Bosch 4th gen motor

[Buttonjaw]

Hi

My name is Scott and I live in Portland, OR.

So I’m currently debating between the Tern HSD P9 Performance and Tern HSD S11 but what I really want is 85nm of torque (which neither of these models provide). Perhaps I should wait for Tern to integrate the Bosch 4th gen motor into their next HSD model? Anyone have any thoughts of when that might be?

many thanks!

 

[rich c]

Curious why you are so specific on the need for 85nm of torque. Have you ridden Bosch powered eBikes and found them lacking? My 2016 Haibike Full Seven climbs single trails like a mountain goat. I find a lot of new riders do a little too much reading and not enough riding to make that kind of decision.

 

[Buttonjaw]

Hi Rich,

Thanks for chiming in.

Here’s some more background. I’ll be carrying myself (6’3” 200 lbs) on my daily work commute when COVID-19 restrictions are lifted (so maybe 4-6 months). My commute includes a 10% grade incline for over a mile and I’d like to ensure the motor can handle the job. I’m not sure about this but I imagine the jump from 65nm torque (Bosch Performance Line Gen 3) to 85nm torque (Gen 4 motor) will make the commute easier so I’m trying to avoid investing in 4-year-old motor technology when Tern could easily introduce an HSD S11+ in a few months which utilizes newer motor tech.

I’ve setup a test ride for this week to test both models and will report back my findings.

 

[fooferdoggie]

Hi Rich,

Thanks for chiming in.

Here’s some more background. I’ll be carrying myself (6’3” 200 lbs) on my daily work commute when COVID-19 restrictions are lifted (so maybe 4-6 months). My commute includes a 10% grade incline for over a mile and I’d like to ensure the motor can handle the job. I’m not sure about this but I imagine the jump from 65nm torque (Bosch Performance Line Gen 3) to 85nm torque (Gen 4 motor) will make the commute easier so I’m trying to avoid investing in 3-year-old motor technology when Tern could easily introduce an HSD S11+ in a few months which utilizes newer motor tech.

I’ve setup a test ride for this week to test both models and will report back my findings.

10% grade is not that much. I am not that healthy and I can do that well in tour on my performance speed and it only has 63

 

[Buttonjaw]

Great thanks for letting me know. I’m relieved to know that 65nm will be enough assist for me.

And let’s hope 2021 is a healthier year for you.

 

[Dallant]

Hi

My name is Scott and I live in Portland, OR.

So I’m currently debating between the Tern HSD S9 Performance and Tern HSD S11 but what I really want is 85nm of torque (which neither of these models provide). Perhaps I should wait for the Bosch 4th gen performance line to be introduced? Anyone have any thoughts of when that might be?

many thanks!

Apparently you’re waiting for the Tern version of the gen 4 PLCX. The 4th Gen Bosch Performance Line CX (on my Trek Allant+7) is out there and the dealer software update provides the 85Nm of torque. Great motor IMO!

 

[fooferdoggie]

Great thanks for letting me know. I’m relieved to know that 65nm will be enough assist for me.

And let’s hope 2021 is a healthier year for you.

best to test ride to make sure. but I have climbed 17 % grades with only al little difficulty and 20% grades with a lot of work. wife and i's tandem just has the performance motor and we can club 16% grades and a little steeper for a block or so. we have done light mountain biking with it. My heath will Neve be normal I don't think but biking as sure improved it a lot. if you want to work out on the bike then you don't need a huge amount of torque especially not on a bike that is not a speed bike.

 

[rich c]

I’m 68 and weigh 250 if that helps in understanding that you don’t have to have the extra 20Nm. I’ve ridden 12,500+ miles and haven’t had to push an eBike up a hill yet. Well I take that back. I fell on a tight switchback on some damp roots on a single trail. I was half way up a steep climb and no way I could balance and start up again. But just that once.

 

[Buttonjaw]

I test rode 5 eBikes and ended up pulling the trigger on Tern HSD S11. It was by far the best quality bike I rode. My top 6 reasons:

1) Class 3 Bosch performanceLine Sport motor (28mph)
2) Magura brake system (MT5 4-piston on front, MT4 2-piston on back)
3) Shimano® Deore XT shifter/derailleur
4) Intuvia display (ability to power usb devices a big plus)
5) cane creek suspension seat post
6) Suntour Mobie a32 suspension fork

So far I am thrilled with S11.

 

[TOOSLOW]

Tern is a good quality bike, the only cons I see are,
weight,
small range cassette,
needs to be de-restricted.
Overall though, a top notch unit.

 

[Dallant]

Tern is a good quality bike, the only cons I see are,
weight,
small range cassette,
needs to be de-restricted.
Overall though, a top notch unit.

