Shimano motor consistently cuts out early

RickBullotta

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Jun 5, 2019
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Hi, all. I've noticed that the E8000 on my Pivot Shuttle consistently cuts out around 18 MPH rather than the rated 20 MPH. It's not a big issue for everyday riding, but I just did my first eMTB race, and in the open stuff when hammering hard on the pedals, it was a HUGE disadvantage versus the Specialized Levo's I was racing against. Anyone else notice this? I had a shop take a look and they recalibrated wheel size and then spoke with Shimano who said that they start tapering off boost at 18 - I find it to more or less just turn off. On the plus side, the Shuttle kicked ass in the slower technical stuff, but I'd sure like to have it calibrated and set up so I get boost all the way to 20 MPH. Any input welcomed.
 

Gary

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have you updated the firmware.
18months ago my first E8000 when new used to cut assistance at around 14mph instead of the 15.5mph limit (UK). subsequent firmware updates improved this greatly.

I believe you can alter more settings with the shimano steps software using a PC but this requires a hardware interface (PC-E1)
 

RickBullotta

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Jun 5, 2019
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have you updated the firmware.
18months ago my first E8000 when new used to cut assistance at around 14mph instead of the 15.5mph limit (UK). subsequent firmware updates improved this greatly.

I believe you can alter more settings with the shimano steps software using a PC but this requires a hardware interface (PC-E1)

Yes, latest firmware. It's a design flaw and one that Shimano seems to refuse to acknowledge. Confirmed with other riders of US-spec Shimano E8000's. Tunability is far inferior to the Brose-based Specialized system (and the 2.1 motor is ridiculously good). The capability is probably all there, but the software doesn't allow the flexibility needed to dial your bike in for the way you want to ride.
 

raine

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May 9, 2019
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Not discounting your issue here, but I'm just gonna throw this in: I'm on firmware 4.6.1, I'm in the U.S., my E8000 is U.S.-spec, and the power does start to taper off at around 18-20mph. It doesn't feel like it's immediately switching from on to off (I think that's how you are describing it)... so not sure what's up with your bike. But if it was a "design flaw" then it would be the same with everyone on E8000.
 

RickBullotta

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Jun 5, 2019
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Not discounting your issue here, but I'm just gonna throw this in: I'm on firmware 4.6.1, I'm in the U.S., my E8000 is U.S.-spec, and the power does start to taper off at around 18-20mph. It doesn't feel like it's immediately switching from on to off (I think that's how you are describing it)... so not sure what's up with your bike. But if it was a "design flaw" then it would be the same with everyone on E8000.

The big issue is "18-20". It's either 18, or it's 20. In my case and a couple people I know's case, it's 18. Gimme 20 and I'm happy, steep dropoff or not. ;-)
 

raine

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The big issue is "18-20". It's either 18, or it's 20. In my case and a couple people I know's case, it's 18. Gimme 20 and I'm happy, steep dropoff or not. ;-)

I said "18-20" because it's somewhere in there... I don't stare at my display to get the EXACT number when the power starts to feel like it's tapering off, I focus on riding =)
 

RickBullotta

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I said "18-20" because it's somewhere in there... I don't stare at my display to get the EXACT number when the power starts to feel like it's tapering off, I focus on riding =)

Ha. Truth. I really don't care at all for every day riding - I love the way it rides. It's just for racing that those 2 MPH actually made a difference. I was hammering at 100% the whole time, but the guys on the newer Specialized Levo's were pulling away on the open stuff because of it.
 

raine

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Ha. Truth. I really don't care at all for every day riding - I love the way it rides. It's just for racing that those 2 MPH actually made a difference. I was hammering at 100% the whole time, but the guys on the newer Specialized Levo's were pulling away on the open stuff because of it.

Yeah, I can see how in a competition environment that can be an issue... if it's that big of a deal when racing, then maybe you should be on a Levo as well. Hahah
 

Brianjonesphoto

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You are racing an ebike. :unsure: You get what you get. If you want to go faster pedal harder like you would on a regular bike. Mountain out of a mole hill. All speedometers that are not gps based generally read 8–10% slow to keep the manufacturer on the radar side of a lawsuit.

As will all motorsports the answer is how fast you want to spend.
 

Gary

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Ha. Truth. I really don't care at all for every day riding - I love the way it rides. It's just for racing that those 2 MPH actually made a difference. I was hammering at 100% the whole time, but the guys on the newer Specialized Levo's were pulling away on the open stuff because of it.

