March 11, 20179 yr Hey so basicly im not convinced the 250W cyclotricity fronthub kit is actually 250w. The motor runs up to 20 mph on setting 5 and it destroyed my alluminium fork in less than 2 weeks. With this in mind I am now in search of a new 700c steel fork that can handle potentially 350W/500W in the front. It could still be 250W but it destroyed my front fork very fast, I wasn't even riding it that much. I have V brakes and am not skilled enough to install discs (V brakes are still a challenge for me). Ideally I want a fork that is strong enough even without the torque arms (I will still be installing the torque arms but you get the idea). I could switch to calipers but I really dont think they are strong enough for an ebike. My bike is a specialised sirrus which uses a standard threadless headset.
March 11, 20179 yr The reason that the kit destroyed your forks could have been that it wasn't fitted properly. There's a few things you have to look out for. Having said that, some 700c alloy forks are a bit on the weak side. Before we can advise, we need to know whether 1" or 1 1/8" .
March 11, 20179 yr I have had 350w bpm in Suntour 700c sus forks for about 1900 miles and had no issues, the drop outs were quite meaty. The axle needs to be a snug fit with virtually no play and usually require some more of the drop out area to be reamed out to allow the axle to sit deeper. Show some pics of the damage.
March 11, 20179 yr I've been running an Ezee front hub in Suntour NVX fork for about 3000 miles now. No problems at all, but I do have a torque bracket fitted.
March 11, 20179 yr Author I have 1 1/8 threadless fork. I didnt fit it the guy in the LBS did, ill probably fit the next one myself. Are steel forks strong enough to survive if they are not installed properly? In regards to the torque arms are they meant to face up into the dropout or can they just sit in the dropout facing down?
March 11, 20179 yr I have 1 1/8 threadless fork. I didnt fit it the guy in the LBS did, ill probably fit the next one myself. Are steel forks strong enough to survive if they are not installed properly? In regards to the torque arms are they meant to face up into the dropout or can they just sit in the dropout facing down? Sounds like you are talking about the AR (Anti rotation) washers with the little right angle tab on them that sit in the dropout, they alone won't stop any axle rotation. You need to supplement these with an added TA (Torque arm) or 2 which sit snuggly over the axle before the axle nut then are secured to a fixed point on the forks. This can be a spare threaded hole, a bracket from a brake disc set up or a P clip arrangement. How the AR's sit in the drop out depends on how much meat there is in the fork to accommodate them, my ones fit facing up and sit nicely in the drop out recess. Edited March 11, 20179 yr by Nealh
March 11, 20179 yr It's very difficult to bust steel forks, but the metal can bend instead if it's too thin. The thing to look for is the drop-outs being on the inboard side of the tube so that the tubes don't rub on the motor. these look OK if you're happy with rigid ones. Don't worry about the thread. You can still clamp on it. The steerer looks so long that you'd probably want to cut off the threaded part anyway.: http://www.ebay.co.uk/itm/MONGOOSE-700C-HYBRID-BIKE-FORKS-BLACK-V-BRAKE-1-1-8-THREADED-NEW-FREE-P-P-/262855876103?hash=item3d336e5e07:g:SekAAOSwB-1YpYfp If you want suspension, there's these ones, but they have the drop-outs in the middle. You'll be alright on the disc side as long as you don't have a disc, but I can't say about the other side. I think it'll be OK because the tubes are thin. You'd probably just get clearance with maybe an extra washer on the axle: http://www.ebay.co.uk/itm/INSYNC-700c-SUSPENSION-BIKE-FORKS-Vbrake-150mm-threaded-1-1-8-Steerer-SILVER/171444141052?_trksid=p2047675.c100005.m1851&_trkparms=aid=222007&algo=SIC.MBE&ao=2&asc=20140122125356&meid=dd0e2b67fb6343618a636525b324c4ff&pid=100005&rk=2&rkt=6&sd=232202783263 You need a star nut if you buy threaded ones. http://www.ebay.co.uk/itm/Bike-Headset-Double-Flanged-Star-Nut-for-1-1-8-Steerer-Gift-/371842414381?hash=item569388f72d:g:TBUAAOSwZQRYdfjJ
March 11, 20179 yr This is a torque arm: And this is an anti rotation washer: http://translate.google.co.uk/translate?hl=en&sl=de&u=http://www.ebike-solutions.de/de/Shop/Motoren/Drehmomentstuetzen&prev=/search%3Fq%3Dhttp://www.ebike-solutions.de/de/Shop/Motoren/Drehmomentstuetzen%26hl%3Den%26biw%3D1440%26bih%3D739
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