The Shimano EP8 has motor over-run?

When interviewing Nick Murdick, a Shimano MTB product manager. We briefly talked about motor over-run, or carry-over. He told us the EP8 does in fact have over-run and it's only available in Boost mode. So, we tried to find it, and we compared the EP8 to the Bosch Performance CX. This video illustrates how the carry-over works and how to access it.


Doing drops​

If you’d rather just read, here’s the short version. We tried coasting, then hitting the pedals and doing less than a rotation, to have the motor lift the front wheel and keep it up as we went over a ledge. That was quite easy with the Bosch, and we got a bit of push out of the Shimano-motor too.

Going over obstacles​

We found what was supposed to be a short uphill climb with an obstacle at the top. We pedaled and paused over the rooty obstacle. The Bosch pushed us over, and so did the Shimano. We got the impression the duration of the push was shorter on the EP8.

A Merida with the Shimano EP8
We compared the EP8 to the Bosch Performance CX on this Orbea Wild.

A bit more difficult to access​

Using the over-run can be a bit difficult on the Shimano. It helps knowing how it’s supposed to work. Backpedaling will cancel the extra push. There is no play between the chainring and cranks on the EP8. So, it’s very easy canceling the carry-over when we stop pedaling and we don't succeed every time. To me it feels so natural just pushing the pedals slightly backwards when I stop pedaling. We tried to find the over-run in Trail mode too, but we don’t think we succeeded. Occasionally, we wondered if there was something. But we couldn’t say for sure, and in most situations, we didn’t feel anything.

Work in progress​

When talking to Nick more than a year ago, he said their Racing team was experimenting with motor over-run. I assume eventually there will be changes to how this works on the Shimano EP8 in software updates.
About author
knut7
Started mountainbiking in the 90s. Moved to emtbs in 2014 and have been reviewing them since 2016. Contact me here https://emtb.no/contact/

Comments

I would like to have an app option to toggle over-run off or on. Personally I'd like it off (Bosch). I don't like "relying" on it (or getting used to it) as it isn't something my non ebike has. It's not a big deal but would prefer the option to toggle it.
 
Hate over run. I want the motor to mirror my pressure on pedals perfectly - for me that's whole point of emtb. Otherwise just put in throttle. I don't care about beating a strava time if the feel of assist is not natural
 
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