Fork ends have started to open.

[onespeed]

I have 2 bullitts. One came with ezee conversion setup with a Grin torque arm - 1500w was the top output and it had no problem using just the 1 torque arm. The other I installed a crystalyte setup running a 60v battery - it spits out 2200watss off the line.

For the 2nd I mimicked the setup on the first one and installed a torque arm. I found out within a month that the power output overwhelmed the single torque arm and pretty soon the axle jumped out of the fork ends after the non torque arm side spread out. I had another torque arm sitting around so I installed it on the other side. I marked the meeting points with a sharpie and check them all the time - no movement.

I am swapping out the lower powered setup on the 1st bullitt and noticed there is minimal spreading of the fork ends on each side. The system has had a motor since before I bought it - not sure how long it had been installed. I did the same thing with the new setup and installed torque arms on each side - GRIN. Everything seems to be held in place with snugging down the bolts/washers and the torque arms on each side.

What risks am I running here - if any? I have been using the double torque arm setup on a very powerful motor for 4 months now with no visible movement when the markings are checked. I am running the system industrially, delivering beer for work - so lots of weight with beer, costco runs and laundry.

 

[99t4]

Good clear photos would help us formulate better advice for your situation.

 

[LewTwo]

High powered motors are NOT recommended for front forks.

 

[neptronix]

Pictures would help a lot.

If the dropouts are ruined from insufficient clamping of the motor then they are not contributing to holding the wheel; watch for things like the axle surface gradually getting rounded by the torque arms themselves, because those are likely to be the only thing supporting the motor at this point.

I personally wouldn't run anything above 750W without two torque arms that have <1mm of total movement.

 

[onespeed]

The bullitt that I have the 2 torque arms on now has held fine for the last 4 months. No discernible movement or continued spreading of the fork ends - I have been checking the marks on the regular. The axle is not rotating forward, the t-arms are doing their intended job.

I would know immediately if there was some movement because the disc alignment would be off and the screeching/scraping would happen just moving. I changed the pads yesterday and the wear is fairly even on both sides - nothing I havent noted before when swapping pads when I was running a lower rated motor.

 

[neptronix]

If that's the case long term then i wouldn't worry.
If you had >3000w flowing through that motor then i'd be more concerned.