Beware the "Gentle Assist" bike

TomWilcox

Member
By chance I met up with a group of fairly advanced riders today and made an unexpected observation.

My bike is a first generation electric bike - a big, fat, portly 37 lb Trek Domane+. I love it.

Understandably, when this bike came out a few years ago, serious riders scoffed at a bike weighing TWICE the weight of a decent 17 lb road bike and sales were flat.

Bike companies responded with a second generation of electric bikes with half the power, half the range, a smaller engine, and smaller batteries that brought down the weight of the bike to about 28 lbs. On paper it sounds like the perfect compromise for the serious rider that only needs a “gentle assist”, now and again. These bikes seem to be selling well. And there were a few of these gentle assist bikes with Fazua and e-motion motors amongst the more traditional bikes in the group I met up with. From the current advertising, I would have assumed that these bikes would have had a significant advantage over both the traditional bikes in the group, as well as myself on my heavy electric bike. I was wrong.

The group was strong and were drafting tightly enough for me to know that they were pretty serious. I joined them and clicked into sport mode. I had no problem keeping with the group even though I am fat and old.

Every once in a while the young guys at the front would get out of the saddle and sprint ahead for a bit in their super light bikes with the racing geometry. E-bikes have relaxed geometry and are heavy, so those of us with the electric bikes couldn’t compete in those reindeer games. Strangely, I noticed that the e-bikes were at the back of the pack. Our average speed was about 23-27 miles an hour which is a pretty brisk clip for me. The gentle assist bikes are Class I bikes which cut out at 20 mph. These bikes are about 10 lbs heavier than the regular bikes and the riders were riding without any assist because we were going too fast. What’s worse, many of the gentle assist bikes have a 46 tooth front chain ring in case they run out of power and have to peddle their heavy bikes home un-assisted. They couldn’t keep up with the regular bikes with a 50 or 52 tooth chain rings.

I had no such problems since I have a 50 tooth front chain ring and 400 watts of power assist to 28 mph. In fact, some of the fit young guys who were a bit jealous that a fat old guy was keeping up with the group nudged me to the front of the pack when there was a strong head wind, and since I was only a visitor to the group I was happy to pay my dues. I switched into turbo mode and pulled everyone along for a mile or two. One guy came up to me later and said, “ I have to take back all the bad things I said bout electric bikes.”

So if you’re thinking about spending about $6000-8000 for a beautiful Pinarello Nitro, Cannondale synapse Neo, Bianchi Aria E Road, Scott addict e-ride or Carbon Orbea Gain, realize that these bikes are class I “gentle assist” road bikes. Be aware that they are designed to be recreational bikes or fast touring bikes. These are terrific bikes to be sure, and their advantage for hill climbing cannot be understated. However, I was surprised that they can’t keep up with the the pros:

1) The relaxed geometry means you can’t sprint very well,
2) If your’e averaging more than 20 mph you get no assist, but you have to carry the extra weight of the motor and battery which will put you behind the regular bikes on the flats,
3) if you only have a 46 tooth front chain ring you can’t keep up with the pack who are riding a 50 or 52 tooth chain ring.

I’m a casual rider, and I’m happy to let the younger crowd race by, sweating and huffing. But if you NEED to keep up with the big boys, either stick with a light traditional bike, or make sure you get a class 3 bike that can assist you up to 28 mph.

(My sincere apologies to those who live in countries where class 3 are restricted.)
 

Stefan Mikes

Well-Known Member
Region
Europe
City
Brwinów (PL)
Have you considered Specialized Creo SL, a super-lightweight mid-motor Class 3 road e-bike with "Gentle Assist"? Just saying.
If I need to add anything to the above, I successfully competed with traditional roadies on mountain rides, riding my 28 mph (45 km/h) Specialized Turbo Vado (the full power, heavy e-bike). Where were the roadies better than I? Downhill. I am too cowardly to break my neck :)
 

Asher

Well-Known Member
Agree with all you said, and especially the ebike 20 mph limit.

Besides touring like you mentioned, it could be good for a novice or elderly roadie/group where the cruising speed is 20 mph or less, but that's fairly few roadies. Maybe it will create new roadies?

