Wisper 905se advice

Electrically assisted bikes, trikes, etc.
Spud60
Posts: 1
Joined: 3 May 2020, 5:11pm

Wisper 905se advice

Postby Spud60 » 3 May 2020, 5:25pm

I have got a Wisper 905se bike ( its quite old but like new )and I intend to ride my bike to get fit as I'm on the large size, the bike is great ride around but when I get near my house is up a very steep hill which I can't make at the moment and I end up stopping and walking up the hill which is a good mile up the hill, which could take a while as the bike is quite heavy , the bike has 7 gears which I use the largest one but its still no good.
Would it benefit me to change the rear gears for larger or front sprocket if possible, or even change the 250watt motor if possible.
Can you please advise the best solution.

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531colin
Posts: 12977
Joined: 4 Dec 2009, 6:56pm
Location: North Yorkshire

Re: Wisper 905se advise

Postby 531colin » 3 May 2020, 7:03pm

Have a read of this https://www.pedelecs.co.uk/forum/threads/getting-me-my-child-and-4-bottles-of-beer-up-a-mountain.36904/
I think your bike has a hub motor, so the motor doesn't drive through the gears.
250W is the legal maximum; the Pedelec forum guys seem to think you need a geared hub or better a mid motor which drives through the gears.

stodd
Posts: 282
Joined: 6 Jun 2018, 10:24am

Re: Wisper 905se advice

Postby stodd » 3 May 2020, 9:35pm

Not a long term solution, but it probably has a walk mode which would at least help you get it up the hill.

I don't know the details of it, but I'm almost certain the 905se has a geared hub motor. But as 531colin says, a mid motor which drives through the gears is best for very steep hills. With the geared hub drives their gearing is still fixed, so changing your gears will help with your effort, but not with the effort from the motor. They produce a bit more torque but less power as they go slower; they are quite inefficient by the time you are down to 6mph or so. One thing that can help is getting the motor on full power and max speed you can get to before you start on the hill; but that's not going to make any significant difference on a long hill like that.

Another possible problem is that the battery is past its best (especially at the end of a ride). It will still charge up to full voltage, but voltage will sag quickly as you try to get power from it. You'd probably see that from the display showing a battery drop as you apply more power. If it's more than 5 years old it's almost certainly worth replacing. Batteries can also suffer if they have extended periods without use for any reason. It will probably be a fairly expensive option (but nowhere near as expensive as it would be on a Bosch powered bike).

Ask at the pedalecs site colin mentions for more suggestions. https://www.pedelecs.co.uk/forum/forums ... cussion.2/

hemo
Posts: 775
Joined: 16 Nov 2017, 5:40pm
Location: West Sussex

Re: Wisper 905se advice

Postby hemo » 4 May 2020, 11:02pm

Wisper bikes usually use a high torque hub ( a geared hub) which means it will freewheel. the answer like any bike is to change the gearing but depends on the rear derailleur and the lowest gear it can take. They are over geared for steeper hills so gearing is the answer so probably a smaller toothed front ring.
https://www.pedelecs.co.uk/forum/thread ... iews.1894/
Pedelecs have a dedicated Wisper clinic on the forum.

artspeck
Posts: 2
Joined: 14 May 2020, 9:29pm

Re: Wisper 905se advice

Postby artspeck » 14 May 2020, 9:38pm

I understand the Pedelecs forum is owned by Wisper bikes, and I’m sure you will get all the help you need from David the owner, a lovely man.

stodd
Posts: 282
Joined: 6 Jun 2018, 10:24am

Re: Wisper 905se advice

Postby stodd » 15 May 2020, 9:28am

Is that the whole Pedalecs forum that is owned by Wisper, or just that Wisper moderate their thread?

Either way I think those of us that use the forum will agree that it doesn't show any undue Wisper bias; just a consistent view that Wisper (along with a few others such as Woosh and Juicy) are very good to deal with.

hemo
Posts: 775
Joined: 16 Nov 2017, 5:40pm
Location: West Sussex

Re: Wisper 905se advice

Postby hemo » 15 May 2020, 11:19am

Pedelecs forum isn't owned by Wisper bikes or David Miall , they/he is a trade member who pays a fee to advertise on the site.
All I know is the administrators of the forum go by the names of Russ & Helen who very seldom post on the forum, the only form of moderation is self moderation and on very rare occasions they will lock a thread if it gets out of hand.
Last edited by hemo on 15 May 2020, 7:38pm, edited 1 time in total.

stodd
Posts: 282
Joined: 6 Jun 2018, 10:24am

Re: Wisper 905se advice

Postby stodd » 15 May 2020, 2:36pm

@Hemo, thanks for the clarification.