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IronMan Frame differences Expert and Master

It has been regarded for a many years that the Ironman frames were all exactly the same. Well guess what, with careful review of the frames between the Master and Expert differences were noted. and with a post on the website it was confirmed that the US spec models followed the differences noted below.

The bikes used in the original findings are a 1987 Expert 60cm and a 1987 Master in 62cm. this was confirmed by forum users for 1988 and 1989 the only other years of the Expert and Master models were offered.

Master Model Expert Model
Seat Binder Bolt lug. major difference is how the seat binder bolt is shrouded in the stay on the master but exposed on the Expert

The Seat lug seems to be the most of the differences of the two models.

1. Tubing taper from the Seat stay tubing is at a different angle between the two. the capped angle of the seat stay is shallower causing a longer but more gradual angle of the Seatstay caps to the Seat lug on the Master. you can also see it in the above picture. although not easily seen.

2. Seat lug on the top where the seat post is inserted has a point on the top where on the expert it does not have the point in the seat lug.

3. for lack of better terms the sharpness of the Lugs to the tubing. you can note that the Expert has a longer point on the lugs sitting on the tubing than the Master has.

As previously noted above the sharpness of the lug work on the tubing.