Has anyone replaced the air filter housing with a pod filter?
 

I'm a heavy guy and I have a knobby on the rear wheel, which means the tire bottoms out on the airbox. I'm wondering if I can't fix this by removing the airbox and replacing it with a UNI foam "pod" filter. Has anyone attempted this before?

Would it reduce or increase the intake noise that reverbs between the rider and the windshield?

Charles.

I assume you've already maxed out your pre-load on the rear shock?

Yup. It's fine for the street, but not so much for off-road.

Charles.

I have no experience with this particular bike but plenty of others and of cone filter conversions; intake noise is the least of your problems as it will totally throw off your fueling. It CAN be made to work but expect a lot of fiddling with your carb settings, needle positioning, main and idle jetting changes etc

No need for any of that with the RX3, since it's fuel injected.

I have the same problem as you charlie, that's why I ordered this shock and will see if it will come on, because I don't see any other solution.

Dang it of course, that's what you get for trying to be smart :doh: just have had such bad luck with pod filters I wanna stomp and jump on any that I see

The only issue I can see ... where is the air temp sensor located..
they are usually in the air box... relocating it somewhere else may
not give a correct reading of the intake air temp...

.

This is not the only problem, because the air box is connected to the crank pulley, also any reduction in air flow will weaken the bike (I know, because I tested), but the worst may be the noise, and the original box can be lined with rubber in the middle and make a slalom for air or put a mesh, such as it is in db killer to the muffler and it is quiet for this reason it is not worth replacing it you need to lift the suspension and do it right the shock absorber I ordered has already left Belgium and should reach me next week wait charlie only you shortened the swing arm and on the YouTube video the ukrainian did the same and when he put longer shock the spring rubbed against the engine and he had to return to the original swing arm size.

Seems like the easiest solution would be a shorter rear tire or slightly longer shock. If you go the shock route it can still be a gamble because a new shock might be 10mm longer, but have a 10mm longer stroke (some aftermarket shocks have more stroke than the stock ones) so you're back to the tire hitting the air box.

Yes it is, but if on the original shock it rubs against the air box, it will not change anything, remember that originally this bike has a rear wheel size 15 then changed to 17, after changing the shock you will probably need to lengthen the side stand.

Yep that's why a shorter tire would be easiest, but a slightly longer shock (compressed) is also a possibility... and you're right, that could require a longer stand and maybe longer legs too. Lol

The tire will not give much, because maybe 1 cm, and the motorcycle on the original shock absorber rubs with 1 Charlie, and I would like to take a passenger, and it comes out 1.5 Charlie, so changing the tire is a half-measure that will fail with a higher load.So you have to be prepared for different possibilities.

You're right, I didn't realize that those bikes came with such a narrow range of tire diameters. My tbr7 with the odd 17" rear tires have tires available in several sizes with several diameters, with a couple inches difference in heights. My bad.

So, the reason I'm doing this is because I did raise the rear suspension. I cut 6mm out of each dogbone and welded them back together. This gave me about 0.75" raise in the rear, which is a finger's width from bottoming on anything. I can get a finger between the upper fender and tire, and when the wheel is all the way forward in the adustment it's still not touching the airbox. This is with a 130/80/17 Kenda Big Block tire. When running a golden boy/SR244 in 5.10x17 the tire still rubs the fender but now misses the airbox (though it's VERY close). I did have to weld an extension on my side stand.

However, with the rear lifted this much the bike is VERY unstable at 70+mph. It has a dangerous wobble. I tried sliding the forks down in the trees as much as I could, but this only made it slightly better. The bike is also a lot taller and I am less confident when the trail gets nasty.

So, my aim here is to return the bike to the stock height (I've already bought the parts from CSC) and remove the airbox instead. My other option would be to buy the 19" front wheel and run a slightly-oversized 3.50x19 front tire. But that's quite a bit more expensive than going back to stock and throwing on a foam uni filter. A lot more work tho, that airbox doesn't look like it's coming out easily.

Charles.

I deleted the airbox on my Hawk and threw a cheapy Amazon pod filter on it. The Hawk is a horse of a different hue, though. It's a carb, and dead simple. There's no electrics to worry about for IAT, or anything like that. Just a few minutes with a dremel tool and off the old airbox came. I would say go back to stock height, and call CSC and see if they know of a stiffer rear shock that will keep you from bottoming out on the airbox. Another option you might consider is getting some fiberglass mat and cut out the bottom of the airbox where the tire hits it, and then just change the shape with the fiberglass mat. Pretty much everything that's going to be a solution is going to be a lot of work.

You can buy a complete wheel from an older version and then you can fit a 15 tire and the problem is solved, or you can just change the rim. I would go in this direction if you do not want to raise the suspension because you do not have to play with the air box

The whole point here is to run knobby tires. A 15" rim has zero selection in knobbies.

