Alrighty then. More time in on getting the dual disk conversion done and I am an idiot - thus the thread title. Why aren't you guys looking out for me when I do these things? I mean, is it too much to ask for a heads up when I do something stupid?
It seems that I was 180 degrees out of whack with the FAQ... somehow. Still not sure but I think I'll work it out here for the benefit of anyone else that can't follow instructions. Step by step.
Tools & Parts Needed:
1x calliper arm
1x calliper
1x disc
6x8mmx110mm bolt (for disc)
1xlower brake line (that makes two all up)
1x steel brake line to calliper (which again makes two all up)
1xdouble banjo fitting (for the two lower brake lines)
1x bigger master cylinder (some say GL goldwing master cylinders are ok. I used one off a modern dual disc bike.)
1x CB500/550 speedo drive plate (no modification)
2x6mmx30mm bolts and washers
1x8mmx35mm bolt and washer
Check - minus the 500/550 speedo drive plate which is the same as the 750. You'll need to saw off the bell and find a way to get the tangs bent down in a nice straight bend. I got a machine shop to do the bending and even then had to Dremel the inside of the bend square to the hub.
OK for starters, put the bike on the centre stand, and jack the front off the ground, take the wheel off, remove the axle and the factory disc bolts.
Check
Remove the speedo drive,chrome retainer plate,speedo gearbox drive, and the rubber ‘O’ ring on the hub.
Now get your two discs... when you look through them back to back, they will line up, but only on a couple of spots, mark them so when you bolt them together on the hub, they will look the same when looked though; this is just cosmetic, but I am fussy with stuff like that and its easier to do it now then when you get it all back together and realise...!!!.
Right. Now that you have made sure they line up, and have marked them, get the 6, 110mm long bolts and pass them through disc number one. This disc is going onto the speedo drive side. If you put them in from the other side the nuts will hit the speedo gear box, so bolt heads MUST be on the speedo side(fig 1). Now feed the disc over the hub, with the bolts going right through the hub, and put disc number two on, with holes that were marked lined up, and do up the nuts. (Sorry I couldn’t find a torque setting for these bolts.)
Checkity check and damned if I know the torque either. Try really super tight.
Now put the CB500/550 speedo drive plate in the middle of the second disc, it should be a really neat [tight] fit, but it should fit, you wont be able to use your chrome dress ring - no room. Next put your speedo gearbox on, then refit your axle. If you have forgotten which side the shaft goes into, it insets from the speedo side, once this is done, your front double disc wheel is complete. Now the caliper.
Still not a 500/550 speedo drive but I'll get over that. Should work something like this
Now you are going to have to refit the wheel for this; from now on it is a lot of fitting, and removing of the caliper arm to get right.
Firstly I fitted the caliper arm, and didn’t check anything. BIG mistake! What happened was, when I squeezed the front brake the caliper wasn’t parallel to the disc, and jammed the whole show up!!! I mean major drama just to get the caliper mount bolts undone so I could just move the bike.
So what you need to do is place the 8x35mm bolt and washer into the lower hole on the caliper pivot arm and just nip up. This will give a good idea of how out of shape the mounts on this fork leg are. Mine had a gap of more than 20mm between the top mounts on the fork to the top mount of the pivot arm.
Now this is where the patience and trial and error are coming into there own. You need to take the pivot arm off again, and file the lower mount little by little till you can mount the pivot arm parallel to the disc(fig 2), you can use a straight ruler along the side of the pivot arm to check parallel.
Now what I did was try and file the lower mount as close as I could to the fork leg, without fouling up the pivot arm, before I started shimming the top of the mount. (fig. 3)
Here's where things go wrong for me. I read this and fitted it up and concluded I needed to bring the lower mount in to match the original. A quick pictorial recap:
The factory machined fork turned around and fitted to the left (looking at the front of the bike)
The lower mount lines up nicely with the rotor.
What's happening on the unmachined right side fork? Why, it's just about 20mm longer than the left.
Let's file the bejeezus out of it! Well, no. That would be wrong. But it's what I did.
I think I read and didn't understand
Mine had a gap of more than 20mm between the top mounts on the fork to the top mount of the pivot arm.
Reading it again I'm still not sure I understand the "top mount of the pivot arm" There's three holes. I think I'll call mine top and bottom.
So damage done. Let's soldier on.
