Undertankfilter

[TOMCAT]

Please explain .. have you run that on your bike yet ?? Did you make it or have it done , looks interesting.

 

[barbagris]

Just a pipercross PK003F clamped on the grey bit. There is also a K&N option

Ran like this for two years - before you sent me another plenum to butcher

 

[TOMCAT]

So you weren't happy with that set-up , obviously. Do you have any pics of it on the bike. Assuming you'd need to modify a bearclaw or did you run it without the claw. Struggling to imagine how it would look bolted up. Did that setup not do away/lessen the induction noise ??

 

[barbagris]

So you weren't happy with that set-up , obviously. Do you have any pics of it on the bike. Assuming you'd need to modify a bearclaw or did you run it without the claw. Struggling to imagine how it would look bolted up. Did that setup not do away/lessen the induction noise ??

Quite the reverse - was perfectly happy and the modified plenum thing was really a sort of R&D experiment to see if the OEM bellmouths improve over triple K&N's (which imo they do). As a sort of precursor to Batterseas bespoke 1-pce idea that started with Pipercross and migrated to RAMAIR. There is a part of me that simply wont do things because everybody else does.

The modified plenum is louder - but not NASTY. Makes me think that a well made 1-pce could be perfectly acceptable (as those with 1-pce Pipercross's and cut claws have suggested). No it wont be as quiet as stock - but will make servicing easier.

The undertank was no louder than stock. Some appreciable benefit in breathing but not MASSES better. But it'd run quite happily at 200kph and higher. In fact my first major concern after fitting the PCV and it started to sort fuelling out was the alarming ease with which I was regularly exceeding the "lock you away and throw away the key" limit. More than enough air.

Indicated 230kph is the highest I've risked - and only once - I like my licence too much.

Triple K&Ns have one major saving grace imo. They allow easy access to the throttle body balance screws.

Not yet sure what I'll do - If the RAIMAIR 1-Pce appears soon - I'll try that. If it's too loud - then I'll probably go back to the under-tank if I'm honest.

The filter nestles between the frame rails and wiring at the rear of the tank. Very neat. Totally invisible. No piccies - sorry. Those grey bits are the stock plenums - The claw fits with no issues at all. The filter is on the inner box that's hidden away under the tank.

 

[dougl]

This was one of the early Rocket mods. Rather than messing with the plenum itself you can put a big K&N on the end of the rubber hose from the plenum. This doesn't accomplish much - just avoids the seat ducting.

 

[barbagris]

This was one of the early Rocket mods. Rather than messing with the plenum itself you can put a big K&N on the end of the rubber hose from the plenum. This doesn't accomplish much - just avoids the seat ducting.

tbh - I have to admit I'm not a big fan of K&N's. Most foam filters seem to flow better.

Be good if somebody with a K&N tried a Pipercross (or other foam).

DITCH THE RUBBER HOSE ENTIRELY!

I did it to free up the box under the seat really.

 

[Power-Tripp]

Please don't take this as urinating in your Wheaties, but as something to be aware.

This style of intake is pulling hot air off the engine, after it has passed through the hot radiator. This can mean that intake temps can be 150°F or more.

Each 7.4°F of temperature increase results in a 1% drop in air density, and a corresponding drop in output. This means that on a hot Summer day where ambient temps are in the 90°F range, you can be losing 8% or more of output.

For instance, running three K&N RU-2780 air filters under the bearclaw, and then testing with the Bearclaw removed, results in a 3.7% difference in output with many full exhaust systems I have tested. Pulling all air from under the tank will result in a greater difference.

While this may not matter much to some, it is something others may be concerned about. This is why I bring it up.

 

[dougl]

Please don't take this as urinating in your Wheaties, but as something to be aware.

This style of intake is pulling hot air off the engine, after it has passed through the hot radiator. This can mean that intake temps can be 150°F or more.

Each 7.4°F of temperature increase results in a 1% drop in air density, and a corresponding drop in output. This means that on a hot Summer day where ambient temps are in the 90°F range, you can be losing 8% or more of output.

For instance, running three K&N RU-2780 air filters under the bearclaw, and then testing with the Bearclaw removed, results in a 3.7% difference in output with many full exhaust systems I have tested. Pulling all air from under the tank will result in a greater difference.

While this may not matter much to some, it is something others may be concerned about. This is why I bring it up.

Does this mean that pulling air through the seat duct is better than a Corbin with no duct?

 

[Power-Tripp]

Yes. But only by a small amount.

 

[barbagris]

Please don't take this as urinating in your Wheaties, but as something to be aware.

This style of intake is pulling hot air off the engine, after it has passed through the hot radiator. This can mean that intake temps can be 150°F or more.

Each 7.4°F of temperature increase results in a 1% drop in air density, and a corresponding drop in output. This means that on a hot Summer day where ambient temps are in the 90°F range, you can be losing 8% or more of output.

For instance, running three K&N RU-2780 air filters under the bearclaw, and then testing with the Bearclaw removed, results in a 3.7% difference in output with many full exhaust systems I have tested. Pulling all air from under the tank will result in a greater difference.

While this may not matter much to some, it is something others may be concerned about. This is why I bring it up.

This is something I'm pondering upon at the moment. Good input - thank you.

At 3000rpm I'm (as do we all) drawing in 57.5litres a second (ish) - and it takes a mass of heat to warm that volume of air. I'd not considered the radiator flow I confess.

I really need to get a temp sensor under there and see what the real temp is under there compared with external sensor. You've just helped me justify (to me) a gauge - Thanks!