CRF70 DIY Airbox

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GooseMan

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Kangarilla, South Australia
I was really getting tired of getting water in my carby and the filter getting choaked in mud so I had a crack at making my own air box and though I'd share it with everyone, its pretty rough but it does the job and won't cost you a fortune.

To start off I found some down pipe which I think is about 80mm in diameter and cut it the same length as the foam air filter. Then I drilled many holes in it like below with a 10mm splade bit. This will slide over my filter. (note some pics were taken before the holes were drilled.
7533453148_acbf9152a1_z.jpg


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The screws will be explained in a moment. I then found a larger piece of down pipe about 100mm in diameter to slide over the smaller one and cut it about 40mm longer then the last.
7533440096_037bdaa297_z.jpg

The screws simply hold it central inside the larger pipe.
7533440920_a0a601dabc_z.jpg

A end cap was then put over the end of the 100mm pipe.
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The inside piece will slide in with about 20mms of space between it and the end cap of the white pipe to allow maximum air flow through the filter. It was then painted and fixed behind the rear shock using these things.
7533439102_eef6edca95_z.jpg

they were screwed into the pipe and then clipped onto the subframe. The hard part was finding some tube to connect it to the carby, I managed to find one which is fuel resistant and could bend just enough with out kinking. Hose clamps were used at each end of the tube to hold it in place but they are not in the pictures.
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And to top it off it is hard to see it underneath and it actually works.
 
yeah im gonna find some rubber on the weekend to go under there.
and beats paying $15+ for something like this too
*WATERPROOF AIR FILTER 38mm* 125cc PIT PRO MOTOVERT PIT BIKE THUMPSTER ATOMIK | eBay
That looks a bit restrictive aswell.
 
Gonna finsh this off with some info, this will not work on the 160ho, 155z, any daytona 150 or larger. This is because these engines require more air flow and this air box does not allow enough flow. Anything smaaller though and it will work fine. hope that helps people.
 
Hmmmm I just got a ycf airbox from tassy Stu...so won't work on the 160?

Sent from my WT19i using Tapatalk
 
Ah no worries cheers guys! I just noticed this thread today! Its a bit crazy even with a bit of mud on the weekend the air filter on the perimeter frame Foxico hardly got a spot of mud on it....I think tyres and rear shock in the mud are my real problems...need to make up one of those guards like my67xr has asap!

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Yeah I made one for mine, you can use a fender off this bike I have, I think it has two?, which reminds me I was gonna drop that off tomorrow wasn't I, I shall put it in the car now.
 
doing great mate, got his cast of today and his finger is healing really well. The plastics nurse was amazed at how well he is healing actually :) back in two weeks to get the rod pulled out and then physio so all in all he is doing great, but we are exhausted. 2 hr trip to the hospital, 4 hrs in the hospital and then 2 hrs back, amazing how something that requires no physical activity can leave you so dead....
 
doing great mate, got his cast of today and his finger is healing really well. The plastics nurse was amazed at how well he is healing actually :) back in two weeks to get the rod pulled out and then physio so all in all he is doing great, but we are exhausted. 2 hr trip to the hospital, 4 hrs in the hospital and then 2 hrs back, amazing how something that requires no physical activity can leave you so dead....


Awesome that he is healing up well!! People often discount emotional stress but its a real factor and its really really draining, and driving for 2hrs is pretty exhausting by itself...especially with the weather you're probably getting that came through up north SA Friday night...massive cold front...
 

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