You want "truth" ?
Racing Ebikes "seriously" is pretty stupid

it's an arms race so you might as well just de-restrict it. That way assistance tapers off more naturally at a far higher speed
 

papab

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Jun 10, 2018
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I think mine starts to taper at 18 mph and is done at 20. I think that's a good way to do it, I'd rather not have a sharp cutoff. Commencal with Shimano.
 

RickBullotta

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Yeah, I can see how in a competition environment that can be an issue... if it's that big of a deal when racing, then maybe you should be on a Levo as well. Hahah

...except that I like to go downhill fast too. ;-) The Shuttle is an absolute beast on the descents and in technical terrain. I have a few DH PR's on the Shuttle - which is surprising since my "everyday" bike is a Santa Cruz Hightower setup with an enduro tuned suspension. Speaks volumes to the suspension design on the Pivot and the benefits of the low center of gravity.
 

RickBullotta

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Jun 5, 2019
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You want "truth" ?
Racing Ebikes "seriously" is pretty stupid

it's an arms race so you might as well just de-restrict it. That way assistance tapers off more naturally at a far higher speed

Um, have you tried it? It's f*cking awesome. You're pushing as hard as you would in a regular XC race or a cyclocross race, just going faster - which demands better bike handling skills. Race lengths are a bit longer than a cross race, like a short XC race. Last one we did 16.5 miles (including some gnar in the woods) in 1:02. That's hauling ass. My HR *averaged* above 150 - same range as an XC race or cross race (or enduro).

De-restricting is cheating - there's a tech inspection before each race.
 

RickBullotta

E*POWAH Elite World Champion
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You are racing an ebike. :unsure: You get what you get. If you want to go faster pedal harder like you would on a regular bike. Mountain out of a mole hill. All speedometers that are not gps based generally read 8–10% slow to keep the manufacturer on the radar side of a lawsuit.

As will all motorsports the answer is how fast you want to spend.


"Pedal harder" - ha. I wish. My HR was pegged (average was 153) and I was COOKED afterwards. That was a full 100% effort. Nothing more to give.

I do agree with you though that since "machine" makes a bit more difference in this form of racing, that people will buy their way onto the podium. Oh well, it was still fun as hell.

Gotta go ride now.
 

Gary

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It's f*cking awesome. Blah blah...

Yeah. I'm not disputing it being awesome fun.
I'm disputing it being anywhere close to a level playing field because of the huge differences in motors, torque and control available from all the different manufacturers motors. As pointed out by your good self assist cut out speed isn't even the same between them.

Unless this is somehow addressed I just can't see how anyone could genuinely take it seriously.
 
Last edited:

HORSPWR

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May 23, 2019
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Um, have you tried it? It's f*cking awesome. You're pushing as hard as you would in a regular XC race or a cyclocross race, just going faster - which demands better bike handling skills. Race lengths are a bit longer than a cross race, like a short XC race. Last one we did 16.5 miles (including some gnar in the woods) in 1:02. That's hauling ass. My HR *averaged* above 150 - same range as an XC race or cross race (or enduro).

De-restricting is cheating - there's a tech inspection before each race.

How do they check that you haven't set your rear wheel circumference smaller there by tricking your computer into thinking your going slower than you really are and then your speed limit cutoff is raised?
 

RickBullotta

E*POWAH Elite World Champion
Jun 5, 2019
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Yeah. I'm not disputing it being awesome fun.
I'm disputing it being anywhere close to a level playing field because of the huge differences in motors, torque and control available from all the different manufacturers motors. As pointed out by your good self assist cut out speed isn't even the same between them.

Unless this is somehow addressed I just can't see how anyone could genuinely take it seriously.

True that. I agree.
 

RickBullotta

E*POWAH Elite World Champion
Jun 5, 2019
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Could it not be tyre size that gives the speed discrepancy? Maybe you could use the Steps Unlocker to set the correct tyre size. I don't think that would be cheating.

Gordon

I had a local shop on the phone with Shimano and they set everything to spec. I've tracked it with an accurate GPS on a straight path and the speed indication is correct. The issue is that the boost is cutting out between 18.3 and 18.5 MPH instead of 20 MPH. So be it. I'll just enjoy it as is and skip eMTB racing, or better yet, do some enduros on it!
 

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