'67 Atlas Air filter Assembly - info please

andyd

andyd

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Good day all. Rebuilding a '67 Atlas and need help with the air filter. Bike has concentrics and I located a filter assembly that looks like it is for the concentric. I assumed the mount plate fitted over the carb body and was held by a commando type screw on ring but the plate will not fit over the carb body. How should the air filter be mounted to the carbs?
Assume there is also a sealing ring on the filter to carb mount?
Also have a pleated pape '67 Atlas Air filter Assembly - info pleaser air filter element but I think it '67 Atlas Air filter Assembly - info pleasecannot fit in between the perforated parts of the filter assembly. It is the same width as the filter body.
Any pics appreciated.
 
Unless you are really interested in a "correct" restoration I'd check out the K&N filter Colorado Norton Works sell for the for the cNw estart equipped Commandos. Somewhere along the line I managed to pick two narrow K&N's, one is new and the other used. The new one is on my 65 Atlas and fits great, the second one I will probably put on my Commando which I just put the estart on. The width on mine is about 1-3/4" at the filter end and I can only assume this is what cNw is selling for the estarts. I tried to fit the stock air filter on my Atlas and gave up, besides the stock element would only stock ciggie butts!
Dave
 
I have a couple of kn's for the commandos that would fit, but going for original, which was why I bought the air cleaner on ebay. But must be something missing somewhere.
 
andyd said:
Good day all. Rebuilding a '67 Atlas and need help with the air filter. Bike has concentrics and I located a filter assembly that looks like it is for the concentric. I assumed the mount plate fitted over the carb body and was held by a commando type screw on ring but the plate will not fit over the carb body. How should the air filter be mounted to the carbs?
Assume there is also a sealing ring on the filter to carb mount?
Also have a pleated papeView attachment 85450r air filter element but I think it View attachment 85451cannot fit in between the perforated parts of the filter assembly. It is the same width as the filter body.
Any pics appreciated.
Click to expand...
I have a similar filter for my 650ss and although not fitted yet I believe the smaller plate in your photos goes onto the carbs before the bellmouths and is actually clamped in place by the bellmouths.
The filter body is then held to that plate by the two screws.
Cheers
 
'67 Atlas Air filter Assembly - info please'67 Atlas Air filter Assembly - info pleaseThis is my rat bike, rebuilt but no rust removed! It is mostly original. Carb plate goes on first then the threaded rings that hold plate to carbs. There is a thick black Oring, I used a thick yellow as seen in pics, between carb plate and filter housing. My filter has nothing more then window screen, no paper element.
 
robs ss said:
have a similar filter for my 650ss and although not fitted yet I believe the smaller plate in your photos goes onto the carbs before the bellmouths and is actually clamped in place by the bellmouths.
The filter body is then held to that plate by the two screws.
Click to expand...
Ok all is clear. It looks like my assembly is for a smaller carb - maybe the 28mm carb has a smaller body. I can use part of a Commando inlet bellow for the sealing o-ring that fits on the air filter rear.
 
mean gene said:
View attachment 85458View attachment 85460This is my rat bike, rebuilt but no rust removed! It is mostly original. Carb plate goes on first then the threaded rings that hold plate to carbs. There is a thick black Oring, I used a thick yellow as seen in pics, between carb plate and filter housing. My filter has nothing more then window screen, no paper element.
Click to expand...
Thanks for the pics, appreciated.
 
andyd said:
Ok all is clear. It looks like my assembly is for a smaller carb - maybe the 28mm carb has a smaller body. I can use part of a Commando inlet bellow for the sealing o-ring that fits on the air filter rear.
Click to expand...
If you want that look then it's possible to enlarge the holes to suit
I have a friend who did just that for his Atlas.
I like @mean gene 's idea of the o-ring sealer. I'm pretty sure the originals had an air leak there.
 
