Adding a bike rack when using a dolly? "The physics don't allow it"?

[NXR]

I agree with both of you on that aspect. And heck, the weight of the ebikes will help hold the toad rear end down, right?

I can see a complication with putting 170 lbs of ebikes and rack on a car being towed on a dolly due to the angle of a car on a dolly. It's nothing unlike going up or down a hill but that bending force would be there 100% of the time instead of intermittently.

I'll try to remember to put a digital level on my car when we load it in two weeks. It would be an interesting if useless fact.

Ray

[Alpine36]

We just put the bike rack in the receiver on the rear of the toad.
BTW, did you know some bike racks are approved for RV use and some are not? This was news to me. Bought ours at ETrailer, Reese brand rated for four bikes, 160lbs? and its RV apporoved. Under $100 delivered to the front door. We're happy with it, although we only carry two "old school" pedal bikes. Really a stout unit. I'm confident it would hold up to two EBikes no problem, especially with additional ratchet strap or two. If weight is a concern just remove the batteries if possible.

[NXR]

Originally Posted by trampsrv

sell the dolly you dont need and buy the dolly you do need(tandem-tow dolly) before your ebikes fall off of your bike rack and kills somebody on the interstate!!

Since we don't have any ebikes, I'm thinking that is not a problem.

Ray

[twinboat]

Originally Posted by NXR

I agree with both of you on that aspect. And heck, the weight of the ebikes will help hold the toad rear end down, right?

I can see a complication with putting 170 lbs of ebikes and rack on a car being towed on a dolly due to the angle of a car on a dolly. It's nothing unlike going up or down a hill but that bending force would be there 100% of the time instead of intermittently.

I'll try to remember to put a digital level on my car when we load it in two weeks. It would be an interesting if useless fact.

Ray

I calculated mine at 7°.

I V cut the 2" to 1 1/5" hitch adaptor, bent it to 7°, and welded it back together.

Now the rack is level when the pickup is on the dolly.

[Alpine36]

Originally Posted by twinboat

I calculated mine at 7°.

I V cut the 2" to 1 1/5" hitch adaptor, bent it to 7°, and welded it back together.

Now the rack is level when the pickup is on the dolly.

Good idea. One thing to note, at least on the Reese bike rack, it swings down by removing a single hitch pin. It could easily be modified to swing up 7* to level with a little welding creativity.

[NXR]

From the superb technical support dept at RoadMaster:

Not sure of a specific article. Flat towing any vehicle has virtually no tongue weight Since it is just being pulled. Towing any type of trailer including a tow dolly does have tongue weight that has to due with the weight of the trailer pushing downward on your receiver. The tongue weight depends on the weight of the trailer and the vehicle on it.

So it's tongue weight apparently. I responded with:

Yup, that’s where I’m getting confused. The 077-8 has a 400 lb tongue weight limitation. The tow dolly with the car loaded imparts about 180 lbs of tongue weight at its normal height if my digital bathroom scale is anywhere near accurate.

The bikes and rack would add another 170 lbs for a total of 350 lbs or 12% below the 077-8 limitation. That is approaching my “nervousness limit” because I like 20% margin but at least it’s not 5%.

Since you mentioned tongue weight, one issue might be that the 077-8 adds 10” to the 5,000 lb hitch which is rated at 500 lbs tongue weight, so there is some lever action there. Maybe that is what could exceed the 5,000 lb hitch tongue rating.

RoadMaster responded with:

So if your trailer is 180 and bike rack is 170 so you have 350lbs of tongue weight and when you go over a hill or bump the tongue weight is double depending on the steepness of that hill. If it is a hill with a large curve then the tongue weight is dramatically increased.

I replied with:

I’d think that the dynamic loads are factored into the design of the hitch when the limitations are set, kind of like how tire pressure is always specified in “cold” pound when the hot pressures can be significantly higher.

I won’t bother you anymore and your assistance is building a stronger case for moving to a flat tow. Because my wife really wants ebikes.

And they finalized with:

Factoring the dynamic loads in does sound like a great idea, not sure why it isn't done. Ebikes sound awesome! I hope you guys get them! If you have any further questions or concerns please do not hesitate to call or email back.

