Eh??  That's all over my head I'm afraid   What's a sedis chain?  I guess a brand of chain??  As for saddle, that's not a big problem.

Out of curiosity, for an average to maybe half-way decent-ish MTB (eg my Specialized HardRock) going at 30 mph on average MTB tyres on the road, would a roadbike be significantly faster for the same power input???  I'm sure I can go faster than I do on mine - 16.4 mph average on the way to work today (half of it on a loooong uphill haul) can be bettered I'm sure - even with full inflation I'm sure I'm losing a lot in the tyres...

I guess next stop = road-only tyres (I never take the bike off-road)....