I'm converting an old MTB into a commuter and upgrading the fork to add suspension. I have an 18 mile each way commute and want suspension for the potholes/manholes I can't seem to avoid. The head tube measures 1 1/4 i.d. and has an existing 1 inch dia. threaded fork. I have a 1 1/8 threaded suspension fork I'd like to use instead. Is there a headset I can buy that will allow this fork to fit?