Is the vehicles transmission downshifting to a lower gear as you go uphill? If not, that would be your first place to look. After that I would suspect that your engine timing is not autmatically advancing as it should be.
Gravity.
downshift
the tilting of the bike causes the floats in the carburator to rise wich cuts off the fuel intake
It requires extra power to go uphill, against the pull of gravity.
Going uphill takes more power than going on the flat, so unless you can add more power, you have to trade some speed for power to be able to go uphill.
check the air intake
Because it doesn't have enough power to pull itself. All vehicles slow down uphill if you don't feed them more fuel.
Generally when we are going up hill because of the gravity pull, more power is needed. So when traveling uphill more power is needed than downhill.
It loses power because going uphill is harder then going downhill therefore causing it to use more gas and then making it lose power bit by bit.
cool
If it is an automatic transmission going uphill it will downshift to a lower gear for more torque.
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