Pancake or bellmouth?

[Atoll]

Back in the day we never used air filters instead we preferred bellmouths fitted to our carbs probably for a more sporty look. My A7SS has a concentric carb fitted and the bike has a sporty look as below.
Question is do I fit a pancake air filter, bellmouth or lesve as is? Thoughts guys. Thanks.

[Triton Thrasher]

Why do you need someone to tell you what to do?

[Topdad]

TT, I don't think asking peoples opinions and then making up your mind is the same as asking us to tell Atoll what to fit ?  Personally I've got a concentric on my A10 ran without any filter until 4 mths ago then I fitted pancake type and it improved the response and smoothed out the acceleration so I'm happy with it  ,hope that helps.

[Black Sheep]

My A10 has a bellmouth, the A7 a vokes filter, the Velo its original filter, the B31 a bellmouth. Decisive, me? 

[Billybream]

As Topdad, I.ve never ran my Super Rocket
with an air filter, and that's how it left the factory, but after concentric overhaul this winter added a pancake version from Burlen.
Took me a while to get correct running but now pleased with set up.

[RayC10]

Wonder where all the standard air filters ended up from the swinging arm A10s? I can remember junking them thinking that  bell mouth would give more performance, stupid boy then. I would certainly fit a pancake, why not? On a similar note, I haven't seen a Gold Flash with a fully enclosed rear chain since I hacked mine off in 1970 something...again, stupid boy!

[tinu]

I‘m with pancake... after cleaning the carb trying to set up properly. Before that I was very happy...

[JulianS]

The standard air filters were difficult to get back on due to the rubber connection and lack of space, thats why a lot were junked. Unfortunately the monobloc used was for a rubber connection and not threaded so you could not screw on a bell mouth.

The lower section of the rear chaincase was (and still) is difficult to get back on, aligning the 2 parts of the tongue and groove assembly. Hence some did not bother and they got junked. A number of new old stock top sections come up for sale on ebay, but so far have not seen a a lower section.

[Atoll]

TT, I don't think asking peoples opinions and then making up your mind is the same as asking us to tell Atoll what to fit ?  Personally I've got a concentric on my A10 ran without any filter until 4 mths ago then I fitted pancake type and it improved the response and smoothed out the acceleration so I'm happy with it  ,hope that helps.

Thanks Topdad just the kind of answer I was looking for and not an answer ti a question I never asked. I will of course make up my own mind as you say and was just looking for responses from those who have experience of using either or both and you replied for which I thank you. Cheers.

[Atoll]

Thanks to all those who answered my question with a positive response. Much appreciated. I will have a think but the pancake sounds a good option even if a bellmouth looks more sporty.
Cheers.

[JulianS]

I use an S and B make pancake supplied by Hitchcocks. More robust than the type with chrome grill Had one fracture through vibration), washable and claimed to offer minimal resistance to air. Works fine. Does need a screw on adaptor.

http://accessories.hitchcocksmotorcycles.com/accessory-shop/air-filter/13585

[Triton Thrasher]

Short bell mouths have no performance advantage over just the bare carburettor, but that’s not what you asked.  You are after “performance looks.”

Velocity stacks on twin carburettors can increase bhp at some rpm, if you put time and trouble into it. I doubt that you’ll ever get any benefit on a single carb twin cylinder bike.

Late 1960s pancake filters are slightly restrictive on a 650.

[edboy]

i couldnt get the mixture right with the standard gold flash filter and a 2 into one. monobloc too rich, so use a bellmouth jubilee clipped to the standard carb. so far so good.

[muskrat]

G'day Atoll
Down here with all this beautiful fresh clean air I don't use filters on either A7/10. All the junk in the air up there would get stuck in my throat :-). I use bellmouths (velocity stacks) on my twin carb for tuning the inlet tract length. Doubt if any performance will be gained on a single carb head. Been running the plunger filter free for 30 odd years, hasen't killed the bore/rings yet.
Cheers

[Rex]

My plunger A7 has just been fitted with a new Amal Premier 600 series and space is tight between it and the down tube. A small bell-mouth would go in but is there an option for an after-market air filter?
{There is no trace of the original plunger air filter assembly}