Here you can find my unique retractable motorbike carrier project with 38 photos and detailed explanations...
Step 1: Old One!
When we bought our motorhome, it already equipped with a "carrier" on it.
Design of this carrier was really terrible:
- Due to straight main beams, it reduces departure angle of RV and crashes to ground even at small slopes; for example every ferry travel :(
- Lenghtens RV approximately 55cm, permanently
- Can carry only a motorbike (small one :) ) and no space for our bicycle
- Masks licence plate (it is not legal of course) and no extra driving lights
- No place for bike ramp and we had to carry it in cargo space!
- Main rail steel was too thin and flimsy
- Heavy for its size due to unnecessary thickness of stainless steel pipes
Of course removed it after our second trip and start to design much better one by myself; hooray! :))
Step 2: New Design :)
I called customer relations deparment of my motorhome company in Germany and learned that its chasis construction is designed around 150kg including carrier itself.
Planning to design a carrier which can capable to carry motorbike + bicycle + generator + ramp.
My motorbike is around 100kg, carrier itself calculated as (preliminary designs) 32kg...
Have enough capacity for bicycle (12kg) :))
Sometimes I'm using Honda EU 10i generator (12kg) to run 220V air conditioner while travelling.
Fully loaded, slightly exceeding approved capacity; will not tell to anybody ;)
RV schematic is not my own; it is here just to give an idea about calculation basic.
After CAD design, prepared main parts by plywood and check if they interfere with RV's body...
Step 3: Preparing / Finding Parts
Main arms made of 8.0mm thick steel, rail and ramp 4.0mm embossed aluminum sheet and generator rack and bicycle rail 3.0mm aluminum sheet.
All sheet parts laser cut and bended in local company.
Note that connection cut for ramp and mounting "lug" for bicycle extension slide...
Running lights are all led, made by Farba :)
Licence plate lights are Hella, chromed.
Also we need steel tubes for fixing mechanism and horizontal support connections.
All screws are stainless steel.
Step 4: Temporary Installation
Here you can see how it works:
We have two main "arms" fixed to motorhome chasis with two bolts each.
Triangular secondary arms are retractable and turns at pivot point on top of them.
These arms are holding loading ramp and extensible small arms to hold bicycle rail also.
Loading ramp fixing its special space by a wing nut only.
Behind of the main rail, there is a small aluminum plate to hold my Honda Eu 10i generator. It is fixing here by strap.
Bicycle rail "opens" by stainless steel hinges when in use. If you are carrying only a motorbike, extensions can stay inside and rail "closed".
When not in use, whole caririer retracts onto RV body and running light + licence plate holder turns to backside.
Step 5: Final Installation
Removed everything off and sent steel parts to electro galvanising.
Led lightings mounted and wired.
All parts are ready for final installation :)
Here you can see retracted position and fully loaded carrier together.
Looks very good and professional :))
Step 6: Testing and Finishing
Step by step loading photos here.
- Only generator,
- Generator and motorbike,
- Generator, motorbike and bicycle loaded and fixed.
Note that stainless steel "eyelets" to fix motorcycle by ratchet strap. I'm using two straps for extra security.
Bottom eyelet has 120mm lenght steel cylindiric rod to distribute load...
I'm using bicycle eccentiric clamps to fix light plate to desired position.
All project costs to me around 250 USD in materials.
Again, value of the success is: Priceless :))