First attempt ebike conversion

[markkg]

Looking for a bit of help please, just finished fitting 1000w rear drive kit to Carrera Vengeance MTB. All went pretty smoothly, tested it on the ground and all seemed ok. As soon as I put the bike on the ground and hit the power button the rear wheel immediately jumped out of the frame, after a second attempt with the same issue i had a look and it seems the frame dropouts are very shallow, could this be the cause and if so is there a remedy, or am I doing something wrong.
Any help appreciated, I’ve attached a couple of photos.

 

[RobN]

Did you not get any torque arms with the kit?
And there is usually some special shaped washes to help it stop spinning out as well.

 

[markkg]

Yes i fitted the washer with a tag which slots into the drop out on both sides.

 

[markkg]

Just been looking at torque arm kits on Amazon as nothing was with the kit, do you think this is the issue.

 

[RobN]

I would say no torque arm on is certainly a problem so definitely get one on , or two. I believe it can rip the wiring harness out as well if it spins out of so be careful with it.

 

[Nealh]

The axle on the RHS is certainly not sitting deep enough all of the flat area of the axle needs to be held so you have some filing to do, tab washers for those 1kw cheap hubs are not enough and you will need as least one torque arm fixed securely.
Not only will you have file out the derailleur hanger, the bikes drop out will need doing as well. On the hanger side you can clearly see a gap/daylight between the axle and the D/O seat area, carefully file the corners so that the axle sits down tight.
Also you may have to file the LHS another 1 -1.5mm so the motor sits horizontally level.
You are lucky if the motor wire wasn't damaged ?

 

[RobN]

Also the tag on the washer I think should be at the open end of the drop out. I cant see the tab on yours so is it on the wrong way round and maybe not letting the axle seat in far enough?
Others on here may be able to clarify for you. Put some more pics of washer in situ so you can get more advice on correct fitment.

 

[markkg]

I would say no torque arm on is certainly a problem so definitely get one on , or two. I believe it can rip the wiring harness out as well if it spins out of so be careful with it.

Just ordered two so hopefully that does the trick.

 

[markkg]

Also the tag on the washer I think should be at the open end of the drop out. I cant see the tab on yours so is it on the wrong way round and maybe not letting the axle seat in far enough?
Others on here may be able to clarify for you. Put some more pics of washer in situ so you can get more advice on correct fitment.

This was the set up I had which I thought was correct ?

 

[markkg]

The axle on the RHS is certainly not sitting deep enough all of the flat area of the axle needs to be held so you have some filing to do, tab washers for those 1kw cheap hubs are not enough and you will need as least one torque arm fixed securely.
Not only will you have file out the derailleur hanger the bikes drop out will need doing as well.
You are lucky if the motor wire wasn't damaged ?

It literally came straight off so the wiring looks ok. Wow I wasn’t prepared to start modifying the frame there doesn't look like there is much to file its so thin anyway.

 

[Nealh]

Check the axle size as you likely need 14 x 10 T/A's.

 

[Nealh]

It literally came straight off so the wiring looks ok. Wow I wasn’t prepared to start modifying the frame there doesn't look like there is much to file its so thin anyway.

In that case the D/O's aren't suitable nearly all bikes need some modifying at the rear for hubs to sit in correctly more so with the cheap D/D hubs with the 14mm axle depth.

 

[sjpt]

This was the set up I had which I thought was correct ?

You can see in those pictures that the tab wasn't engaged in the drop out slot. The drop out slots must be very short. The torque arms should sort it anyway.

 

[Nealh]

This was the set up I had which I thought was correct ?

Sorry but Installation is poor the tabbed washers are doing nothing, the tab needs to physically hold in the D/O as well as having at least one TA fitted if not two.

 

[markkg]

Check the axle size as you likely need 14 x 10 T/A's.

The axle is 210 x 10 according to the manual, what are 14 x 10 T/A’s excuse my ignorance.

 

[markkg]

You can see in those pictures that the tab wasn't engaged in the drop out slot. The drop out slots must be very short. The torque arms should sort it anyway.

Thats good news I will try the torque arms first as I really don’t fancy modifying the frame if I don’t have to. The drop out slots did look shallow but I wasn’t sure.

 

[Nealh]

It literally came straight off so the wiring looks ok. Wow I wasn’t prepared to start modifying the frame there doesn't look like there is much to file its so thin anyway.

The reason the hub wheel cam straight out is there is nothing to hold it properly in the D/O's, you are trying to replace a 9mm QR axle with a 14mm one. That means axle seat needs to be at least 2.5mm deeper if not more.

 

[Nealh]

The axle is 210 x 10 according to the manual, what are 14 x 10 T/A’s excuse my ignorance.

Measure the hub axle it will be 10mm wide x 14mm deep, not interested in the 210mm over D/O width. All of the flat area you can see needs to be held within the drop out even with TA's.

 

[markkg]

The reason the hub wheel cam straight out is there is nothing to hold it properly in the D/O's, you are trying to replace a 9mm QR axle with a 14mm one. That means axle seat needs to be at least 2.5mm deeper if not more.

Ok thanks for the advice I guess I am ordering a decent file then at least its aluminium so a bit easier to file.

 

[vfr400]

Thats good news I will try the torque arms first as I really don’t fancy modifying the frame if I don’t have to. The drop out slots did look shallow but I wasn’t sure.

Your axle is 14mm diameter milled down to 10mm across the flats, so you need 14mm x 10mm slots in the torque arms. the other size is 12mm x 10mm, which won't fit your axle.

I'd be filing the drop-outs deeper. If you look at the centre of your axle, it's now about 4 or 5mm further down than the original 9mm one's centre. That can affect the position of the brake pads on the disc.