Schmolke M5x40 carbon bolt
Schmolke Carbon Screws
The screws are manufactured in a highly specialised pressure extrusion procedure. The material used is high quality Intermediate module fibres with PEEK-matrix.
This is the only means to make sure the fibres are arranged in a spiralling pattern following the thread and centred towards the inside of the screw. The actual thread can not be stripped. In terms of dynamic strength carbon fibre is much superior to all other materials used for screws. They are stronger and 40% lighter than aluminium bolts.
General assembly instructions of Carbon Screws:
Carbon screws do not need to be tightened up as much as metal screws, they expand more when tightened, and hence they are less likely to become loose. Since they also suffer less from friction in the threads they do not need to be tightened with as much torque as a metal screw to achieve the same internal tension. If you further want to increase internal tension without raising the torque add grease to the thread and the bottom of the screw's head.
Where to use Carbon Screws
Bottle cage
Carbon screws are perfectly suitable for mounting bottle cages. Usually this requires M5x20 hex screws. Some models, such as BTP or Tune, may require M5x20 screws with a countersunk head. Carbon screws may also be used for blanking off bottle cage threads, which are not currently required. In this case you may shorten M5x20 hex screws to a thread length of 7mm.
Headset adjustment screw Ahead cap
Carbon screws are perfectly suitable for adjusting the headset. Usually this requires a hex M6 screw. These can often be shortened to save yet even more weight. Make sure the screw is long enough to use the full length of thread of the insert in the fork tube. Some Ahead caps may require an M6x16 screw with a countersunk head.
Brake levers and shifters MTB
Carbon screws are perfectly suitable for mounting brake levers and shifters on your MTB. Usually this requires M5x20 screws. Please check what exactly you need before buying though. Screws may have to be shortened to the length of the original screws.
V-Brakes rear
Carbon screws are perfectly suitable for mounting the rear brake of your MTB. Use your original screws as a reference for shortening M6x30 screws. We recommend using a washer to ensure the brake’s function. Do not use carbon screws for front brakes or disc brakes. Failure may lead to injuries.
Use common sense when shaving weight off your bike!
Road brakes
Carbon screws are perfectly suitable for mounting the brake pads to the brake bodies. Use your original screws as a reference for shortening M5x20. Make sure the screw’s head is large enough to clamp securely. If in doubt use a washer.
Adjustment screw for bearing play THM Clavicula crank
M6x16 carbon screws with countersunk head are perfectly suitable for adjusting the side play of the bottom bracket bearings.
Front derailleur
Depending on the make and model you may be able to use up to 4 carbon screws:
1. With most derailleurs you may use M4 screws to close the cage.
2. For front derailleurs you may use M5x20 screws for the mounting of the derailleur to the frame.
3. With Campy derailleurs you may replace the centre screw of the parallelogram with a M4x16 screw.
All carbon screws should be shortened to the original screws’ length.
Rear derailleur
You may use a fair number of carbon screws on all derailleurs:
1. Axle bolts of jockey wheels
2. Swing stop screws
3. Adjustment screw (screw against the frame’s derailleur eye)
You may use carbon screws to clamp the shifter cables. Please be aware, that the screws’ heads are likely to wear with use, and that they may have to be replaced then.
Important Notice:
Never use carbon screws on connections with high load (bar, stem, seat post), or those demanding high torques (brake caliper, bowden cable)!
Professional cutting carbon screws:
- 1: Screw two fitting nuts downt to the head of the screw and interlock them.
- 2: Place the screw into a vice (never clamp carbon itself!)
- 3: Cut the screw down using a special carbon saw, or a new metal saw blade. Avoid too much pressure. Leave the screw at least 1mm longer than desired.
- 4: File down the rest of the way, parrallel to the head, using a type 3 flat-file.
- 5: Screw off the first nut. If it goes down gently, remove the second nut also, if not, redo the filing at the cutting edge.
- 6: The screw is ready to be used. Mind the appointed torque and only use fitting, not outworn tools.