robs ss said:
If you want that look then it's possible to enlarge the holes to suit
I have a friend who did just that for his Atlas.
I like @mean gene 's idea of the o-ring sealer. I'm pretty sure the originals had an air leak there.
Click to expand...
You have a repop filter housing. It does not have the original "holder" for the pleated filter. I will post pics of entire assembly later. You will have to rig something up with a piece of foam filter cut to fit. The order of assembly is: (1) mounting plate with two holes over carbs; (2)threaded rings on carbs to hold plate; (3) filter body over carb mouths. Should be rubber ring shaped liners on the entry holes to filter body to seal into carbs. Filter body then mounted to mounting plate with threaded studs welded to filter body that pass through holes on mounting plate. Use nuts to draw filter body towards mounting plate and then the rubber rings seal everything together. I will post pics later.
 
andyd said:
Good day all. Rebuilding a '67 Atlas and need help with the air filter. Bike has concentrics and I located a filter assembly that looks like it is for the concentric. I assumed the mount plate fitted over the carb body and was held by a commando type screw on ring but the plate will not fit over the carb body. How should the air filter be mounted to the carbs?
Click to expand...
Your s/h air filter housing may be for the Amal Monobloc carbs which were fitted on the Atlas 1962-1966 (p/n 030337) It seems you are missing the side walls? The correct filter body for Concentric carbs is available from Norvil (p/n 033030).

- Knut
 
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I hope this is helpful. The first picture shows the interior of an original filter assembly. The crennelated (?) mesh behind the perforated metal holds the pleated paper in place. The rubber grommet (I called it a ring in my original post) seals the filter assembly to the carbs when all is bolted up. The bracket shown in the picture to the right is held on to the carbs by rings that thread on to the outside of the carb mouths. Norvil used to stock the rings but is out now. I suspect thathat the rings and grommets may be used on Commandos but I'm not an expert on modern (joking) bikes.
 

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Bodger said:
I hope this is helpful. The first picture shows the interior of an original filter assembly. The crennelated (?) mesh behind the perforated metal holds the pleated paper in place. The rubber grommet (I called it a ring in my original post) seals the filter assembly to the carbs when all is bolted up. The bracket shown in the picture to the right is held on to the carbs by rings that thread on to the outside of the carb mouths. Norvil used to stock the rings but is out now. I suspect thathat the rings and grommets may be used on Commandos but I'm not an expert on modern (joking) bikes.
Click to expand...
Certainly is.
I am now sure the filter assy I have is for a monoblock bike with smaller body carbs than the 30 mm concentrics. I can cut up old commando inlet bellows to mount on the body for the rubber grommet and enlarge the plate mount holes to fit the now 32m carbs and use a commando ring to attach the plate to the carbs. I will also add inner spacer tubes on the through bolts to stop deforming the end plates and seal the end plates probably with black silicon.
All sort of simple, but not as simple as the K&N option thats for sure - but if you want original that's the price you pay!
Thanks everyone.
 
andyd said:
Certainly is.
I am now sure the filter assy I have is for a monoblock bike with smaller body carbs than the 30 mm concentrics. I can cut up old commando inlet bellows to mount on the body for the rubber grommet and enlarge the plate mount holes to fit the now 32m carbs and use a commando ring to attach the plate to the carbs. I will also add inner spacer tubes on the through bolts to stop deforming the end plates and seal the end plates probably with black silicon.
All sort of simple, but not as simple as the K&N option thats for sure - but if you want original that's the price you pay!
Thanks everyone.
Click to expand...
One thing is certain - the distance between carb centres will be the same - so, if you're willing to "fettle" you'll get it to fit.
Cheers
 
Don't know if someone says that the spacers between carb and head are different from concentric (thin) and monobloc (thick ) ??
 
Over the years a good friend has made absolutely correct Atlas/650SS air filters for all the large British bike supply companies: CNW, British Cycle, etc. He is willing to make one offs for a reasonable price. If you are interested, and serious, let me know and I will pass along his contact info.
 
Stephen Hill said:
Over the years a good friend has made absolutely correct Atlas/650SS air filters for all the large British bike supply companies: CNW, British Cycle, etc. He is willing to make one offs for a reasonable price. If you are interested, and serious, let me know and I will pass along his contact info.
Click to expand...
I assume Colin Kelly?
But I now have the unit found on Ebay that will be fine after a bit of work.
 
I have found its easy to cut a piece of Uni filter media to sandwich in between the outer and inner portion of the housing. This filters very well and didn’t appear to cause any restriction issues
 

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Ive also made a hammer form to make new copies of the endplates- if anyone needs a set let me know.
 

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