Charles.

Charlie, you keep raising the bar, so how about a 16" rim?

I'm going to experiment

That red spring is allot softer, more coils/thinner wire. Funny thing is it looks due to the much longer travel the both shocks look they'll compress to about the same length.

The new shock is a centimeter too long and I knew it would be so I had to drill additional holes higher and then it will be 410mm instead of 425mm and it will be perfect, because 405mm is minimally too short today I will try to do it the shock is firmer and damping works of course as everything in this motorcycle fits on millimeters.

it was a bit of fun

everything fits

So far I am half satisfied, because I have to ride to see how the spring works more rebounds and when I pull the bike off the center stand, the shock does not drop the bike stands normally on both stands and you sit on it normally the rear wheel is raised about 2 centimeters, because that's how much it was hanging above the ground when the bike was standing on the center stand I had to pump up the pressure in the shock absorber, because the damping was working poorly finally I will be able to take my girlfriend for a ride.

So how does it ride? You have the 18" or 19" front wheel? What's it like approaching max speed?

Charles.

I don't know Charlie World War 3 is starting and I don't really feel like riding the Russian scum invaded Ukraine and is massacring civilians.

Yeah. I get that. Nothing I can do about it though, except drive myself crazy watching the news. A ride would be far more productive for me. But then, I'm very far away in the USA. Judging by the license plates on your wall, you're somewhere in Europe, possibly Germany. That's a lot closer and I can understand why you'd be more freaked out than I am. Sorry things are going to shit over there.

Charles.

I am in Poland 50 km from my border there is fighting it's all the fault of the German project nord stream 2 now 4 reich blocks stopping the swift system and Putin goes further the materials are on crazyshit.com or sadystic. pl but it's terrible content and shows that the Russian army is a bunch of militiamen and young people in their 20s and are from far away villages in Russia they didn't know they were going to war the losses of Russians are huge they are foam scared and untrained Putin is a complete idiot, because he is living in the past he forgot that now there is internet and phones everything can be seen he is losing the war and he knows that if he does not conquer Ukraine it is his end, if Ukraine surrenders I will have to go to war because I live in the eastern flank of nato and I am 34 years old.

In general I took up another project, but it requires a lot of testing, and thus a lot of time I need to produce 8 volts from 1 candle to have energy to charge the phone in case of need, of course I could easily make a large generator, but I have set myself an ambitious plan and it has to consist of 4 Peltier modules, the one used by NASA so far it is going better and better, half of the generator produces 2.80 volts, but there are different modules and one produces 1.50 volts and the other 1.20, but it is not enough I have to give a thicker heating plate, because this one is too thin, and in other tests I got 2.30 volts from one module, which is very high.

I rode a motorcycle and the spring is too hard for me I weigh 76 kilos I will try to change it for the original, if it works it will be great, but it may be that I will have to buy a shock absorber tomorrow I will take it apart and I would have to fill the shock absorber with nitrogen, because when it gets hot the air will expand and damage the seals.

This is why I'm going to a pod filter. I have bottomed the bike three or four times since I removed my raise-up kit, and when I inspected the airbox yesterday I found it was compromised.

https://www.advrider.com/f/attachmen...8-jpg.3570977/

One half of the case is split and no longer sealing. Plus the screw threads are showing.

Raising my bike fixed the contact problem, but left me with a far more dangerous problem. At or near 70mph actual, the bike starts to wobble and weave. I first noticed a little instability in the bike after I removed the stock hard luggage and all the associated bracketry. But raising the rear definitely exacerbated that. It makes sense, the rear is over an inch taller than it would be with the 15" rim the bike was designed for. An extra .75" on top of that was too much. With the stock parts back on the bike, I'm back to the pre-wobble state, where there's just slight instability at high speed in crosswinds. And I think switching to a larger front tire will fix that.

But in the meantime, I have no airbox. The intake manifold is an odd 43mm, but 1 3/4 is just over 44mm, so I ordered a 1.75" silicone tube, an adapter, and a 1.75" foam air filter. I'm going to tuck the air filter up under the left side cover, and build a partial airbox around it using a PVC tube that's at least an inch larger in diameter than the new foam filter. I want to keep the water out as much as possible when doing creek crossings. I'm also going to extend the plastic fender under the bike with a mud flap, and put a hugger on the swingarm, all to prevent dirt from being flung forward. This is because the airbox acted as an inner fender.

I looked at the amount of work to shorten the airbox front to back, and it would have taken way too much work and time, and a glued airbox is still not going to stay airtight forever, it's no longer structurally sound no matter how much epoxy you lather over it. Plastic welding might work, but the plastic welding kit costs more than the parts I bought to build a "cold air intake" using a name-brand UNI foam filter no less.

