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Can i drill a hole in my swingarm?

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7.1K views 6 replies 5 participants last post by  DCO  
#1 ·
i want to hide my rear brake line by runing it through the swingarm, i would need to drill a small 1/2" hole for this then it would come out where the shock is, i think it would look real clean.can it crack around the hole?would i need to re enforce it by welding around the hole or something?
 
#2 ·
i wouldn't suggest it.....

i can't say for certain, but drilling could compromise the structural integrity of the swingarm and could lead to a crack or worse. the handling of the bike is highly dependent on the rigidity of the swingarm, so best case scenario would be a feeling of instability while cornering.

i think they are made from powdered aluminum, which is a bitch to weld properly. have to have the right welder and some special compound




again, this is JMO....
 
#3 ·
Having worked in an aluminum foundry once upon a time as a quality assurance inspector, you'd DEFINITELY reduce the structural integrity of the swing arm by drilling a hole in it. These days they are vacuum drawn & lost foam mold cast to rather tight tolerances allowing for minimal material yet good structural rigidity. A hole will deform that very quickly and develop cracks as stresses attempt to go around the new hole and welding does require some specialized equipment to do properly, as well as some skill. Welding the cracks isn't very doable as the heat from the weld only weakens the surrounding area even more, with more cracks showing up later. The powered aluminum alloy once cast is heat treated to give it certain strength characteristics that the welding undoes.

Stay away from the drilling and welding, the danger isn't worth it.. You could go with some stainless steel Galfer lines and dress it up nice. They even have some colored ones.
 
#5 ·
On the other hand I know of dozens of guys that have drilled their swingarms to mount spools(on bikes that didn't have spool provisions: F2, F3, F4, F4I, Katana, etc...) and had no problems at all. Granted they were drilling 6mm holes and not 1/2". I am sure the larger the hole, the greater the possibility of structural failure.