Originally Posted by
cat0020
There are a few ways to extend the steertube for mounting different stems on the particular ENGWE ebike, I've tried a several, still trying to finalize the most secure way for myself.
I think the method Gearbasher used is fine, as long as the top cap keeps a decent amount of tension on the whole setup.
I've also tried the hidden same hidden stem extender, it is made of aluminum, the center bolt is aluminum, too.. easily stripped when you try to torque it down. Also it is more difficult to have proper tension for it to secure the headset without a top cap that's threaded.
I currently have this steertube extender installed, easily combined with different MTB stems, not the lightest setup, but with a top cap and long bolt to use existing star nut in the steertube: :
https://www.ebay.com/itm/154650501497
If I ever find an aluminum BMX high rise handlebar, I'll probably go with something similar to gearbasher's setup; I don't think it's anymore dangerous than other setups for my riding; that's just me.
I figgure if I split the difference between the existing steering tube and the extender with the stem mounting bolts it should be as safe as it will get. Both bolts will have something to clamp to. I figgure a 3mm headset spacer below the stem, then the stem, then put two 3mm and a 10mm headset spacers on top of the stem should leave a 3mm space for the top cap to set the headset tention. My available length of steerer tube is 21mm and the extender is 30mm for a total of 51mm. The total stackup of spacers and stem will be 54mm. So from the dust cap to halfway of the stem will be 20.5mm.
My only concern will be getting the expander tight enough. I think some removable loktite might be a good idea. Might scuff up the conical washer on the bottom end for better grip. Not sure if the conical washer will want to spin. Spec says "
All accessories are made of 7075 aluminum alloy, which is lighter and stronger than 6061. 7075 is the lightest and strongest aluminum alloy".
https://www.ebay.com/itm/154650501497 I'd like to use this but I don't have enough steerer tube for both bolts to compress on. What was your steerer tube length and does both boths compress on it or is it just the bottom bolt? With the shape of it maybe the bottom bolt is enough?
Like I said I just use it to ride around a sporting clay course on a flat gravel path. No hills, no jumps, no 18 yead old mountain trail crazy gettin air stuf. I'm 66 years old, thats how I ride lol.
If all else fails I may have to do the okie quill extender thing.