Installing a CPR air filter on my 990

[Desmofan]

Originally Posted by -GUV-

I rotated the rubber intake sleeves 180deg as they aren't very well port matched, no more noise.

Could you elaborate on "rubber intake sleeves rotated"? I installed the CPR on my 990SMT (secondary flies out, Wings, TuneEcu 7/21/12 "kevtx" map).

I had assumed the whistling at cracked throttle was just throttle body/butterfly noise now unmuffled?

[-GUV-]

The rubber sleeves that hold the throttle bodys to the heads.

[-GUV-]

A tip for adventure owners, while you have the throttle bodys off flip the securing rings (screw heads face right side) so that you only have take the right side tank off to remove them in the future if needed.

[dad2bike]

Originally Posted by -GUV-

A tip for adventure owners, while you have the throttle bodys off flip the securing rings (screw heads face right side) so that you only have take the right side tank off to remove them in the future if needed.

On my carbs I was able to flip and point them so I can reach in with a small handle screwdriver and remove the carbs with both tanks still installed. Only have to remove the glovebox & seat. I bet you can do the same with the TB's. Take a close look.

[olec]

Hi!

I will order one of these CPR filters but have a couple of Q's:

- Anyone tried those prefilters and do you feel the more restricted air-flow?
- That breather hose, Maybe a stupid question, but do you have to route it to the inside? Why not just filter it on the outside and just leave that mess out.

Thanks!

[Johnf3]

Originally Posted by olec

Hi!

I will order one of these CPR filters but have a couple of Q's:

- Anyone tried those prefilters and do you feel the more restricted air-flow?
- That breather hose, Maybe a stupid question, but do you have to route it to the inside? Why not just filter it on the outside and just leave that mess out.

Thanks!

If you do that, call CPR before you order and get them to send you a plate without the mounting hole for the breather. That is what I did. The one way valve that is in line with the breather hose should eliminate the need for an actual crankcase filter, but it is a safe idea to fit one just in case.

[olec]

Any cons besides of taking care of eventually oil spill 'somewhere' rerouted?

[Johnf3]

Originally Posted by olec

Any cons besides of taking care of eventually oil spill 'somewhere' rerouted?

No issue for me. Never had any oil out of it.

[Spark01]

Originally Posted by moto-treks

Mine had only the one near the temp sensor. My 2nd valve motor didn't contact the base plate but the idle motor did ever so slightly.

The extra pockets in the base plate didn't help (maybe a small life time extension) i replaced the base plate last week just in case and found cracks on both side at the D-zus back plates.
And i had the same problem as you with the temp sensor(holes to big and no screws delivered).
Lucky i have a small collection of stainless steel bolts in my garage

But i don't like the new routing of the crank case breather, as i still have the 2nd valve motor inplace.
The hose is pushing against the front injector connector and the connectors of the 2nd valve motor.
So i removed the hose and sealled the hole with a bolt and 2 washer with some rubber seallant inbetween.
And ordered a small crankcase breather filter to put on the hose.

i think this also will help for lowering the intake temp some degrees. because the warm fumes from the crankcase will no longer enter in the airfilter.

[olec]

Originally Posted by Spark01

The extra pockets in the base plate didn't help (maybe a small life time extension) i replaced the base plate last week just in case and found cracks on both side at the D-zus back plates.
And i had the same problem as you with the temp sensor(holes to big and no screws delivered).
Lucky i have a small collection of stainless steel bolts in my garage

But i don't like the new routing of the crank case breather, as i still have the 2nd valve motor inplace.
The hose is pushing against the front injector connector and the connectors of the 2nd valve motor.
So i removed the hose and sealled the hole with a bolt and 2 washer with some rubber seallant inbetween.
And ordered a small crankcase breather filter to put on the hose.

i think this also will help for lowering the intake temp some degrees. because the warm fumes from the crankcase will no longer enter in the airfilter.

So you made an extra pocket on the old baseplate, but it didn't help (too much), and you reaplaced it with the updated baseplate now and then you found more cracks in the old one when removing it? (just to be sure before I order it that there are no more issues with the new one)

[MAXVERT]

Originally Posted by olec

Hi!

I will order one of these CPR filters but have a couple of Q's:

- Anyone tried those prefilters and do you feel the more restricted air-flow?
- That breather hose, Maybe a stupid question, but do you have to route it to the inside? Why not just filter it on the outside and just leave that mess out.

Thanks!

I've installed the red prefilter, oiled with NoToil.
It's a porous foam and I didn't notice any change in
noise/performance.

'07 990 A Remus 2 to 1 Akro map CPR filter with prefilter.
NoToil

I didn't know about the new plate without a hole for the oil breather
tube so on mine I filled in the hole with JB Weld.
I've always rerouted the breather to out side the air box
on the five LC8's I've owned.

Max

[Sporting Wood]

Originally Posted by moto-treks

Just wondering, whats the reason for attaching the hose to the inside to route the crankcase vent directly over a throttle body?

[Johnf3]

Originally Posted by Sporting Wood

Just wondering, whats the reason for attaching the hose to the inside to route the crankcase vent directly over a throttle body?

That's the poor man's supercharger, with the added bonus of hot, oily crankcase vapors. No better place for it then directly down the throat of the carb. Kidding aside, lots of bikes, KTM's real dirt bikes w/ FCR carbs, for example, have their crankcase vent hoses attatched directly to the carb manifold. It works fine. In the case of the CPR set up shown in the picture, my preference was a bit of a cleaner less homemade look, so I just left it outside.

[moto-treks]

Originally Posted by Sporting Wood

Just wondering, whats the reason for attaching the hose to the inside to route the crankcase vent directly over a throttle body?

The stock configuration has the breather vented inside the air box so I'm guessing this is done so that reason. I'm sure it has something to do with EPA requirements too.

You can have the breather vented; 1) outside, 2) inside with hole directing the vapors to the intake or 3) inside with no hose. I thought I'd try inside with hose first. I may remove the hose and see what it looks like after a few hundred miles.

[Sporting Wood]

Originally Posted by Johnf3

That's the poor man's supercharger, with the added bonus of hot, oily crankcase vapors. No better place for it then directly down the throat of the carb. Kidding aside, lots of bikes, KTM's real dirt bikes w/ FCR carbs, for example, have their crankcase vent hoses attatched directly to the carb manifold. It works fine. In the case of the CPR set up shown in the picture, my preference was a bit of a cleaner less homemade look, so I just left it outside.

I get the sarcasm... There was some in my original post too.

I've built a bunch of race bikes, changed everything except for the air in the tires, and I've never ran the crankcase vent into the airbox. More often, I've ran it down to just above the countershaft so any hot oily water vapor lands on the chain doing it some good, or simply putting a high mounted filter on it to keep the critters and water crossings out... been known to just stuff some filter foam inside the tube and zip tie it to the frame.

Originally Posted by moto-treks

The stock configuration has the breather vented inside the air box so I'm guessing this is done so that reason. I'm sure it has something to do with EPA requirements too.

You can have the breather vented; 1) outside, 2) inside with hole directing the vapors to the intake or 3) inside with no hose. I thought I'd try inside with hose first. I may remove the hose and see what it looks like after a few hundred miles.

Correct, EPA. I'd at least dump the hose on the plate. Should you blow a water pump, these LC8's are known to chug that tasty looking chocolate milkshake mixture of emulsified oil, water and antifreeze up that hose... and right into your throttle body... which would make the whole thing suck much worse.