Standard Front Brake Upgrade

[natemoen]

I will hold you to that Cy, if I don't neat ya to it

[mro]

Question?

If you can lock up the front tire with stock calipers
how can changing them decrease stopping distance?

[crazy steve]

If you guys will wait a few days until I get over the crud I came down with last night (I'm hanging out in the house until I feel better...), I'll post a drawing of the bracket. It's actually super-simple to lay out.

And I'll throw out one more method for cutting the aluminum... If you have a table saw with a fine-tooth carbide blade (40T or more), these will cut thicker aluminum as long as you feed it in slow. Makes nasty chips (wear eye protection) and isn't all that good for the blade, but will cut it much faster than with other methods. Doesn't leave a smooth edge either unless the blade is new, so you'll have some hand work. This is how I cut out my 'hunks' of metal prior to machining them...

[natemoen]

Yeah I have cut quite a bit is metal that way. Usyally a fine cut wood blade flipped so it rotates backwards. Never cut anything that thick though!

[cywelchjr]

That's cool. I thought you had not mocked up a bracket for the stock forks, but if you have that will make life FAR easier.

[ManagerMike]

This sounds more and more doable. As soon as I get my paws on a set of these HD squeezers (have a cousin that works at an HD dealer),
I'll do the mod and post pics.
Just a quick thought on this however.... instead of modifying the rotors or the calipers to allow for the thickness difference, I'm thinking of "wearing" the .070" off of the pads with the side of an abrasive cut-off wheel or belt sander. We are only talking little better than 1/16 of an inch here, 1/32" each pad.
Then if it turns out that for some reason I don't like the results I can bolt the old calipers right back on, and if I DO like the results I can do the permanent mod next off season, or just "wear" the next set of pads 25 or 30 thousand miles later. What thinkest yee?

[natemoen]

That did cross my mind.

[crazy steve]

What I can tell you is when I did the preliminary fit-up on these, the calipers would just barely fit over the XS rotors. Now, the pads I have aren't new (but are very close), so with a set of 'well used' pads, yeah, you could make it fit. But I didn't want to have to deal with 'special' parts once I was done with this; trying to cut a set of pads down each time you need brakes isn't my idea of fun.

Plus, I like the idea of cutting the rotors because of the weight reduction; those suckers are heavy...

[crazy steve]

Bracket Template

Ok, as promised here's the template. Now, don't just print this and use it; by the time these are uploaded, downloaded, and subject to the vagarities of different printers, accuracy will suffer... This will get you close, but you still need to doublecheck the distances between the bolt holes as these need to be right. Here's the pic:

[IMG][/IMG]

That 'benchmark' is to give you something to scale when printing. To lay this out, start by putting a straight line in at least 7/16" from one edge of your material. Make a mark (again, at least 7/16" from the end) and that's the first hole. Go 4.405" from that hole on the line and make another mark. These are the holes for the XS forks. Now, using a compass and one hole for your 'center', swing an arc from the other hole. Measure 7/8" over on the arc and make a mark. That's the center of the top hole for the HD caliper. Draw a straight line from this mark through the 'center' mark. Measure 2.720" from the top HD hole and that's the lower hole. I swung 7/8" diameter circles around each hole as that's roughly the diameter of the stock fork tabs. All four bolt holes can be drilled with a 13/32" drill bit; that's a few thousandth under the stock size but should work if you have the hole centers right.

The 'cutaway' between the HD mounts is for caliper clearance; the shaded area is how the stock HD forks are, but all you really need is the lesser amount.

If you have a dial caliper, use that as a 'compass' to mark your holes. Scribe your line on the aluminum, centerpunch the first hole, dial the caliper to length and 'lock' it, then use the sharp 'inside' ears on the caliper to mark the next hole by pivoting from the first mark. Works pretty good....

Hardware/bracket material. The stock caliper ears (on both bikes) are .650" thick. I wouldn't go thinner than 3/8" material, and 1/2" would be better to avoid any flex, but that's your call. If you use the thicker material, you can use OEM HD mounting bolts, parts # 44160-00 and 44163-00 (two each), about $2 each new. These will match the caliper bridge bolts. Otherwise, you'll need four 10mm/1.5 bolts; two at 2.82" + and two at .88"+ (the + represents the bracket thickness). You'll also need four 10mm bolts/nuts to attach the brackets to the forks; the OEM caliper bolts will be too short. You'll also need four 10mm washers .075" thick to put between the brackets and the XS forks to properly center the calipers over the rotors. You'll need two 3/8-24 banjo bolts too. If you don't get these with the calipers, check around before buying new OEM parts; chrome ones may be cheaper . You might also check the local indy Harley shops; they have good used parts for cheap sometimes and might be able to fix you up with the hardware...

That's it!

[natemoen]

Plus, I like the idea of cutting the rotors because of the weight reduction; those suckers are heavy...

