tim.hillsamer


tim.hillsamerGranny Gear

3 points (view top contributors)
Canterbury // NEW ZEALAND
tim.hillsamer > Forum Activity
 

Forum Replies Created

Viewing 4 posts - 1 through 4 (of 4 total)
  • Author
    Posts
  • Ascending and spinning is where trails get truly dug up.   On a bicycle, with no motor, you just end up walking/pushing.  With even a little bit of additional power, everything changes and the trails change quickly with it.  Not to mention that the addition of power to riding opens up a greater population of people who want to use the same trails, and more often.

    And power-assist summed with lack of riding skill is very different than skill added to gravity.  Anyone who can descend, and move dirt doing it, will quickly find themselves moving dirt everywhere else when they have even a little bit of power asist at their disposal.

    I think the responses here speak to prove my point:  very few of us see what’s most likely  coming as e-bikes evolve and gain strength in numbers and enthusiasts, and in reliability and power and range and utility.

  • You can clearly see positive wheelspin and moving dirt int his video, FROM BOSCH:

  • I have seen this happen in many many motorcycle scenarios, from local areas that have signs that politely ask “Please do not ride when the trails are wet.” …to sections of a racecourse(through the pits, in transfers at enduros, part of a course that crosses private land) where speed and aggression are asked to be limited – it never works, there is always a contingent who disregards it, and then the rest is history.  Almost all current pedal-only-established MTB trails consititute places that need to be treated with stewardship – especially backcountry ones – and e-bikes will eventually turn them into very different trails even in their current state of “detune” and present natural limitations.

    All due respect, but you’re way off about the CR80 – even a dying one that needs rings has 18+hp on the pipe; a healthy on has 25+.  You are correct in that it’s the delivery(peaky torque curve) of the power(and torque) that promotes wheelspin, but it can be ridden pretty fast without wheelspin.  The “problem” is that it’s just too much fun to light the tire up and let ‘er rip.  Most riders would never have the throttle control to “tread lightly” as it’s easier just to deal with the wheelspin, trail damage be damned, than to try and control it.  And besides, it’s fun to just scream the thing and drift around on the rear wheel if you’ve got the skill.

    An XR80 has about 7-9hp(hence my comparison), equivalent torque and a much smoother delivery, but with some clutching and a lot of revs it can be made to do plenty of what would be considered “severe” trail damage in the eyes of the MTB world.

    Regardless, it is human nature to want “more,” and eventually that will creep in and be doing far more damage to trails than “enough” will.  Hence my reccomendation that some sort of traction control – implemented as standard across the industry, NOW, instead of later, would be a wise move for everyone invovled and in the end, will not have much effect ont he fun factor.

    IME, with a mid-drive e-bike and 500 watts, properly shifted to keep the torque of the motor high, you can induce plenty of “fun” wheelspin where you could not have on a pedal-only bike.  Fun = trail “damage” IME.

  • There is no right or wrong here.   It’s only a discussion and all scenarios are possible.  And I respect your opinion, but you do lack understanding of what I’m suggesting.

    Nobody has self-restraint when they have unlimited power at their disposal.  Or at least, a rare few will, as has been proven by anythign else motorized when used recreationally.

    You’re only wrong with the reference to popping wheelies.  If you’re already riding along, and go to lift the front wheel with pedal torque + electric assist, it will do it.  It also would have no effect on doing it with pedal power alone.  This would be the case whether it was a power-wheelie, or a balance-wheelie(‘manual’) just the same.  That’s the idea behind the ~5% or whatever close margin.

    Said margin is also needed if you want to make tight turns with the e-assist, too

    It wouldn’t be the wheelie police at all, unless you and your e-motor can break the rear tire loose and exceed the front wheel speed when you lifted it by ~5% DURING the wheelie.  At which point you’re already at the balance point and pedaling or manualling anyway.

    For a short time on dirt or sand, most capable MTBers can make the rear wheel RPM exceed front RPM under pedal power alone by maybe 20% at the most.  And only a short time at that.

    “Roosting” a berm on an MTB is a far, far smaller cry from what you can do with even 10hp on an old XR80 under power.  And e-bikes at ~500+ watts of motor output have enough torque to probably match the XR80 up to say 25mph.

    Chances are if you’re doing a power wheelie long enough for the front wheel to slow down and remove assist(or simply under pedal power alone), you don’t need the e-assist at that point anyway.   By definition, if you are doing a manual, you aren’t pedaling anyway, so it wouldn’t matter or be noticed.  As soon as you set the front wheel down again, speed match, and you get your electric assist back as fast as you can start pedaling again.  The chances of the undriven front wheel slowing down to the threshhold of 5% slower RPM than the driven rear wheel during either type of wheelie are slim to none – unless your front brake is dragging even slightly or you’ve got really bad wheelbearings…which you would have noticed whether it was an e-bike or not.  Or, you use the front brake during the wheelie, which you’d learn not to do or didn’t need to be in the first place.

Viewing 4 posts - 1 through 4 (of 4 total)