[AndyIT]

Hi I have had a full knee replacment roughly one year ago and slowly getting back into cycling. I can put very little power or high cadence (as yet) though the leg that’s been ‘replaced’ and want a bike that I wil be able to use now and in the future that could take me up any reasonable hill. I will ride on my own and plan to have occassional group rides in slower speed groups. 

I don’t believe the 250w/300w motors e.g Fauza/Mahul hub motor bikes will provide me with sufficent power to get up steep hills. I am thefore looking at the Giant e+ pro bikes as they have a strong 500w motor but at the expensive of a circa 18-19kg bike weight. However I have read a review that stated the Gaint E+ pro provides a harsh ride at the front due to stiff forks.

I would be interested in the experience of anyone who has been in a similar postion or can talk about their experiences of the Giant electric e+ pro road bikes. 

Many thanks – Andy

 

 

 

 

 

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[AndyIT]

Hi many thanks for the

Hi many thanks for the feedback; that’s very useful. I am still working on getting the required flexion back (ligaments) as well as incresaing muscle strength. Hopefully over time it will come and so my longer term need might well be for lower assistance. In the short term I want the reassurance of having the power even if I don’t need all of it it. Maybe I just need to avoid hub motors as they won’t provide sufficient torque. I am partly drawn to the Giant as I have seen one at a good price significantly less than the Fazua systems (though being able to remove the system altogether is a nice feature of the Fazua systems). I have never reallly gauged my FTP but somewhere around 120-130w before my knee op at a guess though now it will be really very low maybe 50w.  

+Does a Fazua sstem stil provide good assistance if you are cyling slowly?  or does one need to hit a certain cadence for it to provide the full assistance? I have read that some systems ramp up the assitance (even on high power modes) only when the rider is putting out higher cadences?

[Cugel]

You’d be buying under a

You’d be buying under a misaprehension if you think that a mid-bike motor like the Fazua or similar is lacking in power to get you up hills. The Fazua Evation, for example, puts out 55-57Nm of torque and (assuming you yourself are not very heavy indeed) this will pull you up any British hill with relative ease, other than the very few monsters such as Wrynose or Hardknott.

We (me and the ladywife) have three Fazua-equiped bikes in our household, of the lighter e-bike variety (13.5kg, 14.5kg and 16.5 kg, one racey and the others more Audax style). We live and cycle in West Wales, which consists of nothing but hills, many of which are both long and steep.

Like many e-motors, the Fazua can be set to have various assistance levels and profiles. Currenty we tend to have a +80 watts, a +140 watts and a + 200 watts assistance setting, coming in gradually at 90 watts output from we riders and gradually increasing to those maximums as we riders increase our output to 120/180 watts (our respective FTPs) ourselves. We don’t use the potential 201 – 250 watts level of motor assistance, ever.

I weight 82 kilos and the ladywife weighs 56 kilos. My true FTP (what I can actually output for one hour or more, continously) is probably about 180 watts whilst the ladywife has an FTP (I’d guess) of around 120 watts.

Unless your knee is extremely delicate and/or you are very heavy, such a motor and the above-mentioned settings would easily allow you to tackle most British road-hills. Use the 250 watts max continuous output as well and you’ll probably beat either of us up any of those hills.  🙂

***********

Being 74, I have many friends and acquaintances who have new knee joints; and many also with artificial hip joints. Many cycle, run (even fell run) without issue, some at a high level despite their old age and joint replacements. Those artificial body bits are tough stuff! You can probably work up to a surprising fitness if you trust the surgeon who put yours in.

[Rendel Harris]

AndyIT wrote:

Ideally I would try out bikes but that’s very very hard to do (can’t find them locally and doubt they would allow a reasonsable test drive) so might just need to just take an educated guess.  

Not suggesting you would necessarily buy from them but if you want to try out an electric bike for a good period Halfords allow you to take a six hour test ride for £101 returnable deposit, see this page.

[Sriracha]

The limit being “250W
The limit being “250W continuous rated power” seems to be highly open to interpretation. It is in the nature of ebikes that the motor power output is intermittent – you’re often coasting or just ticking along, the duty cycle is well below 100%. So whilst the continuous rated limit might be 250W, it seems there is no limit to peak power over a limited, but nevertheless useful, period.

[mark1a]

Tom_77 wrote:

In the UK 250w is the maximum power for an eBike, anything more than that would be classed as a motorcycle or moped. You might have got mixed up between motor power (W) and battery capacity (Wh)?

If you’ve never ridden an eBike your best bet would be to go to a shop and try a few different ones.

I don’t think that’s quite true, my MTB has a peak power of 565W and torque of 90Nm and is completely legal, the 250W limit is continuous or nominal rated power, that is average over a period of time. Many e-bikes have a peak greater than that. 

Other than that, I agree, go to a shop and try them out. The place where I bought my MTB from had an open day in the Purbecks, and sent people out on a 20 min loop in the dunes in exchange for photo ID. 

[AndyIT]

Tom_77 wrote:

In the UK 250w is the maximum power for an eBike, anything more than that would be classed as a motorcycle or moped. You might have got mixed up between motor power (W) and battery capacity (Wh)?

If you’ve never ridden an eBike your best bet would be to go to a shop and try a few different ones.

Thanks Tom; yes the Giant has a 500w battery not motor. However I don’t think the actual output is actually properly checked but Giant use the bosch motor which has much greater torque than the other motors. 

Ideally I would try out bikes but that’s very very hard to do (can’t find them locally and doubt they would allow a reasonsable test drive) so might just need to just take an educated guess.  

[Tom_77]

In the UK 250w is the maximum

In the UK 250w is the maximum power for an eBike, anything more than that would be classed as a motorcycle or moped. You might have got mixed up between motor power (W) and battery capacity (Wh)?

If you’ve never ridden an eBike your best bet would be to go to a shop and try a few different ones.

 

[Author]

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