630 airbox mod

[DYNOBOB]

It's always bugged me when I service the air filter that it's generally clean everywhere except for the area right under the intake hole. Because the filter presses up against this opening, it gets clogged quick and has to hurt airflow.

I first tried a large washer on a 1" spacer to hold the filter back but it wasn't enough so I bent some stainless strap and made a standoff that spans the whole opening. I left the dirty filter in and have put ~300 miles on since. You can tell that air is flowing down to the rest of the filter now and the difference when free-revving the motor is obvious.

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[Huskymicky818]

It's always bugged me when I service the air filter that it's generally clean everywhere except for the area right under the intake hole. Because the filter presses up against this opening, it gets clogged quick and has to hurt airflow.

I first tried a large washer on a 1" spacer to hold the filter back but it wasn't enough so I bent some stainless strap and made a standoff that spans the whole opening. I left the dirty filter in and have put ~300 miles on since. You can tell that air is flowing down to the rest of the filter now and the difference when free-revving the motor is obvious.

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That seems so simple..... THANX for thinking of it for those of us who care enough about our bikes to do stuff like that, but are too lazy to come up with the initial design of it lol....

 

[RDTCU]

Hacking a bunch of extra holes in the airbox works too, if you're not doing a lot of water crossings.

 

[JonXX]

A buddy did this with his 630 lid

 

[Borgschulze]

Just might have to do that on my 610... semi-worried about what affect it will have in the rain though.

On my DRZ I got caught in a rain storm.. instead of 200km out of the tank before hitting reserve... I got 130km including reserve and ran out of gas before I could get to a station.

The DRZ air intake is under the seat... when I got the bike to the gas station I pulled the seat to check if the airbox was wet... and it wasn't.

 

[JonXX]

It had no effect on it in the rain.

 

[SilverBullet]

The EHS pre-filter ups the air flow considerably and is waterproof to boot. Bought my bike brand new but it already had the snorkel removed. Once I switched to a single exhaust the air box opening would get a direct input of mud from the rear wheel since no big exhaust to block it. So I bought a new air box lid and kept the snorkel but installed the EHS.

_

 

[WickedWill]

Layed and doing a bit of research.
Nice mod Bob
Here's another way to get more surface across the filter

http://www.cafehusky.com/threads/getting-more-out-of-your-630-air-filter.35884/

 

[SimpleOne]

Good ideas gents, thanks for info.

Has anyone tried, is it worth doing a mod like Bob's if you already have an EHS installed?
I just want to make sure I have the intake and exhaust sides sorted before I take this thing down to the dyno early next year....not a lot of point getting the dyno done if I'm going to come along later and change something

Cheers

 

[DYNOBOB]

just my two cents... I do to much of this ^^^ It's not worth even a couple hp to remove the snorkel or mod the airbox in a way that might let water in easier. Stakes are too high...

Just serviced my filter today, this is what it looked like after 2800 miles off-road. I'm happy with the results of the mod. I think it would have been a solid mud pie behind the snorkel w/o the standoffs.

Behind the filter, the box looks clean but the screen looks a little dusty...? Not sure if that's normal?

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[WickedWill]

just my two cents... I do to much of this ^^^ It's not worth even a couple hp to remove the snorkel or mod the airbox in a way that might let water in easier. Stakes are too high...

Just serviced my filter today, this is what it looked like after 2800 miles off-road. I'm happy with the results of the mod. I think it would have been a solid mud pie behind the snorkel w/o the standoffs.



Behind the filter, the box looks clean but the screen looks a little dusty...? Not sure if that's normal?

.

Agree with you on water and keeping it high and dry
There is a bit of discussion in this thread re the dust on screen
http://www.cafehusky.com/threads/pos-air-filter-do-your-maintenance.33340/

I have had this dust on screen too.Have changed to uni filter which has a pre filter under the main,sounds a bit back to front.Done few thousand on it and will pull it soon and inspect.
If it prevails i think the joisey mod might be next or complete silicon in

 

[Fast1]

If you take a paper towel and wipe the inside of the intake tube from the back side of the screen to where it mates with the fuel injection unit you will know how happy your engine is...

I'm with you Bob, about leaving the snorkel in place. In fact from my testing I wouldn't even take a chance with installing the EHS airbox cover mod unless you are 100% sure you will never see anymore than 6" of water. There is just not enough performance improvement for the risk. You would be better off ensuring the fuel metering is set correctly than altering the airbox on the 630 for dirt use. Sumo use is another story.

I'm also a firm believer on using only Twin Air air filter oil. The "no toil" water soluble products will not be applied to any of my air filters.

 

[mjskier]

I'm also a firm believer on using only Twin Air air filter oil. The "no toil" water soluble products will not be applied to any of my air filters.

+1 for the Twin Air filters. But I have a counter example for the "no NotOil" part.

