I would say ride it with the power off , no drop off point and will drag from the outset,then go to Halfrauds, get a test ride on a new one, see it that is the same and take it from there for resolution, my A2B metro was impossible to ride with motor switched off, my MTB with crystalyte hub dragged once the battery switched out with LVC or highest speed setting attained. Then it's just Man V 20 kilo plus of behemoth bike....... Bike wins, leaving a sweaty rubber legged pedelecer on kerbside gasping for air and water.

Yes, but just to make it clear to those that don't know, both those bikes have non-freewheeling motors, so completely different to OP's.

I have experienced the same feeling of drag when using zero assist. Quite a resistance when peddaling.

I Turned the power off at the battery rode the bike and no resistance (drag) at all. Turn the power back on rode with assist then went to zero assist again and a definate drag.

Anyone one else have a big issue with serious drag back from the hub with this bike? If doing about 16.5 /17.8mph on the flat I get a real drag/hub brake engagement. The harder I pedal the worse it gets. If I can get past this speed downhill, its fine. On a flat I'm stuffed. Why would it have such drag at this speed? I know they are limited but would expect the electric to cut out but not put the hub/brake/drag on to the extent that it I have to stop peddling and than wait to drop under 15mph before starting peddling again. Really getting on my nerves!

 

I test rode this bike a week ago and that was my exact experience. I put it down tot the assistance cutting out. It was very off putting. I tend to agree with D8veh's explanation.

I too have a similar problem on my 2-week old crossfire E but there are differences.

On mine the drag happens about 12 mph on the flat or going downhill when no assistance is dialled in or required. And the harder I pedal the more the drag seems to increase. If I stop pedalling the bike freewheels OK.

It doesn't happen all the time - it seems to be about 30 minutes into a ride. And I can sometimes cure it by dialling in some assistance, accelerating up to 17 or 18mph then switching off and pedalling is Ok (well as good as can be expected from a 30kg bike (with my accessories).

I have read some of the possible explanations above, and would be grateful if those knowledgeable guys could tell me what to tell Halfords to check when it goes in for its first service.

(loving the bike by the way - did 46 miles yesterday and half of it was in the Cleveland hills which I couldn;t have attempted on a non-electric bike)

Mike

Here's an update. The hub drag problem on mine is getting worse. I rode around Kielder reservoir yesterday and only very occasionally was I able to put it into 'no assistance' mode. When I did, it was like the brakes being applied. At one stage I could barely pedal on level ground in 2nd gear at 8mph and even when the speed dropped to 5mph I could hardly move the bike forwards. On another occasion coming down quite a steep long slope I couldn't get to more that 17 or 18mph while pedalling (assistance off) and when I freewheeled I actually accelerated up to about 25mph.

The good news is that the electrical assistance was brilliant for the entire 30 miles around Kielder.

So passing Halfords Gateshead on the way back I called in and one of their guys tried it in no-assistance mode and said that despite him being an 'athlete' there was no way he could have pedalled the bike very far.

However, today when I took it back to the Halfords I bought it from, two of their staff tried it and claimed it was normal (it wasn't). So I then took their display model out and whilst it was considerably better than mine I could still detect the same problem with their bike. I think Suntour may have a batch problem and I also suspect this issue gets worse as mileage builds up. Mine has now done 270 miles and is pretty dreadful. Their demonstrator has done 30 miles and it's OK-ish.

Mike

May need new grease or lack of internal greasing and a service internally.

No brakes binding or axle over tight causing binding.

 

Any one brave enough to open theirs up to have a gander ?

If not send it to me to have a poke around however there is a disclaimer that I won't be held responsible if it didn't help to solve the issue or even turn again .

Edited July 5, 20187 yr by Nealh

May need new grease or lack of internal greasing and a service internally.

No brakes binding or axle over tight causing binding.

 

Any one brave enough to open theirs up to have a gander ?

If not send it to me to have a poke around however there is a disclaimer that I won't be held responsible if it didn't help to solve the issue or even turn again .

Thanks Neal - I may take you up on that eventually The bike is only two weeks old so new grease probably not required unless it was never greased properly in the factory.

