I am planning an extended cycling tour in rural part of China on my tadpole trike, pulling a trailer with my trike, and bringing 2 German Shepherd dogs with me.
Since the ride will be over mountaineous region ranging from 6,000 feet to 15,000 feet, the dogs would be helping to pull during ascend, which I suspect could be as bad as 1:3 and enjoy the ride on the trailer during descend.
I bought a Robin EH025 25cc engine today to convert the trike to power assisted, the 25cc engine is to comply with China's law for power assisted HPV which has to be less than 30cc.
When the dogs are too tired to be pulling on ascend they will be sitting on the trailer. Our combined weight with luggages would probably be around 180kg, approx. 400 lbs.
The trike is presently fitted with a 3 x 8 speed cartridge hub, and I intend to swop it to the Rohloff internal gear hub that is on my mountain bike now.
QUESTIONS:
1: What would be the optimal gear ratio for the Robin EH025 engine, probably running between 5,000 to 6,000 optimal rpm to be pulling a load of 400 lbs up the ascend with a gradient of 1:3, at whatever attainable speed.
2. What would be the optimal gear ratio for the Robin EH025 engine to be cruising on reasonably flat terrain with a load of 400 lbs, at whatever maximum attainable speed. I do not need to have quick acceleration, I would pedal to overcome the inertia, I just need the engine to do the job of cruising comfortably when both human and dogs are too tired to pedal towards the end of the day.
3. With the gear ratios decided, I would prefer a system that I can switch quickly when the trike is stationery, between low gear for ascending and high gear for cruising.
I thought about friction drive and I can get a local machine shop to custom make a simple one that I can swap quickly between a bigger roller for speed and a smaller roller for ascend. However, one of the problems with the friction drive is that it doesn't work very well with knobbly tire, but I will need the knobbly tire, or at least semi-slick/knobbly for the terrain that I will be going through. Some of them would be just muddy terrain without asphalt, would it slip when they are wet and muddy? not to mention the amount of mud churn up by the tire that would stuck in the friction system.
4. That leaves chain drive, I guessed the popular choices are Gebe and Staton. The Gebe does not allow me to change between 2 gear ratios, so it is out. The Staton, whilst it does not work like a 2-speed gearbox, I hope to use it as a reduction gear box, and considering the extended drive chain on the trike, my thoughts is to have the engine/gearbox mounted within the drive train and in that way I could also utilize the rear cassette/rohloff internal hub to achieve the multiple gear ratios for ascend/cruising.
At present it is very much just thoughts and I am hoping to learn from those who have gone on these paths before deciding on the final solution.
Thanks.
Since the ride will be over mountaineous region ranging from 6,000 feet to 15,000 feet, the dogs would be helping to pull during ascend, which I suspect could be as bad as 1:3 and enjoy the ride on the trailer during descend.
I bought a Robin EH025 25cc engine today to convert the trike to power assisted, the 25cc engine is to comply with China's law for power assisted HPV which has to be less than 30cc.
When the dogs are too tired to be pulling on ascend they will be sitting on the trailer. Our combined weight with luggages would probably be around 180kg, approx. 400 lbs.
The trike is presently fitted with a 3 x 8 speed cartridge hub, and I intend to swop it to the Rohloff internal gear hub that is on my mountain bike now.
QUESTIONS:
1: What would be the optimal gear ratio for the Robin EH025 engine, probably running between 5,000 to 6,000 optimal rpm to be pulling a load of 400 lbs up the ascend with a gradient of 1:3, at whatever attainable speed.
2. What would be the optimal gear ratio for the Robin EH025 engine to be cruising on reasonably flat terrain with a load of 400 lbs, at whatever maximum attainable speed. I do not need to have quick acceleration, I would pedal to overcome the inertia, I just need the engine to do the job of cruising comfortably when both human and dogs are too tired to pedal towards the end of the day.
3. With the gear ratios decided, I would prefer a system that I can switch quickly when the trike is stationery, between low gear for ascending and high gear for cruising.
I thought about friction drive and I can get a local machine shop to custom make a simple one that I can swap quickly between a bigger roller for speed and a smaller roller for ascend. However, one of the problems with the friction drive is that it doesn't work very well with knobbly tire, but I will need the knobbly tire, or at least semi-slick/knobbly for the terrain that I will be going through. Some of them would be just muddy terrain without asphalt, would it slip when they are wet and muddy? not to mention the amount of mud churn up by the tire that would stuck in the friction system.
4. That leaves chain drive, I guessed the popular choices are Gebe and Staton. The Gebe does not allow me to change between 2 gear ratios, so it is out. The Staton, whilst it does not work like a 2-speed gearbox, I hope to use it as a reduction gear box, and considering the extended drive chain on the trike, my thoughts is to have the engine/gearbox mounted within the drive train and in that way I could also utilize the rear cassette/rohloff internal hub to achieve the multiple gear ratios for ascend/cruising.
At present it is very much just thoughts and I am hoping to learn from those who have gone on these paths before deciding on the final solution.
Thanks.
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