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    Yeah... I am allergic to pain... I can just imagine how much skin would be removed if one was travelling on a bitumen street at 35 mph and grab a hand full of front brake, and the front wheel folds under and one slides down the pavement on one's face Click image for larger version

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      All of my threads are chronological. That first front end is a DNM-USD-8 and I was able to fit a dual disc brake setup on it. That front end was a medium priced unit and maximum tire width was maybe 3.0 inches. I have had such good luck with the Maxxis Mammoth tires that I wanted a pair on the bike. DNM makes a triple crown fat fork but because of the supply chain problems this year I couldn't find one.

      I did find a Rockshock Bluto for less than $450. The Rockshock is a better fork than the USD so I am not worried about it folding on me.

      You guys like to talk about speeds of 30 and 35 mph and while this is doable it is not the norm. Ebikes really shine around 20 mph. It is nice to have a bike that can do 40+ but most of the time my average speed comes in between 15 and 20. I went 35 miles today and used less than 19 watts per mile. This was a combination street off road and bike path.


        Yes hopefully the engineers are taking into account the different forces on a fork from disc brakes. At least in the old days the counter braking force was near the headset so not likely a huge factor to keep in mind compared to what the now slowing wheel was doing to things. Now you put the disc in the mix (and or a hub motor) and you got a whole new set of forces to consider not to mention more available braking. I'm sure tires are better now too. 30 years ago it wasn't a big deal, the brakes don't grab that well and if they did the tires wouldn't have much traction so no big deal to the fork and frame.


          I have been searching for threads on forks and failures but can't find anything? Does anyone have any links to anything fork related?

          I personally will stick with triple clamp style forks on anything fast and heavy... I don't think the type of brakes makes any difference to the bending moment of the bicycle type forks... whether the brakes are disk or V brakes, the slowing of the wheel still acts on the axle just the same... and the end of the fork which is essentially an unsupported cantilever where all of the stresses act on the single tube at or just below the bottom bearing... even though triple clamp forks can and do break, I believe they wont break as suddenly and completely because the two independant fork legs are supported in 2 places so the bending moment is spread over a wider area. That is my uneducated guess anyway

          I have been involved with gyrocopters for many years, having built and flown many... so, I am used to looking at things like nose wheel forks and where the stresses and strains act. My advice to myself and others is to do a 'preflight' on one's ebike and just check there is no bending happening nor cracks beginning anywhere from the front of the frame (especially at welds or the parent metal next to a weld) where the steering tube attaches and the forks themselves suffer the most bending/stress.

          I know, I know... a bit pedantic... but as I say, I am allergic to pain. It can't hurt to check Click image for larger version

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            The bike that my enduro replaced is an Electra fat cruiser that I converted.

            That is a factory front fork that I added a 203mm rotor and an avid BB7 mechanical caliper to. That fork felt weak on hard braking. If I had a hydraulic system I think i could have bent it.


              I actually went to that bike shop again today, those forks i got (Zoom) have a 20mm thru axle... I was asking if I can buy a 26" front wheel with a 20mm thru axle with an inch or inch and 1/4 rim and disk compatible hub... I may have been asking for a veloca-raptor's eye tooth... the people running the bike shop seem to only be interested in the latest mountain bikes or something?

              I did look at some of the forks on the bikes they had there... most have the steering neck with the bigger bearing at the bottom... like a flared neck... they look like they could deal with the braking forces a bit better than the normal forks with the same size bearing top and bottom.

              If I can find out where to buy rims and hubs, I will have to make the wheels myself. It is hopeless trying to make anything that is not 'main stream' and very hard not to mention anything to do with ebikes,,, I am thinking I might turn down some alloy bar to make adaptors for the 20mm fork leg pinch setup... then fit the front wheel with a long thru bolt (thru the adaptors) then pinch them up.

              Calfee, I really like that cruiser... do you still have/use it? Or did you use components off of it for your new enduro? I couldn't choose which to have between the cruiser and Enduro... I would have to have one of each I'm afraid Click image for larger version

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