Brakes definitely not binding - when it was happening I lifted the wheels and spun them and they spun freely. Axle could be overtight, but I don't see how that would make it OK sometimes and binding others.

Mike

Also might be an age thing and too new so not worn in yet.

My Bafang CST is a lovely motor now it has a good 4k+ miles on it, it is easier to ride unassisted then when new, It has had more grease added and new bearings, other wise internally all is original.

Thanks Neal - I may take you up on that eventually The bike is only two weeks old so new grease probably not required unless it was never greased properly in the factory.

Brakes definitely not binding - when it was happening I lifted the wheels and spun them and they spun freely. Axle could be overtight, but I don't see how that would make it OK sometimes and binding others.

Mike

 

Some hubs greasing is very sparse even from the factory.

Final update on this. Full marks to Halfords Hartlepool (in the end). They took my Crossfire back in and let me upgrade to a Crossfuse E (which has the Bosch Active Line Plus). They did all this within two days and when I went to collect the Crossfuse all my accessories had been swapped over. I think the staff there had been losing patience with what they should order to try and fix my Crossfire E.

And just to re-emphasise if your Crossfire e is (sometimes) very hard to pedal with the power off, it's not you, it's the bike - take it back and complain because I think they have a batch problem as their demo bike had the same fault.

Mike

PS 14 miles so far on the Crossfuse and hardly had to use the assistance

Anyone one else have a big issue with serious drag back from the hub with this bike? If doing about 16.5 /17.8mph on the flat I get a real drag/hub brake engagement. The harder I pedal the worse it gets. If I can get past this speed downhill, its fine. On a flat I'm stuffed. Why would it have such drag at this speed? I know they are limited but would expect the electric to cut out but not put the hub/brake/drag on to the extent that it I have to stop peddling and than wait to drop under 15mph before starting peddling again. Really getting on my nerves!

Drill a 3mil hole in the motor,fill with 100mils of grease then plug hole with a dap of silicone,

i used a 50mil syringe,

Drill a 3mil hole in the motor,fill with 100mils of grease then plug hole with a dap of silicone,

i used a 50mil syringe,

any chance of a youtube video, any particular part of the motor housing, what grease etc

I came across this article lately about an (older model?) Bafang/8Fun internal hub freewheel/clutch failure, with some photos of stripdown.

 

http://bruceteakle.blogspot.com/p/bafang-freewheel-failure-and-perhaps.html

 

http://bruceteakle.blogspot.com/p/blog-page_16.html

Edited August 13, 20187 yr by Sturmey

any chance of a youtube video, any particular part of the motor housing, what grease etc

any chance of a youtube video, any particular part of the motor housing, what grease etc

any chance of a youtube video, any particular part of the motor housing, what grease etc

Hi

I have a couple of photos for you, Give me a call if you like.

All the best

Drilling a hole in the hub may be good idea for greasing but best done worth hub open as you wouldn't want any pieces of swarf/filings in the hub to cause damage later down the line..

When I get a new hub I always open it and add grease if needed and screw it up just tight enough so I know it will come apart in the future when bearings/servicing may be required.

The Bafang/8funs & Yose are easy and with face plate mounting and only require 6 screws to remove.

Drilling a hole in the hub may be good idea for greasing but best done worth hub open as you wouldn't want any pieces of swarf/filings in the hub to cause damage later down the line..

When I get a new hub I always open it and add grease if needed and screw it up just tight enough so I know it will come apart in the future when bearings/servicing may be required.

The Bafang/8funs & Yose are easy and with face plate mounting and only require 6 screws to remove.

Drilling a hole in the hub may be good idea for greasing but best done worth hub open as you wouldn't want any pieces of swarf/filings in the hub to cause damage later down the line..

When I get a new hub I always open it and add grease if needed and screw it up just tight enough so I know it will come apart in the future when bearings/servicing may be required.

The Bafang/8funs & Yose are easy and with face plate mounting and only require 6 screws to remove.

Hi

Just seen your reply, Yes you are right about pulling the cover off befor drilling the hole in the hub,

Not sure how much crap went into the hub , I did used a vacuum when drilling as well,

Just me cutting corners,

At present all ok ,and at 18.st the little motor need some help.

All the best