Ok, I've been meaning to post this for a while. I hope it proves helpful
Tioga MX-402 Sealed HeadsetBy all accounts it looks pretty much identical to the Tange 303 / 320 etc but there are some subtle differences and an unusual sealing system. As far as I've been able to find, this is a unique Tange Seiki made, chromed steel headset that only came Tioga branded and in this type of box.
The main things to look out for are:
i) The top nut has an integral hard rubber cap with raised text saying - Water Resistant - Japan - Tioga. It also has an O-Ring underneath.
ii) Both cups have grooves in the base to hold rubberised / sealed washers.
iii) The shape of the adjusting cup is a bit wider and flatter than the 303 / 320 (to accommodate the sealed washer).
I've seen these come up for sale, often with the sealed washers missing. I've also seen one with an O-Ring Crown Race (320 type) which I guess could work with the grooved cup but I couldn't say for sure. That one still left the adjusting cup unsealed so probably had mis-matched parts. I've done a like for like comparison with mine and one Martin has so I'm happy the set up in the pics is stock and as it should be.
Big thanks to Martin (and his dad) for taking the time to send me pics and to Mick and Warren who carefully reproduced the decals for me. Anyone wanting these decals could email Waza: waza@waza.net
