Classtime 

I've read anywhere from ounces to 60 %. But how does that work? For example, what if my trailer and cargo weigh 50 lbs. what would be the ideal weight on the tongue?

gsa103

Enough that if the weight shifts slightly it wouldn't make the rear wheel lift. For most cars its about 10% of the load.

fietsbob

Consensus ?

Classtime 

I assumed it has been discussed and there is some "best practice" regarding tongue weight that didn't turn up in my searches.

CliffordK

You need some weight.

With cars, with negative tongue weight, your car will fishtail, and I believe the same happens with bikes.

On the flip side, a car can only carry so much weight until the rear wheels sag. Sway bars can help some. Most hitches and trailers will have a listed tongue weight limit.

With the bike, some might depend on your bike connection to the trailer. If you have a rigid connection, then you can add a fair amount of weight. A coil spring for the connection, and your weight is limited.

For your hypothetical 50 pound bike trailer, I'd probably target 10 pounds or so of tongue weight, but could go anywhere from a pound or two up to 20 pounds or so.

Classtime 

Some recommendations for MOTORCYCLES pulling trailers range from 10-20% of gross trailer weight with most leaning toward 10%. Surly, on the other hand, suggests ballancing the load over the trailer axle. (Resulting in 0%?)

Tongue weight's effect on braking seems most significant. With more tongue weight, braking causes the trailer to dive and consequently unweight the front wheel. With negative tongue weight, braking would unweight the rear wheel. Zero tongue weight probably contributes to some vertical oscillating while just riding along.

Rowan

The weight on the tow hitch has more to do with how well the rear wheel of the bike behaves, which then translates into how the bike handles, especially under brakes.

10-20% sounds appropriate, but more weight than less, in my opinion, is better. I don't agree with Surly at all on this. While yes, it is correct to balance the weight over the rear axle, some of it does need to be forward to ensure that the trailer doesn't start wagging the rear of the bike. The last thing you want is for the trailer to jack-knife on the bike.

I have drawn quite a few trailers -- a large one that has carried things such as sofas, and smaller ones both in two-wheel and single-wheel form. In *all* cases, I ensured that the weight was up around 10lbs when mounting on the bike. Well, almost all cases... the one time was when the rear end played up going downhill.

BBassett

Part of the equation has to be the type trailer and total overall weight of it loaded. I carry around 100 lbs. in mine and have shifted the weight around to see how it feels a few different times. I like to concentrate the mass and physical size closer to the trailer wheel. Good luck and happy rides.

CliffordK

In a sense, your Bob-Style trailer might act more like a 5th wheel than a bumper-hitch trailer.

Although, most bike trailers do attach at the rear axle, or in front of the axle.

Reynolds 

On my 2 wheel trailer, I don't think it's critical, as long as there is some weight on the tow arm.