YOU need it to be de-restricted. Some of us are just fine with 20 mph max.

 

[Alaskan]

YOU need it to be de-restricted. Some of us are just fine with 20 mph max.

The OP is young and using the bike to commute. Given that I would suggest he consider derestrict the CX motor AND put a wider range cassette on the bike if it will accommodate it. Adding three teeth will enhance the ability to use the dongle as it will extend the top gear ratio. Changing cassette to one with a larger low gear chain ring will recapture lost high climbing ability due to the larger chainring.

Adding a dongle like the Bikespeed RS from Germany takes a very good, strong, hill climbing motor and eliminates the 20 mph cut off. For a commuter being able to travel at 25mph is a real game changer for safety. It allows you to travel at the same speed as city traffic where you can "take the lane" and not have passing cars squeezing you too close to parked cars, risking opening car doors. That with good bright clothing and good lights would make him much safer.

The only issue with derestricting the motor (adding a speed dongle) is the potential loss of warranty. Fortunately he has the gen 2 motor which lacks the detection and disabling software of the gen 4. Many of us have thousand of miles on derestricted Bosch gen 2 CX motors.

Before making any changes I would strongly suggest the OP not do anything but ride and get to know his bike. It may be perfect for him just the way it is. After a month of daily riding, he will have a better idea as to what, if any, mods might make the bike suit him better.

 

[cj3209]

I test rode 5 eBikes and ended up pulling the trigger on Tern HSD S11. It was by far the best quality bike I rode. My top 6 reasons:

1) Class 3 Bosch performanceLine Sport motor (28mph)
2) Magura brake system (MT5 4-piston on front, MT4 2-piston on back)
3) Shimano® Deore XT shifter/derailleur
4) Intuvia display (ability to power usb devices a big plus)
5) cane creek suspension seat post
6) Suntour Mobie a32 suspension fork

So far I am thrilled with S11.

That is a lot of money for that bike ($4,500usd) and it weighs around 55lbs!

 

[Luto]

Also note a Bosch 3 will not have any replacement crank options since it uses the Mini ISSI spindle, Bosch Narrow interface (BNI). I think the Gen 4 goes back to the normal ISSI spindle, like the gen 2, for which there are many after market choices.

Also FWIW, I found the smaller wheels prone to slippage due to the torque, when I rode the Terns.

 

[Buttonjaw]

That is a lot of money for that bike ($4,500usd) and it weighs around 55lbs!

True. Although I actually paid $4199 (the original MSRP) before the price hike. I’m also optimistic the E-BIKE act will get passed this year:

(https://electricbikereview.com/foru...ike-act-federal-tax-credit.40754/#post-389474)

which will give a 30% refundable tax credit on E-bike purchases. Fingers crossed

 

[cj3209]

True. Although I actually paid $4199 (the original MSRP) before the price hike. I’m also optimistic the E-BIKE act will get passed this year:

(https://electricbikereview.com/foru...ike-act-federal-tax-credit.40754/#post-389474)

which will give a 30% refundable tax credit on E-bike purchases. Fingers crossed

Does that apply to retro purchases? LOL...

 

[Buttonjaw]

Apparently you’re waiting for the Tern version of the gen 4 PLCX. The 4th Gen Bosch Performance Line CX (on my Trek Allant+7) is out there and the dealer software update provides the 85Nm of torque. Great motor IMO!

Just checked out your bike. Wow! That is one impressive monster of an eBike. That's the motor that Tern uses in their GSD line of Cargo bikes. I'm sure Tern will incorporate those into the HSD at some point.

Did you get the 170mm crankset or 175mm? The one thing I'd change about the S11 is the size of the crankset. It comes with a 170mm but I've found that on declines that my RPMs are pretty high. It's not enough to change it out but something that's a little aggravating. Happy riding!

 

[FezUSA]

Does that apply to retro purchases? LOL...

Not the way it's currently proposed, it will only be for ebikes purchased AFTER the bill passes. But who knows what will be changed between proposal and passage?!!!

 

[cj3209]

Not the way it's currently proposed, it will only be for ebikes purchased AFTER the bill passes. But who knows what will be changed between proposal and passage?!!!

No worries.

I just don't want people with eBikes always wanting more speed (above 28mph) and getting non-ebikers all riled up because we're flying by them on the trails...

 

[Dallant]

No worries.

I just don't want people with eBikes always wanting more speed (above 28mph) and getting non-ebikers all riled up because we're flying by them on the trails...

It’s gonna happen. Just look at the idiots on this site constantly beating the higher speed drum. They should just buy e-motorcycles. They will run over some child or older woman and completely piss all the hikers, walkers, rangers, etc, etc. and then the limiting legislation will roll in.