super slim
Zen MBB Master
Most 142*12 DF road bike drive thru axle systems(174 mm long SRAM style with a triangle SS centering washer) use a 7005 Aluminium Drive side nut with a derailleur hanger bracket which is very strong(should be soft to protect the derailleur!), and stops the nut rotating!
https://www.ebay.com.au/i/143674088...2CRDUkkWnA0VyIFXSc0oOukLD3_UmztxoC4eUQAvD_BwE
This M12 1.75 mm pitch inside threaded part 19.3 mm long, in 7005 Aluminium, would have a M16 2.0 mm pitch external thread 6.3 mm long to thread into the fork, and be stopped from rotating with 2 off M4 grub screws and locking nuts. A 0.6 mm thick hard plastic washer, would reduce friction, so a higher clamping load could be achieved with a 2 off 2.9 mm dia. pin spanner.
https://www.mtbdirect.com.au/park-pin-spanner
A soft Aluminium Hanger bracket, and fork is clamped in position by the hollow double sided bolt, without relying on the Thru axle clamping load, as a cut out in the chain stay stops it rotating!
I have looked at a 174 mm long SRAM stealth style 142 m12 thru bolt with no washers, but I can only find ones with a triangle SS centring washer in Shimano style (M12 1.5mm pitch)
https://www.bike24.com/p2289997.html
A hard nylon triangle washer could be created on a 3D printer!
After seeing the photo by 3BS (which can not find now) of one of his low C/F bikes with a Cruzbike slider clamped to the top of the pivoting C/F frame, so the Slider sticks through the clamp , so a longer Slider can be used with the free length in a safe area, I was inspired to see how this could be used on a Cruzbike!
To do this, the Bottom Bracket needs to be welded to the Chain Stay, instead of the Steerer Slider tube, which would make the BB mounting a LOT stiffer.
On the Silvio V2.0 to 2.2, the external bearing housing collapsed due to the cycling pedalling forces going through the thin bearing housing into the Chain Stay, and could only use 1 off M5 clamping bolt to limit the crushing load on the external bearing housing.
On the Silvio V1.0, and then the S40, the Chain stay clamps went onto the stiff BB, and used 2 off M5 bolts.
If the chain stays could be ovalized near the BB, then the steerer slider tube clamp could clamp onto the BB instead of the external bearing housing, so the hand pulling loads (1/3rd of leg loads!) during sprinting, or hill climbing, would go directly into the BB!!!
The handle bar position is very close to the original curved slider attached to the BB!
See the two drawings of an original S2.2 with a 100 mm chainstay extension, and the proposed straight slider tube passing over the BB.
A 3D printed end cap would stop the Slider tube from collapsing due to clamping loads, and allow Shimano wired derailleur wiring to exit.
The pointed cone could be replaced with a Horizontal 25 mm dia tube 40 mm wide supported by two side plates, for a Light or a camera in a more aero position!
This double clamp uses 2 off M5 bolts for the Slider tube, instead of the 1 off M5 for the sliding inner (40.9 OD 2.43 mm wall, welded to the BB) and outer (44.2 OD 1.76 mm wall, welded to the Handle bar clamps) tubes clamp, which I have had to drill out the Aluminium thread and file a flat, so I could use a SS m5 nut to increase the clamping load, as this joint slipped a lot, when I was starting, but not the 2 m5 bolt clamp at the Steer to the Slider joint!
I have included a proposed removal stiff rear end, using the C clamps from the Silvio V2.0, but the clamp part welded to the tubular stays, as both approx. the same thickness.
I hope this creates a bit of discussion!!!
If anyone wants the autocad .dxf or .dwg file, please send me a personnel note, with your email address.
https://www.ebay.com.au/i/143674088...2CRDUkkWnA0VyIFXSc0oOukLD3_UmztxoC4eUQAvD_BwE
This M12 1.75 mm pitch inside threaded part 19.3 mm long, in 7005 Aluminium, would have a M16 2.0 mm pitch external thread 6.3 mm long to thread into the fork, and be stopped from rotating with 2 off M4 grub screws and locking nuts. A 0.6 mm thick hard plastic washer, would reduce friction, so a higher clamping load could be achieved with a 2 off 2.9 mm dia. pin spanner.
https://www.mtbdirect.com.au/park-pin-spanner
A soft Aluminium Hanger bracket, and fork is clamped in position by the hollow double sided bolt, without relying on the Thru axle clamping load, as a cut out in the chain stay stops it rotating!
I have looked at a 174 mm long SRAM stealth style 142 m12 thru bolt with no washers, but I can only find ones with a triangle SS centring washer in Shimano style (M12 1.5mm pitch)
https://www.bike24.com/p2289997.html
A hard nylon triangle washer could be created on a 3D printer!
After seeing the photo by 3BS (which can not find now) of one of his low C/F bikes with a Cruzbike slider clamped to the top of the pivoting C/F frame, so the Slider sticks through the clamp , so a longer Slider can be used with the free length in a safe area, I was inspired to see how this could be used on a Cruzbike!
To do this, the Bottom Bracket needs to be welded to the Chain Stay, instead of the Steerer Slider tube, which would make the BB mounting a LOT stiffer.
On the Silvio V2.0 to 2.2, the external bearing housing collapsed due to the cycling pedalling forces going through the thin bearing housing into the Chain Stay, and could only use 1 off M5 clamping bolt to limit the crushing load on the external bearing housing.
On the Silvio V1.0, and then the S40, the Chain stay clamps went onto the stiff BB, and used 2 off M5 bolts.
If the chain stays could be ovalized near the BB, then the steerer slider tube clamp could clamp onto the BB instead of the external bearing housing, so the hand pulling loads (1/3rd of leg loads!) during sprinting, or hill climbing, would go directly into the BB!!!
The handle bar position is very close to the original curved slider attached to the BB!
See the two drawings of an original S2.2 with a 100 mm chainstay extension, and the proposed straight slider tube passing over the BB.
A 3D printed end cap would stop the Slider tube from collapsing due to clamping loads, and allow Shimano wired derailleur wiring to exit.
The pointed cone could be replaced with a Horizontal 25 mm dia tube 40 mm wide supported by two side plates, for a Light or a camera in a more aero position!
This double clamp uses 2 off M5 bolts for the Slider tube, instead of the 1 off M5 for the sliding inner (40.9 OD 2.43 mm wall, welded to the BB) and outer (44.2 OD 1.76 mm wall, welded to the Handle bar clamps) tubes clamp, which I have had to drill out the Aluminium thread and file a flat, so I could use a SS m5 nut to increase the clamping load, as this joint slipped a lot, when I was starting, but not the 2 m5 bolt clamp at the Steer to the Slider joint!
I have included a proposed removal stiff rear end, using the C clamps from the Silvio V2.0, but the clamp part welded to the tubular stays, as both approx. the same thickness.
I hope this creates a bit of discussion!!!
If anyone wants the autocad .dxf or .dwg file, please send me a personnel note, with your email address.
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