I started working on some bike projects in preparation for the eventual arrival of spring. I started by removing the front exhaust pipe to correct a loose header pipe. I then decided to clean the air filter so I proceeded to remove it and I immediately noticed cracks at two of the mounting stud locations.

I then decided to remove the backing plate to confirm my fears. As you can see in the photos, two of the mounting tabs had broken completely free from the rest of the plate.

So the first question is - what would cause this to happen?

Secondly, does anyone know where I can pick up a plate at a reasonable price? I called Arlen Ness and was given the part #18-584 for the aluminum part and #18-594 for the black.

 

I just tool my A/N big sucker 2 off my Street Bob today. I don't know if the back plate will work but if it will you can get mine.

 

Thanks for the offer, but I checked and it won't fit.

 

Anyone have any theories on why the plate would break in this manner?

 

maybe not torqued correct ? maybe factory defect ? cant be sure , maybe to tight ?
replacements ---- ps dont forget a new gasket!!!!!
http://www.cruisercustomizing.com/ar...part/AN-18-594
or a list of them all here
http://motorcycle-accessories.cruise...search2.y=-212

 

I don't have one on my bike, but you might want to do a search on here. I seem to remember this showing up before. Not sure what folks did to resolve it. Good luck.

 

https://www.hdforums.com/forum/sport...cked-help.html
check this thread alot did call or email
call / email where u got it from or arlen ness they will replace it from what iv read

 

Arlen Ness made in China junk.

 

BUT the same thing happened to me as I was installing mine, I emailed AN and got a reply, sent me a new one with gasket for free!! (Torgue per spec when installing) They are aware of the problem and did good on it. Send pics, yours look exactly like mine. Checked my email, fellows name is Marco (marco@arlenness.com) ! Nice guy at AN.


Wow-EH

 

I have some Twin Cam ones laying around, no Sporty ones though.

It happens, it is cast aluminum. Happens with the HD SE ones too. Poor casting combined with inherent vibration of the engine. Does not happen to every one of them, but it is not uncommon.