Hmmm..
What bike was the metal tank from?
How bout we turn this into a " How to " thread with plenty of pics and info.
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tank is from an 02 620. my understanding is that all FI tanks from 2001 until d/c'd are identical. the issue, as mentioned in the post above is clearance. the bottom contour of the metal tanks does not allow for clearance of battery, ecu, etc. therefore, the pan must be cut and reformed which is what this particular fitting was meant to address. i will post up more info/pics when the welder gets it back to me. as far as capacity and weight, i think i was initially gaining a few more drops of capacity in the metal tank but now with new lower pan i may very well lose it. yes, it is going to be a bit more weight but one complaint i've never had about this bike is that it was too heavy
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as long as the weight added isn't in rotating mass i don't suspect it'll be too bad. and, hell, i'd take an extra 10 lbs to get rid of this F#@$&% stock tank once and for all.
as for seat and tank fitment, the seats on all FI bikes are the same so there's no issue there. just have to fabricate a new rear tank mount bracket on the tank side as the old poly tank's doesn't line up and the original from steel tank frame bracket robs a half an inch that can't be spared.