pods vs bellmouths

[Agemax]

what is the difference on a street bike? obviously i would need to mesh the bellmouths to stop birds.frogs.hedgehods, cats and what haveyou from climbing in and making my engine their home.
are they easier to set up the carbs than pods or does it make things all get a lot trickier?
i have a 1085cc gs with standard 26mm vm's with stage 3 dynojet kit and a harris race pipe
cheers

[gshub]

K&Ns V Bell mouths

I run my 1085cc on stock 28mm carbs oval K&Ns ,like to put Bell mouths on but i find have to clean my K&ns out twice over the summer months ,flys and grit then i get a flat spot at
3000rpm Gs want to wheelie.
Gs runs best with K&Ns tried stock airbox on but got a mega power loss in mid range.

[Buffalo Bill]

From car experience…

Remembering the research I did for my race car back in the early '90s. The bell mouth or velocity stack will give great results for a narrow RPM range. That chosen RPM will determine what length and shape to use.
However performance gains are negated by any kind of screen or filter placed over the mouth.
I chose to use a midrange intake manifold and the OEM air filter box for street use, then switch to an unfiltered air horn for racing.
Bill

[Agemax]

so a fairly open mesh screen wont affect it too much?

[sharpy]

Whats wrong with front half of air box and big K&N filter clamped onto the back? Works a charm with my 29mms and will have same setup with 33mms one day. Just have to Zip tie the battery in its box to stop movenent. And you still have the standard stacks that are inside the airbox as standard

[Agemax]

i have no standard air box, just pods. just wondering about velocity stacks as a replacement

[sharpy]

i have no standard air box, just pods. just wondering about velocity stacks as a replacement

Would never runs just stacks on the street. Way too much crap floating around when ure on the raods.

[Agemax]

Would never runs just stacks on the street. Way too much crap floating around when ure on the raods.

i will rig up some mesh filters

[Buffalo Bill]

That's the best set up I've seen!

Right On Bro! Your set up has everything: velocity, torque and filtration. I like the carb vent hoses too, or are those crankcase vents?
It was only by tilting the engine way forward that Yamaha was able to add an intake scoop and raise air box pressure.
Bill

Whats wrong with front half of air box and big K&N filter clamped onto the back? Works a charm with my 29mms and will have same setup with 33mms one day. Just have to Zip tie the battery in its box to stop movenent. And you still have the standard stacks that are inside the airbox as standard

[hampshirehog]

Just to toss this in. Loads of old Brit bikes are still running around with bellmouths only and I know of loads with massive mileages and still on the original bore. I've run Jap bikes on the road with them as well - maybe not for big mileages admittedly but never had any wear issues.

Just beware of plug fouling on old strokers (the plug spanner in the tool kit was cheaper than a filter on a Bantam) and occasional issues with heavy crosswinds.

[sharpy]

Right On Bro! Your set up has everything: velocity, torque and filtration. I like the carb vent hoses too, or are those crankcase vents?
It was only by tilting the engine way forward that Yamaha was able to add an intake scoop and raise air box pressure.
Bill

Noooooo thats the fuels line and nice flowing paper filter. Sorry. And to add info aswell when i rebuilt my engine from a mistake it was running just stacks for under 2000klms and had to redo the valve seats because of pitting. CLEAN roads where ridden on but thats why i say no stacks even with mesh caps.

[Agemax]

how much should i increase the main jet size, going from pods to stacks, bearing in mind i already have a DJ stage 3 kit fitted?

[hampshirehog]

how much should i increase the main jet size, going from pods to stacks, bearing in mind i already have a DJ stage 3 kit fitted?

As you might guess......it depends. One of the functions of bellmouths is to collect and reuse fuel mixture that has bounced back off the closing inlet valves. Pods should incorporate something similar in their internals, though cheaper ones often don't. Therefor, depending on your current pods you may need to go 'downwards' on your jetting and still gain power.

However, and this is me guessing, if she's running fine on DJ 3 chances are she'll be close on bellmouths.

[Agemax]

As you might guess......it depends. One of the functions of bellmouths is to collect and reuse fuel mixture that has bounced back off the closing inlet valves. Pods should incorporate something similar in their internals, though cheaper ones often don't. Therefor, depending on your current pods you may need to go 'downwards' on your jetting and still gain power.

However, and this is me guessing, if she's running fine on DJ 3 chances are she'll be close on bellmouths.

cheers, wally. they are genuine K&N pods

[Agemax]

yoshimura power!