Re: Fitting a springer fork to a short head tube?
I went through this trying to fit a suspension fork to my wife's mountain bike that had a 4" long head tube. I couldn't find anybody that could cut the threads further down the steering tube to allow it to fit my wife's ATB. I found a suspension fork that allowed you to change the steering tube. I ordered a short Marzocchi steering tube from EBay and it all worked good.
I don't think you will find a springer fork with an interchangeable head tube. You will likely need to have your steering tube cut, shortened and rewelded.
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