This took some time to get right, because you have to file the pivot mount parallel to the disc as well, otherwise the top of the pivot arm won't mount to the fork. Take your time; you can always take metal off - its bloody hard to put it back on though, and also remember that there are metal filings going into the threads - blow these out before screwing a bolt into them otherwise it will destroy the thread, and that’s not a good thing.
Awesome point. Pretty sure I would have caught the filings since they had completely filled the hole of the bottom mount but still... awesome point.
Next, when things are parallel, nip the pivot arm to the fork leg, then measure the gap left between the top mounting points of the fork and the top mounts of the pivot arm, and then file back a pair of washers to fit in these gaps ,in (fig. 3) you see the rear mount shim, and in (fig. 4) you see the front mount shim.
You will also notice how parallel the caliper pivot arm and the disc are, this is essential to this set up working properly.
So, you've read this far. You know I'm an idiot but here's what I ended up doing based on a conversation here on just how to tighten up the hex head bolts on the back of the calipers once the arm is in place.
The answer is you don't. You assemble the caliper and hanger as a piece and bolt it to the fork leg. Which is where I got the idea to do just that and use it as a guide for where the damn hanger should be positioned relative to the fork leg so it'll be perfectly parallel.
Basically, fit the caliper over the rotor (mine have brand new brake pucks so it's tight) and take a peek at the gaps between the hanger and the fork. THAT is what needs to be fixed whether too tight or loose as hell. Mine, after taking the lower mount parallel to the rotor, was loose as hell. I was not pleased.
Back to the FAQ
Ok now we have the pivot arm all nice and parallel; you would have also noticed by now that you have to try and get the bolt done up when the wheel is on. Don’t uses socket head caps screws as the mounting bolts like I did - have you ever tried getting an allen key between a wheel to do them up!!! Stick to bolts for this application. Another thing - you are going to have to remove one of the calipers if you want to remove the wheel in the future since the wheel and tire just don’t fit between the two pivot arms when they are both bolted on. There is always a downside.
What? Stick to bolts? Uh... If yours is like mine just assemble the caliper and bracket and fit it up. Bolts? Really, I don't know squat but does that make sense? Would a bolt even fit in a k5 caliper with the heads recessed like they are?
Moving on:
Now, while looking at the bike from the front, mount the guard to the right side first using the bolts and washers that came off that side; on the left side use your 8mmx35 bolt and washer on the lower mount.
You will find at this point you may need to slightly bend your guard mount a little to get the pivot arm behind it (fig. 4). The guard has rubber grommets in it; take them out. Now you need 6mm washers between the guard mount and the pivot arm, and then you need 6mm washers between your bolts and the other side of the guard mount (the guard mount is sandwiched between the washers); this stops the guard from moving around and makes for a more solid plate form for you to tighten the upper pivot arm bolts.
Now you should have the pivot arm and the guard fitted and everything should still be parallel. Now to fit the adjuster screw, you will notice that the adjuster screw mount on the fork is in a different spot than the other fork which is why I put the lock nut on the inside; there just wasn’t any room on the outside. You will see this in fig. 4.
I think this may be specific to his bike on the washers and grommets and stuff.
I ended up mounting the fender like this. Someone PLEASE let me know if this is a bad idea. Seems to be fine though.
The fender mounts fill the gaps in the top mounts on the right side in my case. The bottom is filled with 3 washers
And here's what the left side looks like
On to the caliper... I would suggest that you rebuild them before you put them on the bike; nothing is worse than getting something finished and having to pull it apart again. The caliper mounts the same as the normal factory caliper - just reversed - so nothing hard there. The steel brake line runs the same, though you may have to zip tie it to the guard, because there is no line holder on this side (fig. 3).
Check on the rebuild of the calipers.
So a little caveat on the bleeders. Since the calipers are not mirrored one side will have the bleeder on the top and the other will have it on the bottom. The holes for feed and bleed are NOT the same. I found out when one of the pipes would not come tight. Take a peek inside the holes and you'll see the bleeder is a nice big opening that the cone of the bleeder fits into.
My brake lines are just hanging out there for god and everyone to see. I may come back and get some custom lines made up and then just run them 2up out of the MC. But for now...
So I think I'd hose most of the FAQ, knock the caliper and hanger together, see what the gaps are, shim or shave depending on what you see (possibly with the fender mounts) and get on with having some fun. Maybe that's exactly what he's saying in the FAQ and I just over-thought it.
Really, I hope this helps someone, schmuck to schmuck.
Anyone feel free to correct me here as I have to get a working master cyclinder before I'll know for sure but I'll update this when I do.
