OP, this may not be what you want to hear, but knobby tires in that size are not optimum for commuting in terms of rolling resistance (assuming you are riding on the road). If you use the bike on and off road, that is what you have to live with, if you are 95 percent road you may want to at some point look at smoother tires...... Knobby resistance can not be fixed by higher pressure
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Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)