They make more sense for gravel, where the cruising speed is lower.

I think we'll see more entries like the Specialized Vado SL - fairly light and athletic, and only a drop bar away from being a road bike anyhow. A slow heavy electric road bike sort of suffers from the worst of both worlds. The bigger problem is the restrictive regulations limiting class 3 use in the big boy ebike market, the EU.
 

jabberwocky

Well-Known Member
It’s all about matching the bike to the use. A lot of the super upright class 1 bikes are oriented to commuting and general errand running, where outright speed is unimportant. Hence the upright position, wider heavier tires, etc.

If you want to keep pace with the hardcore roadie crowd you definitely want something that can be pedaled well into the 20s (either higher assist cutoff or light enough and low enough resistance that your fitness gets it there). A fit group of riders pacelining on road bikes can pretty easily sustain speeds in the 20s. It’s amazing how much a tight peloton makes a difference (a large group basically splits the air resistance among them, and air resistance is the dominant force acting against you once you’re above 14-15mph on your average road bike).
 

PDoz

Well-Known Member
Mixed rides say much about the group dynamics .

I'll wager those guys on the gentle assist bikes were transitioning from young and proud to being perfectly happy to be along for the ride? Quite happy to be working under their own steam mid pack, with the security of assist for the hills? Probably nothing to prove any longer , and most likely more " pro" than any of the young guns ?
 

TomWilcox

Member
There seems to be quite a lot of interest in "jail breaking" the lighter class 1 bikes to increase their assist to more than 20 mph. That suggests to me that there is a significant number of strong riders that want the lighter bikes, but want assist into the 20s. Maybe bike companies should take notice.

Although I'm happy with my 500 Wh battery, I seldom use more than half of the battery power on any single ride, so I'm essentially carrying around unusable weight. I have suggested to Trek that they offer an optional 250 Wh battery as a) an additional battery for really long rides, or 2) as a substitute when you want to do a shorter ride, less than 30 miles, and need to loose the extra weight when you're riding with the fast guys. I don't know if its electronically possible for a 250 Wh battery to supply the power needed for turbo mode at 65 Nm. Any engineers out there?
 

Dallant

Well-Known Member
There seems to be quite a lot of interest in "jail breaking" the lighter class 1 bikes to increase their assist to more than 20 mph. That suggests to me that there is a significant number of strong riders that want the lighter bikes, but want assist into the 20s. Maybe bike companies should take notice.

Although I'm happy with my 500 Wh battery, I seldom use more than half of the battery power on any single ride, so I'm essentially carrying around unusable weight. I have suggested to Trek that they offer an optional 250 Wh battery as a) an additional battery for really long rides, or 2) as a substitute when you want to do a shorter ride, less than 30 miles, and need to loose the extra weight when you're riding with the fast guys. I don't know if its electronically possible for a 250 Wh battery to supply the power needed for turbo mode at 65 Nm. Any engineers out there?
I suggest you ride longer so you’re making the “unusable” weight useable!😉
 

pmcdonald

Well-Known Member
It's been mentioned [citation needed] that a little while back Giant did some market research on customer battery use. Apparently most riders used far less than the capacity of their 400W and 500W packs at the time, so they brought out smaller 375W packs. Or it could just have been a cynical cost saving approach.

Either way, the experiment seems to have backfired a bit because the newer models return to 500W or even 625W batteries.

What we need and what we want can be two very different things.

When it's eventually time for a new bike I'd definitely have something with a 250W-375W battery, lighter assist and drop bars on the short list.
 
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Johnny

Well-Known Member
Yes 20mph limit somewhat defeats the purpose of a road ebike.

Although I'm happy with my 500 Wh battery, I seldom use more than half of the battery power on any single ride,

Can you share a ride(strava etc) that you spend %50 of the battery but average around 25mph? How many miles did you do? What was the elevation change.
 

Asher

Well-Known Member
It's been mentioned [citation needed] that a little while back Giant did some market research on customer battery use. Apparently most riders used far less than the capacity of their 400W and 500W packs at the time, so they brought out smaller 375W packs. Or it could just have been a cynical cost saving approach.

Either way, the experiment seems to have backfired a bit because the newer models return to 500W or even 625W batteries.

