I have a 99 Road king and I am curious about how the weight of a rider and or passenger affects the final belt drive tension.

The shop manual says to check the deflection in the belt with the weight of the rider so my question is ...

Does the belt tend to get tighter or looser when the bike is fully loaded and the suspension compresses ?

 

Intuitively I would say that the belt tightens as the suspension is loaded, I don't know for sure.

 

you have to think about the fulcrum of the swingarm arch. Yes it tightens, that's why you are to adjust with a rider or equivalent weight on the bike.

 

My manual gives two measurments - one on the Jiffy stand and one with the rear wheel suspended? Doesn't talk about the rider being on the bike. It's a factory shop manual - 2005 RK Classic.

 

lots of posts on drive belt tension adjustment made with driver on bike. the manual i looked at says on jiffy stand and only 1/4 to 5/16 play at 10 lbs pressure, this is what i did and seems like belt is way to tight. have high whinning noise when decelerating in 3rd, 2nd gear. Lots of posts mention 3/8 to 1/2 inch but some say with driver on bike which makes a big difference in the adjustment. whats the correct way??? I have a 2000 road king. thanks for any help

 

When I adjust the belt after a tire change, the bike is suspended vertically in the lift, no rider, full weight of the bike on the tire. Adjusting to the spec in the manual always results in a belt too tight. I adjust to 1/2" using my finger as a guide and an occasional double check with the gauge shows 1/2" @ 10 ft.lbs.
The belt will tighten with rider/pass/luggage but shouldn't be overly tight if adjusted as above. If you still hear the whine you can loosen the adjustment to see if it makes a positive difference and if so then you know where your belt needs to be when adjusted properly.