Simply superb support for a product inquiry on a hundred-dollar part, eh? Or it's a really slow day in RoadMaster Land.

Ray

[twojayhawks]

Originally Posted by NXR

Since we don't have any ebikes, I'm thinking that is not a problem.

Ray

If you haven't already purchased you may shop some more. 61 lbs sounds very heavy to me. Heavy to load/unload as well as ride. Ours are 40 lbs ea.

[Rockwood27]

I had a Winnebago Class A that required a 10 inch drop to dolly or flat tow. I also wanted a bike rack on the back of the MH. I ended up welding a second receiver tube to the bottom of the existing hitch receiver tube. The new tube was used for the dolly/towbar ball mount. The upper, original tube for the bike rack. The new tube dropped the hitch mount by about 2.5 inches, so an 8 inch ball mount worked.

I am a Facebook forum member of the RadPower ebike group. The most common bike rack that I see for twin 60+ lb. ebikes is from Hollywood Racks. You may want to check them out.

[NXR]

Originally Posted by twojayhawks

If you haven't already purchased you may shop some more. 61 lbs sounds very heavy to me. Heavy to load/unload as well as ride. Ours are 40 lbs ea.

It is. 61 lbs without the battery. 51 lbs with the front tire removed.

We've found a wide variety of lighter ones but they are either seriously underpowered (36 volt motor and 36 volt 5.2 AH battery on 16" tires) or they are not step-through.

Due to my wife's back problems she cannot swing a leg over the center bar.

If yours are step-through and not underpowered, would you please share what they are?

Ray

[NXR]

Originally Posted by Rockwood27

I had a Winnebago Class A that required a 10 inch drop to dolly or flat tow. I also wanted a bike rack on the back of the MH. I ended up welding a second receiver tube to the bottom of the existing hitch receiver tube. The new tube was used for the dolly/towbar ball mount. The upper, original tube for the bike rack. The new tube dropped the hitch mount by about 2.5 inches, so an 8 inch ball mount worked.

I am a Facebook forum member of the RadPower ebike group. The most common bike rack that I see for twin 60+ lb. ebikes is from Hollywood Racks. You may want to check them out.

I've looked at those racks but they do not have the ramp to push the bikes up and down.

Do you have a 5,000 lb hitch? That's another limiting issue for me.

Ray

[vettenuts]

Originally Posted by TXiceman

I think you will find the bouncing on the rear of a motorhome is much worse that that on the rear of vehicle like a car or SUV. The auto suspension is much softer on a auto than a motorhome as well as the distance from the pivot point (rear axle) is much shorter on the auto,



I do not buy that assessment.



Ken

I was going to post the same thought. They have bike racks specifically rated for Motorhomes, which are a stronger design.

I have the same duel tow bar from Roadmaster and when I called them they told me that I could dolly tow with it, as long as I didn’t exceed tongue weight. My dolly only had about 40-50 lbs of tongue weight and I towed with that setup for many thousands of miles.

After reading all the conflicting responses from the manufacturers, I just see a lot of CYA. I had my bikes on my dolly towed car hitch mounted bike rack, but I made a special adapter to account for the tow angle since the front tires were off the ground on a dolly.

[Rockwood27]

I no longer have the Winnebago, but it did have a 5K/500 lb hitch. The Winnebago was on a Workhorse 22K/26K chassis. You won't overload the hitch. The TowMaster dolly barely added 100 lbs tongue weight. Overall, I was at 21.8K/25.4K GVW/GCW on the chassis.

Originally Posted by NXR

I've looked at those racks but they do not have the ramp to push the bikes up and down.

Do you have a 5,000 lb hitch? That's another limiting issue for me.

Ray

[Rockwood27]

How about a small motorcycle rack like this.

https://www.prolineracks.com/item/B-...rrier-Ramp-752

[Rockwood27]

Have you looked at RadPower ebikes.

https://www.radpowerbikes.com/

They have 3 or 4 step through models. The motor is 750 watts and the battery is 48V/14AH. They sell for $1.5, including free delivery. Personally, I'm planning on getting the RadCity step through. It weighs 65 lbs with battery.