What we need and what we want can be two very different things.

When it's eventually time for a new bike I'd definitely have something with a 250W-375W battery, lighter assist and drop bars on the short list.

Bosch Powertube: going from 400 to 625 wh increases weight by 20%, 0.6 kg (3.5-2.9), but 56% in capacity.

A pound on a 35-60 lb ebike is not a big deal, especially when it means a whole lot less headache (not having to charge daily), and potentially longer battery lifespan (less deep discharging).

You may not need the bigger battery every day, but once a week or twice a month you might, and then what? All for a pound? Making small modular batteries would be a false economy by driving up the weight of housing per cell, and adding more housing cost.

Specialized took this tack, by using a 320 + 160 wh battery setup. It appealed to a lot of weight weenies, but ultimately as ebike awareness increases, I think this will be a niche play, akin to flat bar road bikes, because a low range ebike is just not very versatile. Esp since people increase their ebike range over time. It's a common refrain for people to wish they had gotten a bigger battery.
 

TomWilcox

Member
Yes 20mph limit somewhat defeats the purpose of a road ebike.



Can you share a ride(strava etc) that you spend %50 of the battery but average around 25mph? How many miles did you do? What was the elevation change.
On this particular day the group I was riding with were riding from the "M" casino in Henderson, Nevada which is on the outskirts of Las Vegas going South along Las Vegas Boulevard to the next small town, Jean, Nevada. It's about 20 miles each way. The roads are fairly straight and sparsely populated. After an initial moderate climb for the fist couple of miles, its a gentle down hill going South. It's a popular ride for groups of fast roadies. The disadvantage is that its open desert so its a) boring scenery, b) typically quite windy going one way or the other, so drafting is a must.
 

TomWilcox

Member
Bosch Powertube: going from 400 to 625 wh increases weight by 20%, 0.6 kg (3.5-2.9), but 56% in capacity.

A pound on a 35-60 lb ebike is not a big deal, especially when it means a whole lot less headache (not having to charge daily), and potentially longer battery lifespan (less deep discharging).

You may not need the bigger battery every day, but once a week or twice a month you might, and then what? All for a pound? Making small modular batteries would be a false economy by driving up the weight of housing per cell, and adding more housing cost.

Specialized took this tack, by using a 320 + 160 wh battery setup. It appealed to a lot of weight weenies, but ultimately as ebike awareness increases, I think this will be a niche play, akin to flat bar road bikes, because a low range ebike is just not very versatile. Esp since people increase their ebike range over time. It's a common refrain for people to wish they had gotten a bigger battery.
Agreed. I like my 500 Wh battery a lot. In a similar vein, years ago, I could get about 250 miles out of my old P85D Tesla. It was barely enough for long trips. From my experience, all those people currently buying Porsche Taycans for the speed, will soon realize that only getting 180 miles in a charge will be a huge headache.
 

FlatSix911

Well-Known Member
Region
USA
City
Silicon Valley
Agreed. I like my 500 Wh battery a lot. In a similar vein, years ago, I could get about 250 miles out of my old P85D Tesla.
It was barely enough for long trips. From my experience, all those people currently buying Porsche Taycans for the speed, will soon realize that only getting 180 miles in a charge will be a huge headache.
I agree and always recommend a larger battery for more range in EBikes and EVs... the new Tesla Model S 100D has over 400 miles of range. ;)
 

mogulskier

Active Member
2) If your’e averaging more than 20 mph you get no assist, but you have to carry the extra weight of the motor and battery which will put you behind the regular bikes on the flats,
3) if you only have a 46 tooth front chain ring you can’t keep up with the pack who are riding a 50 or 52 tooth chain ring.

Agree with both 2) and 3)

Swapping bikes with a specialized road bike, you can see why these guys can go so fast. I mean after riding a emtb that weighs in at 55 lbs and then riding a 30 lbs non-ebike is a huge difference.

After the guy gets his road bike back, he understands just how heavy these ebikes really are and those emtb tires are not helping at all.
 

