Giant bikes. Opinions on these two?

[soundwave]

Motor Diameter: 10.5 Inches
Motor Case Length: 11.25 Inches
Motor Shaft Length End to End: 12.25 Inches
Motor Type: Brushless Permanent Magnet
Brushes: No
Weight: 150 lbs.
Max Voltage Input: 360 Volts
Integrated Sensors: Encoder, temperature
Rated Torque: 280 Lb Ft Peak (w/150kW controller)
Rated Power: 210 HP Peak (w/150kW controller)
Max RPM: 10,000
Drive End Shaft: 32 spline 35.5 mm
Thermal Cooling: Internal oil pump with water heat exchange
Warranty Period:1 Year

 

[Woosh]

Which 250W Bafang them, the mislabled BBS02?

It's up to the manufacturer to label their motors.
you may call it mislabelled because I labelled my BBS02 as 500W, but the importer who got them may have asked Bafang for that '250W' label or they have decided to label the motors themselves as 250W.
Both approaches are legal.

There is no standardised method how to label the motors.

 

[anotherkiwi]

The Yamaha (SyncDrive) Giant with a double chainring will climb anything no matter how many stones you chuck at it. Tyres, brakes and suspension would be my concerns before worrying about the power of the motor.

I haven't fully tested the GSM at lowest gear (32:40) because I haven't found one steep enough that I'd feel safe riding back down on 15% I am in assistance level 4 and second (32:34) or assistance level 5 and third (32:28). Seated and twiddling the pedals.

 

[Blackbird]

Like i said, torque as just a number is very hard to compare.
I work in chemical industry, we have a system with a tiny motor that spins at an idiotic rpm 10 or a 100k or something like that. It is subsequently geared down to an absolute crawl and that drives a big chain conveyor to feed a dryer. Needs a lot of torque but very low rpms.
So the torque number at the drive end is very high with a low rpm. The torque number at the input end is very low with a high rpm.
So thats why it is very hard to compare a torque number without any data about rpm or rpm range.

 

[Woosh]

So thats why it is very hard to compare a torque number without any data about rpm or rpm range.

You get sometimes the power output charts for comparison.
Without the charts, I usually use the controller rating for comparison.
Most 36V performance motors run at around 20A.
Peak output at around 90 RPM.

Take this chart with a pinch of salt, but to illustrate, this chart shows the CX trounces the competition.

https://electricbikereview.com/forum/threads/ebike-motor-power-curve-comparison-chart-bosch-yamaha-shimano-brose.14085/

for comparison, the Bafang BBS02 uses 36V 25A controller, the BBSHD 48V 25A.

 

[Jamie82]

I definitely didn't get that feeling when i tried them though. I don't know what I'm talking about but think the cadence on the new yamaha is up from 90 to 110 so it shouldn't drop off quite so sharply as that illustrates

 

[Woosh]

I definitely didn't get that feeling when i tried them though. I don't know what I'm talking about but think the cadence on the new yamaha is up from 90 to 110 so it shouldn't drop off quite so sharply as that illustrates

that review was posted a year ago.
A year is a long lime in e-bike technology.
Also, I said take it with a pinch of salt.
You should follow the link and read the discussion for a balanced representation.

One poster said about the Yam:

The Yamaha has the correct curve generally speaking, although it doesn't drop off nearly that quickly. The peak is around 85 RPMs and it starts fading at about 95 RPMs. However you can still get good power out of it over 100 RPMs even in ECO mode. In fact it's a great way to save battery life. I often ride at 105RPMs on flatter sections, and it's clear to me that the chart is way off the mark above 100RPMs. I'm a really lazy person and I think I'd notice it if the drive provided close to 0 Watts assistance at that cadence...

another one about the Bosch:
Nice theory, but people who rode and compared different ebikes swears by the the positive characteristics and good qualities of the bosch design.

Another defends His Brose motor:

 

[Blackbird]

That is exactly what i mean, charts like those, if they use the correct numbers ofcourse, are the way you are able to compare different outputs. Maybe we will get independant scientific tests in the future.

 

[Trevormonty]

Forget charts its how motor feels to you that matters. More importantly how frame feels.

I definitely didn't get that feeling when i tried them though. I don't know what I'm talking about but think the cadence on the new yamaha is up from 90 to 110 so it shouldn't drop off quite so sharply as that illustrates

 

[Jamie82]

Having tried both I thought the Yamaha edged it.

Forget charts its how motor feels to you that matters. More importantly how frame feels.

To be honest I've been on three bikes and liked all of them. The giant was only in a medium frame in their showroom so a bit small. Gonna try and test ride a large today hopefully.

 

[RobbieBear]

Think I read in another thread somewhere that you bought the Giant Dirt E+ 2 Pro?
If so, how are you finding it? I am a similar weight.
Specifically:

• Performance on hills given only one front ring
• Comfort of frame for a) Relaxed longer riding on smooth surfaces b) Ability to soak up rougher, bumpy terrain with tree roots etc.
• The ease of fitting mudguards and lights (using bike battery)

I looked at the Oxygen MTB but after reading comments on this forum, I am a bit too heavy for that bike (20st but aiming to lose weight now).
Also, one of the big pulls of the Oxygen seems to be the ability to de-restrict it. Since I am not looking to do that, I decided to look elsewhere.

Others please chime in if you think I am on the right lines.

Budget is around £2500. At a pinch, I could stretch to the E+1 Pro (£2700) but there doesn't seem to be a lot of difference to my untrained eyes.

 

[Trevormonty]

Double chainrings are only need if want fit dongle to commute at 25mph+ while still have low climbing gear for very steep hills.
Otherwise 1x11spd is more than enough for most riders, plus lot easier than front derailluers to clean.

 

[soundwave]

Double chainrings are only need if want fit dongle to commute at 25mph+ while still have low climbing gear for very steep hills.
Otherwise 1x11spd is more than enough for most riders, plus lot easier than front derailluers to clean.

i got 12spd and two at the front

 

[RobbieBear]

Thanks for swift reply. That is good news!
I asked because I switched from a triple on a previous bike to a compact double on my current Merida CX4 bike and, these days, I miss the triple when going up hills due to lack of fitness. Electric makes all the difference I suppose.
I think the Dirt E+1 Pro has the 11 spd cassette. Would that be worth the extra few hundred over the +2 Pro. They both have air forks.

https://www.rutlandcycling.com/bikes/electric-bikes/giant-dirt-e-plus-1-pro-2018-electric-mountain-bike-orange_382063?origin=pla_with_promotion&kwd=&currency=GBP&gclid=EAIaIQobChMI-cGR5MyG3QIViPdRCh2EVQVHEAYYASABEgLrefD_BwE

and the cheaper bike

https://www.50cycles.com/giant-dirt-e-2-pro?gclid=EAIaIQobChMI_LGBlM2G3QIV7xXTCh0fZwWiEAMYASAAEgJNdPD_BwE

 

[RobbieBear]

i got 12spd and two at the front

Yeah, but you like to go really fast!

 

[soundwave]

you get a better group set and rock shox forks with the more expensive bike.

tho you could get the cheaper one and add better parts later but decent forks aint cheap.

so id pay the extra as i doubt you could get them forks and that group set under 400 quid.

 

[RobbieBear]

Thanks SW

 

[Jowwy]

The guy is 21st........I'm 18st 7lbs and fly up the hills on my cube acid one with Bosch active plus motor. He will have no problems with either of those giant bikes