 30mm carb being much more thirsty than a 25 is not necessarily true. A well set up 30mm carb can use less petrol than a badly set up 25mm.

Anyway, in answer to your question, a PHBH30 would, IMO, work well with the set up you talk about as long as its set up correctly and allowed to breath properly. If you do this change, the main difference you'll notice is more power at the top end.

So, if you spend your time riding hundreds of miles around the country to rallies with your throttle approaching wide open, go for it. If you favour rideouts and pootling around locally, I'd not bother as a 25mm carb (if its in good condition and set up right) is a good match for the combination you have.

My current set up is running through a remote RamAir filter - I have also decided to bite the bullet so to speak and have ordered a new JL3 pipe. Am going to run my engine in (just had full rebuild) using the current set up and then swap over to the 30mm carb and JL3. Then, all being well I will be making the most of the Mugello kit. Next stop - dyno (again!)
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