Closest thing to a reliable 60 MPH Build

[darwin]

Wondering if anyone has ever seen an enthusiast build capable of reliably traveling 60 for long periods of time? Just curious as to how far people have taken this hobby to. Also unrelated, someone hit me yesterday with their car (more of a love tap, gotta love slip lanes....) and they bent my pedal in a bit so now it hits the frame of my bike a little and its kind of annoying. Should I bent it back and if so how or should I just replace the damn things?

You ever take a good look at a bicycle wheel bearing? Does it look to you like it's designed for 60mph? If so, go for it. Just my opinion they're not in anyway. Neither are the tires. Not talking one race here, but a daily driver you can safely rely on.

 

[jasone]

There's guys pushing 80-90mph

 

[darwin]

OK, gotta ask. What is a slip lane? Never heard that term before.

 

[Risk Man]

There's guys pushing 80-90mph

Yes, there is. Tour de France top speed is:

"Still, it’s a long way off the top speed ever recorded at Le Tour – Marcus Burghardt took that honor in 2016 with his descent of the Cote de la Comella, in which he hit a frankly terrifying 81.2 mph (130.7 km/h)"

This got me thinking that while we fret about riding a motorbike (designed for human power) at 40MPH when you read about the speed in tour races on those thin tires, I don't feel so unsafe riding over 35 mph.

 

[Sidewinder Jerry]

OK, gotta ask. What is a slip lane? Never heard that term before.

A slip lane allows you to merge into traffic at an intersection instead of having to make a right turn. Unlike merging lanes on an interstate, vehicles must yield to through traffic in a slip lane.

 

[Sidewinder Jerry]

Yes, there is. Tour de France top speed is:

"Still, it’s a long way off the top speed ever recorded at Le Tour – Marcus Burghardt took that honor in 2016 with his descent of the Cote de la Comella, in which he hit a frankly terrifying 81.2 mph (130.7 km/h)"

This got me thinking that while we fret about riding a motorbike (designed for human power) at 40MPH when you read about the speed in tour races on those thin tires, I don't feel so unsafe riding over 35 mph.

Several factors to consider here:

First, the man is a professional cyclist.

Secondly, his pedal only bicycle probably cost over $20,000 and has been designed to handle those speeds.

Last of all, gravity is the accelerating force; it's spread over the entire mass of the bicycle and rider. Unlike a motorized bicycle whose accelerating force is concentrated into a small area where the rear tire meets the traveling surface.

 

[ImpulseRocket]

Everybody is so focused on speed that they never touched on the concept.of reliability.

First, what are we defining as reliability?
Do we want it to be reliable whilst always doing 60mph? That is possible with the right engine choice, but likely not cheap. Most of these small 2 strokes are pushing at their limits, and that is generally not a good recipe for reliability.

Take the Phantom 85 as a prime example. Damien and I have the same engine and both of us ride 90% or more of the time just cruising along, never going past 30 to 35, because the engine is happy there, not being pushed more than say half-throttle. The engine can do 45 to 50mph. Others, especially on the Facebook group, claim the engines are junk because they shell crank bearings and seize the motor while trying to go everywhere at Mach 2 with the throttle pegged during break in.

Our engines are at least a year old and have a couple thousand miles-ish. They have both had a weird noise or funky issue, but have otherwise been reliable. The other guys grenade them within a couple hundred miles. One member has gone through 4 V3 engines in 2 months, but claims it's the engine being junk. He literally had a crank bearing fail in 2 days.

 

[Sidewinder Jerry]

Everybody is so focused on speed that they never touched on the concept.of reliability.

First, what are we defining as reliability?
Do we want it to be reliable whilst always doing 60mph? That is possible with the right engine choice, but likely not cheap. Most of these small 2 strokes are pushing at their limits, and that is generally not a good recipe for reliability.

Take the Phantom 85 as a prime example. Damien and I have the same engine and both of us ride 90% or more of the time just cruising along, never going past 30 to 35, because the engine is happy there, not being pushed more than say half-throttle. The engine can do 45 to 50mph. Others, especially on the Facebook group, claim the engines are junk because they shell crank bearings and seize the motor while trying to go everywhere at Mach 2 with the throttle pegged during break in.

Our engines are at least a year old and have a couple thousand miles-ish. They have both had a weird noise or funky issue, but have otherwise been reliable. The other guys grenade them within a couple hundred miles. One member has gone through 4 V3 engines in 2 months, but claims it's the engine being junk. He literally had a crank bearing fail in 2 days.

I've got a Honda GXH 50 engine that's been on the shelf for 10 years now. I said I was going to put it on my Staton Inc gearbox when the Robin Subaru 35 wore out.

I've decided next year I'm going to put the Honda 50 on my bike. The RS35 after 13 years and 5000 hours of use doesn't appear it's going to wear out in my lifetime lol

 

[ImpulseRocket]

Continued...

Frame reliability is also a huge consideration. As Jerry pointed out, there are bikes that can and have gone faster than 60mph. They aren't $200 machines, nor do they have the added weight and vibration of an engine.

Wheel bearings were also a great point that was touched on. I wouldn't trust a cup and cone bearing beyond 25 to 30mph. They aren't meant for that kind of loading, so you would want a wheel with roller bearings, at a minimum. I would also want thicker axles.

Some of this stuff.does exist, like Gemini wheels solving the last 2 points, but you are again talking about 400 bucks for wheels. Well worth it, to be sure, but not cheap.

A couple thousand dollars later you have a fast bicycle that may be reliable. But will still likely need a lot of maintenance to keep it going, and always a potential safety risk when pushing it to 60mph.

I would just buy a motorcycle at that point. That's literally what I did too. I bought my Hawk 250 in 2017 to replace my former MB because I wanted something that could safely, and reliably, do 60mph. I still have it, and I've been tinkering with it so much that basically every part of the bike has been upgraded or modified, and it now does 75mph, and accelerates way faster than it did stock with a much taller geared sprocket setup.

 

[ImpulseRocket]

I've got a Honda GXH 50 engine that's been on the shelf for 10 years now. I said I was going to put it on my Staton Inc gearbox when the Robin Subaru 35 wore out.

I've decided next year I'm going to put the Honda 50 on my bike. The RS35 after 13 years and 5000 hours of use doesn't appear it's going to wear out in my lifetime lol

That doesn't surprise me. 4 stroke with force air should last a very long time with basic upkeep.