I've done it before. It'll be fine as long as you're not taking the headers on and off very often, and you're careful when you do. One of the main reasons for studs is to save wearing the threads in your (very expensive, alloy) cylinder head.

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I spent a lot of money on travel and racing motorcycles - the rest I just squandered.

XT660Z - Commuter, Adventurer...Racer?

www.dashmoto.net

Other bikes >> MT-03 / CG125BR-J / ER-6F
Departed >> ZXR400L3 / EC300 / DR-Z400E / DR800S / GPZ500S / GS400