Stuff like that you soon learn though - in that situation you should already be in the right gear for the speed approaching the roundabout i.e. braking/slowing down for the roundabout you change down as you approach, into 2nd if you have to slow and wait for any cars, and if it's clear, away you go. If you have to stop, down another into 1st. A lot of it is planning ahead, which soon comes with experience. I've never had a gear indicator and never had an issue not being in the right gear.
Without a gear indicator, you just have to keep the bike in the right revs. slow a bit, revs drop to 3k, change down. slow some more, revs drop to 2500, down another gear. If you have to stop, down another gear and 9 times out of 10 you'll magically be in 1st.
I know all of that.
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Just saying it can be difficult for a learner to pick up when it's their first time on a 650cc bike
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