I have been using Notoil exclusively on 2 bikes for the last 10+ years. A cfr450r MX bike and a ktm 30 xc-w trail bike.
Never had any issue with filter or ingesting stuff. And some of the hare scrambles I have run had sections with extremely fine dust.
The filter was caked on the outside, but nothing got through.
The crf450 is extremely sensitive to dust since it has titanium valves. Any dust passing through compromises the coating of these valves and result in having to re-shim very frequently. Mine hadn't moved when I did a top end at 120 hours.
Notoil is soluble in water only when you use the appropriate cleaner. Without it, the water beads up.

That being said, I'm pretty anal about my bikes and clean the filter after every ride. I wouldn't do that if I couldn't clean the filter in the sink.

 

[Fast1]

My point about the "no toil (notoil)" filter oil was based on personal experience. When/If the filter does get wet, say in a deep water crossing, the water will easily wash any dirt contained on the filter right through the filter and into the engine. This results because the "no toil" filter oil is intended to easily wash off with just water. This can also happen during intense down pours where moisture can find its way into the airbox and on to a dirt covered air filter. Just my experiences..


My 08 TE510 had over 8000 miles on it before I sold the bike and I never had to adjust the valve lash due to wear.

Like you, I'm extremely anal about air filter cleanliness and the type of air filter along with filter oil used. It is NOT convenient to use a non-water soluble filter oil but it is one task I won't sacrifice.

 

[DYNOBOB]

I don't have enough experience with dirtbikes to offer much more than this... Since I got in dual sports in 2011 I've used NoToil only because that's what one of the experienced guys I knew recommended. I respect your experience for sure Mike, but from cleaning my filter a couple days ago I can say for sure that water alone won't do anything for cleaning the filter or getting the oil off your hands! Even FastOrange didn't get the oily feel off my hands. The NoToil cleaner mixed in warm water almost instantly dissolves the oil off the filter though. I dunno...? Maybe next time I'll try TwinAir oil, surely can't go wrong with that.

I thought about pulling the airbox and checking the intake tube but that looks like some work, I don't think you can remove just the screen can you?

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[mjskier]

Even FastOrange didn't get the oily feel off my hands. The NoToil cleaner mixed in warm water almost instantly dissolves the oil off the filter though. I dunno...?

Some people have found that oxiclean will do the same job as the noToil cleaner.
Not sure if it is the sodium percarbonate or hydrogen peroxide (or both) component of oxiclean that works.

Other people have complained that noToil was dissolving the glue on their filters. True for cheaply made filters, but not an issue on twinair or the noToil branded filters.

I think filter oil fits in the same category as oil in general: You can debate to no end, and present anecdotal report for or against any brand.
In the end, it is your bike, and you have to feel comfortable with what you use.
That doesn't mean we can't ride together

 

[Spice Weasel]

I use Rock oil factory foam filter oil, its nice n sticky and blue so i can see i get total coverage.
But i am a pavement pounding supermoto rider, no trail dirt for me.

 

[SimpleOne]

Thanks gents. I might consider getting a new air box cover without the EHS, some testing has shown that whilst its 'water resistant', it's definitely not waterproof. Given how low it ends up being located as well, I don't think that is worth the risk off road.

 

[Fast1]

Something to keep in mind when evaluating your air filter, air filter oil and preserving the internals of the engine from external particles.

REMEMBER,, the engine is a huge air pump. It is essentially like a high power vacuum cleaner running and attempting to pull what ever it can through the air filter and into the engine.

When the air filter becomes wet, the engine will pull the water through the filter and into the engine. Anything that the water (fine particles) can bring with it will go into the engine.

Pull the air filter cover and filter off sometime and run the bike on a stand to feel the amount and force of air moving through the screen at half throttle. Twist up to WOT and get an idea of the CFM that will move through the opening.

If the air filter becomes dry and the air filter oil becomes less tacky.. that vacuum pump will have an easier time at drawing dust into the engine. Filter oil that looses the "tackiness" becomes more prone to allowing dust into the engine. At times it may be wise to just replace the filter with a freshly oiled (tacky) filter even if the filter does not appear all that dirty since the filter oil has lost its tackiness and stick.

Concentrating the air pump draw into a smaller surface area (such as behind the opening of the snorkel) only increases the force of draw. Bob's concept spreads that flow out which is an excellent idea.

I've been using the EHS air box lid since 2003 on other off-road toys and provided that insight to this forum for the 630 based on the inferior design of the air box cover. The EHS lid definitely allows a larger CFM flow and provides a more direct approach to moving more air than the inferior designed snorkel. Whether it is worth the risk for the extra performance is all relative to your ride environment.

The snorkel is a good design to impede water intrusion however I feel it should have a much larger opening at the attachment point to the air box cover. In stock configuration the opening is too small and concentrates all air flow to one small section of the filter which makes the effectiveness of the air filter oil and filter all that much more important.

 

[mjskier]

Good points Fast1.
Also, it depends where you ride. I don't make it an habit to cross rivers deep enough to cover the airbox.
I have seen much better riders than myself ending up taking a bath in a fast flowing river that was maybe 20" deep.
Without seeing the bottom, one rock is all it takes to tip you over. At that point, even the snorkel isn't going to save your engine from ingesting water.