I now have significant room under the seat, which I may convert to tool storage. (So long as I leave the 8mm socket and ratchet somewhere else. I could also maybe put a PVC storage tube under there which would be accessible from the wheel well. I'll toy around with it a bit once I have the air filter assembled (waiting on parts)

Charles.

So.... I took the airbox out, hacked it up with a rotary tool, and then used a fiberglass repair kit (resin and woven fiberglass) to cover the open area near the battery. I didn't really have to close it up, but I figured the less dirt that can get into the filter area the better. I then coated it with flex-seal to make it black and to close up any voids that the fiberglass missed.

https://www.advrider.com/f/attachmen...9-jpg.3595161/
https://www.advrider.com/f/attachmen...0-jpg.3595163/

All this cutting allows the airbox itself to sit 1.5" closer to the front of the bike. I had to make an extension bracket for the rear mount and drill two holes and mount it with some 1/2" spacers.

https://www.advrider.com/f/attachmen...6-jpg.3595203/

Finally, you can see what I've done for my air filter here:

https://www.advrider.com/f/attachmen...4-jpg.3595201/

It's a 1 3/4" hose, 1 3/4" hose coupler, and a 1 3/4" foam UNI filter, with significantly more surface area than the stock filter. You can also see my crankcase breather peeking out from its new home. It has a 12mm hose coupler connecting the hose to the breather filter. All are oiled with Jeg's air filter oil, which came dyed blue.

My suspension is at the normal level and I have no wobble, no tire contact with anything under the bike, and I can run big tires on the back with no problems now. The only detriment to this is my maximum water crossing depth has been reduced significantly.

So, why did I hack up the airbox at all? Why not just remove it? Well... I looked into modifying a hugger rear fender to fit the RX3, and I looked at using a mudflap to create a new inner fender, but when it came down to it the stock airbox forms the rear fender and if I cut it apart I'd be able to protect my new filter from road dirt from several different sides. That's why I repurposed it.

If I start going on super deep water crossings again I'll have to extend the silicone line and basically build a snorkel.

Charles.

I know the primary reason for doing this was to gain more swing room for the rear tire, but I'm curious as to how this setup sounds vs. the OEM intake. Louder or quieter? No change? The RX3 is a pretty quiet bike exhaust-wise; it's the induction noise that can get to you after a while.

I'm waiting for an 11mm spring for a new shock I think in the original air box there is very little chance of water getting in and it can be silenced, but the original exhaust isn't quiet either, because it's a full-through muffler with 1 catalytic mesh I currently have 3 db killers and maybe I'll put a 4th on the muffler elbow and I don't understand what charlie means by saying the rear of the bike floats sideways, because in my opinion that's not normal behavior.

I purchased some sound deadening material from amazon, and added it to the left side cover, the left and bottom of the seat, inside on the top of what remains of my airbox, and I also used it to seal the original air intake holes.

It's a lot quieter now. The intake noise is still there, but now I hear the muffler more than the intake. It's way, way better when climbing steep hills. Before it'd be almost deafening even with earplugs in, and now it's pretty manageable.

I have no idea what Lukas means by "floats sideways".

When I run my front tire out I'll probably upgrade to the 19" front rim, and then revisit using a longer shock or shortened dogbones.

Charles.

you wrote earlier
What do you mean by unstable?

This is what I mean. Start at 2:38.


https://youtu.be/z3OQTU-kE2s?t=158


This happens because there is not enough trail, and because I've reduced the weight of the bike significantly. The rear of the bike is lifted 1" over the design spec with a 17" tire. It's lifted even more because I'm using a knobby 80 profile tire instead of the stock 70 profile tire. Then it's lifted further because I have the shock preload set very high. Finally, I removed the side cases and racks, which resulted in the center of gravity of the bike to shift slightly, and also the rear to ride higher. Lifting the suspension even more with my dogbone modification was enough to cause the bike to develop a high speed weave right around 70mph. Going back to stock fixed it.

To make a bike more stable, you increase the trail. The easiest way to do this is by putting a larger wheel or tire on the front, to raise the front end. To make a bike turn quicker, you'd generally lower the front end by raising the fork tubes up in the trees. Lowering the front end or raising the rear gives the bike a "flickable" feeling, at the expense of high-speed stability. There is only so high you can go before the trail is too short and a high speed weave can develop.

Charles.

Damn, you got me thinking charlie the spring will be here any day now and I'm afraid to get on a motorcycle those guys in those old videos are some hardcore.From this video it appears that this behavior is influenced by lifting the rear of the motorcycle , tire and the weight of the rider and trunk one motorcycle was all built up against the wind, yet it was tossing around

Note that my weave wasn't NEARLY as bad as those, but it was unnerving. I'm going to eventually get the larger front tire and then I won't have this problem. Unless I decide to sell it first. I'm a big fat guy and I need a little more grunt.

Charles.