Johnny

Well-Known Member
On this particular day the group I was riding with were riding from the "M" casino in Henderson, Nevada which is on the outskirts of Las Vegas going South along Las Vegas Boulevard to the next small town, Jean, Nevada. It's about 20 miles each way. The roads are fairly straight and sparsely populated. After an initial moderate climb for the fist couple of miles, its a gentle down hill going South. It's a popular ride for groups of fast roadies. The disadvantage is that its open desert so its a) boring scenery, b) typically quite windy going one way or the other, so drafting is a must.

On a flat circuit without many stops, if you are also using drops +averaging 150-200W yourself it is doable I guess. However that still translates into only 5wh/mile and to be honest that is quite unrealistic for averaging 25mph in most cases...
 
By chance I met up with a group of fairly advanced riders today and made an unexpected observation.

My bike is a first generation electric bike - a big, fat, portly 37 lb Trek Domane+. I love it.

Understandably, when this bike came out a few years ago, serious riders scoffed at a bike weighing TWICE the weight of a decent 17 lb road bike and sales were flat.

Bike companies responded with a second generation of electric bikes with half the power, half the range, a smaller engine, and smaller batteries that brought down the weight of the bike to about 28 lbs. On paper it sounds like the perfect compromise for the serious rider that only needs a “gentle assist”, now and again. These bikes seem to be selling well. And there were a few of these gentle assist bikes with Fazua and e-motion motors amongst the more traditional bikes in the group I met up with. From the current advertising, I would have assumed that these bikes would have had a significant advantage over both the traditional bikes in the group, as well as myself on my heavy electric bike. I was wrong.

The group was strong and were drafting tightly enough for me to know that they were pretty serious. I joined them and clicked into sport mode. I had no problem keeping with the group even though I am fat and old.

Every once in a while the young guys at the front would get out of the saddle and sprint ahead for a bit in their super light bikes with the racing geometry. E-bikes have relaxed geometry and are heavy, so those of us with the electric bikes couldn’t compete in those reindeer games. Strangely, I noticed that the e-bikes were at the back of the pack. Our average speed was about 23-27 miles an hour which is a pretty brisk clip for me. The gentle assist bikes are Class I bikes which cut out at 20 mph. These bikes are about 10 lbs heavier than the regular bikes and the riders were riding without any assist because we were going too fast. What’s worse, many of the gentle assist bikes have a 46 tooth front chain ring in case they run out of power and have to peddle their heavy bikes home un-assisted. They couldn’t keep up with the regular bikes with a 50 or 52 tooth chain rings.

I had no such problems since I have a 50 tooth front chain ring and 400 watts of power assist to 28 mph. In fact, some of the fit young guys who were a bit jealous that a fat old guy was keeping up with the group nudged me to the front of the pack when there was a strong head wind, and since I was only a visitor to the group I was happy to pay my dues. I switched into turbo mode and pulled everyone along for a mile or two. One guy came up to me later and said, “ I have to take back all the bad things I said bout electric bikes.”

So if you’re thinking about spending about $6000-8000 for a beautiful Pinarello Nitro, Cannondale synapse Neo, Bianchi Aria E Road, Scott addict e-ride or Carbon Orbea Gain, realize that these bikes are class I “gentle assist” road bikes. Be aware that they are designed to be recreational bikes or fast touring bikes. These are terrific bikes to be sure, and their advantage for hill climbing cannot be understated. However, I was surprised that they can’t keep up with the the pros:

1) The relaxed geometry means you can’t sprint very well,
2) If your’e averaging more than 20 mph you get no assist, but you have to carry the extra weight of the motor and battery which will put you behind the regular bikes on the flats,
3) if you only have a 46 tooth front chain ring you can’t keep up with the pack who are riding a 50 or 52 tooth chain ring.

I’m a casual rider, and I’m happy to let the younger crowd race by, sweating and huffing. But if you NEED to keep up with the big boys, either stick with a light traditional bike, or make sure you get a class 3 bike that can assist you up to 28 mph.

(My sincere apologies to those who live in countries where class 3 are restricted.)
I am so glad to see your post! I had always thought the same thing! Why spend all that money on something that doesn't go fast! I mean at least they go faster then those that stop at 15.5 miles per hour but again what is the point? I guess people buy them to hide they are a ebike but yet they are!