cut and welding a stock arm to make it a 240 arm

[nabusa]

I've had two 240 arms now one from roaring toys and some no name one I got on cl. Both had a hint of offset on the wheel so a 1/4" custom sprocket needs to be use which cost $100. Now I myself have always wonder why do they not make it offset to the right a 1/4" so you can use your stock sprocket not to mention so you don't have to grind your frame?

Hayabusa 250 Wide Tire Swingarm Kit | eBay

In this link this guy had his stock swingarm cut and looks like they added 2"s of material to fit the 240 wheel. Using his setup, he uses the stock front sprocket plus he doesn't have to notch his frame. So my question is one is his arm safe? And why aren't 240 swingarms built so it is offset to the right so you don't have to use the 1/4" sprocket and notch the frame?

 

[m_ridgeway]

The tire will be way offset to the right side and look like hell without the offset sprocket and grinding the frame. If the tire is mostly centered up without the offset sprocket it will hit the chain on the wheel

 

[Fastfrog007]

^what he said