P
prism
Guest
I currently have a suitable bicycle, as well as a) machine-tools; b) experience with engines, motorcycles, and related things; and c) some real questions, some of which might sound weird.
1) I am currently thinking of going rack-mount friction drive using a four-stroke motor. I've heard how these setups tend to devour tires and slip in inclement weather, and I just might have a partial solution. It involves two rollers pivoting such that both rollers contact the tire at 'ninety degrees', with the rollers being roughly 1.6 inches outside diameter and coated with grit of some kind. (aluminum oxide, silicon carbide, others.) The central shaft drives both rollers using #25 chain, and in turn is driven from the engine clutch using the same type of chain. (I'm working on the drawings still)
Question: do I need to have my head examined?
2) While I do not mind the smoke, smell, and noise of two-stroke motors, I strongly suspect discretion is advisable in my case - hence the use of a four-stroke. I'm leaning toward the Honda GX35, though I've read about the Subaru Robin eoh35.
Question1: is the Subaru Robin a 'better' (term used loosely) engine?
Question 2: I've heard my share of weed-cutters, backpack blowers, Go-Peds, motorized skateboards (long years ago) and related engines. I've not yet heard either of the two engines mentioned previously. Are they significantly quieter, or is the chief difference the tonal quality of the engine noise compared to say, uh, a Zenoah or Tanaka? I'm prepared to assemble a large-volume muffler if needed - and should I do so, I can just hear the comments:
"What is that thing there?" (points to muffler)
"The muffler. Why?"
"I've never seen an engine that small with a muffler that big..."
3) My goal is to manage groceries and related shopping on a semi-regular basis, and longer trips (possibly hundreds of miles) now and then. Currently, I need to lose a great deal of weight (enough that I'm embarrassed to say how much), I've had surgery on both knees (they complain if I ride any real distance), and I wish to avoid undesireable attention (chiefly from constables). Also, I will commonly be towing a trailer (one of which I already have; I hope to make another.)
Question: I'm planning on gearing the thing such that normal 'cruising' speed is in the ten to twelve miles an hour range. (i.e. 5,000 rpm or so; both engines have their torque peaks in that region.) I've seen signs locally describing distances and 'nominal' times for bicycles, and that speed range seems to fit. (It's also nearly double what I can pedal for any distance).
Am I crazy? I know these setups are capable of higher speeds, but I do not feel comfortable traveling at twenty-plus on a bicycle. (Besides, I'm not a teenager any more - top of ten gears, a slight downgrade, chain singing, and clocked at 50+)
Thanks in advance for your consideration
1) I am currently thinking of going rack-mount friction drive using a four-stroke motor. I've heard how these setups tend to devour tires and slip in inclement weather, and I just might have a partial solution. It involves two rollers pivoting such that both rollers contact the tire at 'ninety degrees', with the rollers being roughly 1.6 inches outside diameter and coated with grit of some kind. (aluminum oxide, silicon carbide, others.) The central shaft drives both rollers using #25 chain, and in turn is driven from the engine clutch using the same type of chain. (I'm working on the drawings still)
Question: do I need to have my head examined?
2) While I do not mind the smoke, smell, and noise of two-stroke motors, I strongly suspect discretion is advisable in my case - hence the use of a four-stroke. I'm leaning toward the Honda GX35, though I've read about the Subaru Robin eoh35.
Question1: is the Subaru Robin a 'better' (term used loosely) engine?
Question 2: I've heard my share of weed-cutters, backpack blowers, Go-Peds, motorized skateboards (long years ago) and related engines. I've not yet heard either of the two engines mentioned previously. Are they significantly quieter, or is the chief difference the tonal quality of the engine noise compared to say, uh, a Zenoah or Tanaka? I'm prepared to assemble a large-volume muffler if needed - and should I do so, I can just hear the comments:
"What is that thing there?" (points to muffler)
"The muffler. Why?"
"I've never seen an engine that small with a muffler that big..."
3) My goal is to manage groceries and related shopping on a semi-regular basis, and longer trips (possibly hundreds of miles) now and then. Currently, I need to lose a great deal of weight (enough that I'm embarrassed to say how much), I've had surgery on both knees (they complain if I ride any real distance), and I wish to avoid undesireable attention (chiefly from constables). Also, I will commonly be towing a trailer (one of which I already have; I hope to make another.)
Question: I'm planning on gearing the thing such that normal 'cruising' speed is in the ten to twelve miles an hour range. (i.e. 5,000 rpm or so; both engines have their torque peaks in that region.) I've seen signs locally describing distances and 'nominal' times for bicycles, and that speed range seems to fit. (It's also nearly double what I can pedal for any distance).
Am I crazy? I know these setups are capable of higher speeds, but I do not feel comfortable traveling at twenty-plus on a bicycle. (Besides, I'm not a teenager any more - top of ten gears, a slight downgrade, chain singing, and clocked at 50+)
Thanks in advance for your consideration