Can I fit front the brake calliper and custom rear wheel spacers? Project Bike Build -Part 25
Following on from successfully truing the brake disc, I move towards fitting the calliper and the newly custom rear wheel spacers to my Scrambler bike project based around a CB250T Frame and Engine.
Good day Ryan, in the last video's comments you said it was only going on slow trails, but in this video you say you are going for daytime running, which I take to mean a daytime MOT. Is this correct? If so, you may not have trued the front rotor to a standard that will pass. 0.2mm is way beyond the service limit and has many negative implications on your bikes stability and braking ability. If your brake lever pulses under braking you will have to work to tighter tolerances. I am also concerned about how you're mounting the caliper. Please make friends with a local engineer.
Hey Ryan, good to see you continuing with the xl/cb . On the calliper normally ( im sure there are exceptions but ive never seen one) the centre line of the calliper lines up with the centre of the disc. Most are two piece split callipers and are designed where lining up the join with the disc centre allows the exact travel on the pistons pads and sliders. Even with non sliding callipers the centre line is the same . And on a one piece type there will be a guide mark to centre on the disc. So basically line up your calliper centrally with your disc and then adjust the mount and spacing accordingly. Apologies if this is already obvious to you. Great video buddy , thanks! Peace and love brother as always ✌️ ❤️
Easiest way to work out spacer size needed for front caliper is to stack washers until you get the right offset, then measure total thickness for your spacer size. The larger the outer diameter of your spacers the better, as they will be more stable. One important thing is to use the right grade of mounting bolts – do not under any circumstances use stainless bolts, they are nowhere near strong enough. I would recommend 12.9 grade as opposed to the standard 8.8 (this will be stamped on the head of most standard grade hex head bolts). As a rule, cap screws (allen bolts) are made from 12.9 high tensile steel as standard, so that is what I would recommend.
Ryan as long as you get your spacers welded onto the back plate and use hardened shouldered bolts that brake should be fine. Most of the braking force is going to rotational anyway pushing in the direction of wheel travel. Personally i would not reinforce the plate it looks heavy enough guage to me. And as an engineer with 30 years experience i would like to think i would be right enough 😊
You really want to use some cutting fluid when tapping also it didn't look quite true/square (maybe just camera angle?), to tap true, if you have a pillar drill you can put the tap in the chuck and rotate by hand to start it then continue in the vice. I would not worry about welding spacers to the plate, just use some good aluminium spacers, after all your forks are aluminium! Your fixing bolts (of the correct size & type) will hold them in place. You have a floating calliper so position centrally as already mentioned. Don't worry about frame being dirty/unfinished, your doing it the correct way… Dry build first, strip, do finishes, rebuild. Coming along nicely!
8 Comments
Good to see you got that rear wheel all sorted Ryan, bikes looking great so far
Good day Ryan, in the last video's comments you said it was only going on slow trails, but in this video you say you are going for daytime running, which I take to mean a daytime MOT. Is this correct? If so, you may not have trued the front rotor to a standard that will pass. 0.2mm is way beyond the service limit and has many negative implications on your bikes stability and braking ability. If your brake lever pulses under braking you will have to work to tighter tolerances. I am also concerned about how you're mounting the caliper. Please make friends with a local engineer.
Hey Ryan, good to see you continuing with the xl/cb .
On the calliper normally ( im sure there are exceptions but ive never seen one) the centre line of the calliper lines up with the centre of the disc. Most are two piece split callipers and are designed where lining up the join with the disc centre allows the exact travel on the pistons pads and sliders. Even with non sliding callipers the centre line is the same . And on a one piece type there will be a guide mark to centre on the disc. So basically line up your calliper centrally with your disc and then adjust the mount and spacing accordingly. Apologies if this is already obvious to you. Great video buddy , thanks! Peace and love brother as always ✌️ ❤️
Easiest way to work out spacer size needed for front caliper is to stack washers until you get the right offset, then measure total thickness for your spacer size. The larger the outer diameter of your spacers the better, as they will be more stable. One important thing is to use the right grade of mounting bolts – do not under any circumstances use stainless bolts, they are nowhere near strong enough. I would recommend 12.9 grade as opposed to the standard 8.8 (this will be stamped on the head of most standard grade hex head bolts). As a rule, cap screws (allen bolts) are made from 12.9 high tensile steel as standard, so that is what I would recommend.
Ryan as long as you get your spacers welded onto the back plate and use hardened shouldered bolts that brake should be fine. Most of the braking force is going to rotational anyway pushing in the direction of wheel travel. Personally i would not reinforce the plate it looks heavy enough guage to me. And as an engineer with 30 years experience i would like to think i would be right enough 😊
👍🏍
You really want to use some cutting fluid when tapping also it didn't look quite true/square (maybe just camera angle?), to tap true, if you have a pillar drill you can put the tap in the chuck and rotate by hand to start it then continue in the vice.
I would not worry about welding spacers to the plate, just use some good aluminium spacers, after all your forks are aluminium! Your fixing bolts (of the correct size & type) will hold them in place.
You have a floating calliper so position centrally as already mentioned.
Don't worry about frame being dirty/unfinished, your doing it the correct way… Dry build first, strip, do finishes, rebuild.
Coming along nicely!
A milestone indeed , looking good and so much yet to come 👍