How much weight do you really think that 1/16" would save? The rotor I weighed only weighed 6.12 pounds (i know thats 18 + pounds between the 3), I doubt you will lose more than a pound, maybe 2 max.

[crazy steve]

How much weight do you really think that 1/16" would save? The rotor I weighed only weighed 6.12 pounds (i know thats 18 + pounds between the 3), I doubt you will lose more than a pound, maybe 2 max.

No, it's not going to be a big weight savings, but every little bit helps. This is unsprung weight too, so it should be a bit more noticable. You're reducing the rotor thickness at the friction surface by 25%, and that surface is roughly 65% of the total rotor area. So .65 X 6.12 = 3.978, then X .75 = 2.98. That would give you roughly a 1 lb weight savings, or about 16%. That's without drilling the rotor, so it's nothing to sneeze at. Better gain than what you'd get from drilling; if you went with a 60-hole pattern and used 3/8" holes, you'd only see about a .43 lb loss. Do both, and you'd have about a 1.3 lb loss for about a 21% reduction. Not huge, but short of going to a high-$$ aftermarket rotor, not bad...

[cowboybob998]

R1 calipers

I think Geezer was working on an adapter plate to put R1 (I believe) calipers on standard forks, and I believe that no other mods were needed to make them work other than the adapter. I think you need a different MC with the R1 calipers thought.

You are better off going with the harley calipers, i say this because i converted the calipers on my 86 venture to the R1, the first set of calipers i got off of ebay were shot and needed to be rebuilt, to much money was cheeper just to buy another set off of ebay, it will cost you an arm and leg to rebuild the r1 calipers, about 200 bucks, i think from what steve said the harleys are cheper to rebuild.

[TopCatGr58]

Hey Steve,

Resurrecting this thread, I finally broke down and tore down my front brake calipers only to find the unobtainium special caliper pistons pitted severely, and instead of trying to get new pistons, decided I would look into doing this mod...but for a Special.

However, the prices for the H-D calipers have gone up quite a bit, and many of the ones that are only 1 caliper all seem to be for just 1 side??

You mentioned NOT to get ones for the V-rod....why? Too thick or deep so that there's not enough clearance between spokes and rotor???

I remember seeing a post/link re. a place that was making custom made special pistons....will check the LINKS section, as well as a search for it. Depending on what I find, I may have to get the replacement pistons?

T.C.

[fredintoon]

Controllability

If you can lock up the front tire with stock calipers
how can changing them decrease stopping distance?

Hi Mike,
it's that you can stop with a two-finger lever pressure rather than with a strangler's death grip.

[crazy steve]

Hey Steve,

Resurrecting this thread, I finally broke down and tore down my front brake calipers only to find the unobtainium special caliper pistons pitted severely, and instead of trying to get new pistons, decided I would look into doing this mod...but for a Special.

However, the prices for the H-D calipers have gone up quite a bit, and many of the ones that are only 1 caliper all seem to be for just 1 side??

You mentioned NOT to get ones for the V-rod....why? Too thick or deep so that there's not enough clearance between spokes and rotor???

I remember seeing a post/link re. a place that was making custom made special pistons....will check the LINKS section, as well as a search for it. Depending on what I find, I may have to get the replacement pistons?

T.C.

Here's the link to the stainless steel replacement pistons....

http://hvccycle.com/brake-caliper-pistons.html

As to the Harley calipers, you're looking for this style:

http://www.ebay.com/itm/2004-Harley-Davidson-FL-Touring-FLHT-Front-Brake-Calipers-HD-/170802545784?pt=Motorcycles_Parts_Accessories&hash=item27c4a00478&vxp=mtr

...which was found on almost everything they built from 2000-up, including the V-rod (which I wasn't sure of when I first posted this). You'll find these in both black and silver finishes, chrome if you want to spring for it. Exceptions that don't work are the '04-up Sportster and anything pre-2000. The later big Harleys and some V-rods got Brembo calipers (larger yet pads) starting in '08 on some models and everything I can find says these will interchange with the earlier units, but they're going for a lot more money. Yes, prices have gone up some on the earlier style too, but you'll see prices all over the map; it pays to shop. Main thing to look for besides price is to make sure the caliper is complete; I see quite a few sets that are missing the pad retaining bolts as some guys are buying some cheaper aftermarket chrome replacements that don't come with them so they rob them off their old ones. Those are about $20 each to buy....

The reason you see a lot of single calipers is Harley doesn't put dual discs on everything; only the big touring bikes get them as standard, their other models have them as optional. And a lot of sellers sell them each rather than sets, so again, you need to shop.

You're still going to have the problem of fabbing a mount to the fork lowers on those special forks. To be honest, unless you remachine the existing mounts, I don't see a way to get a sturdy mount with only a one-bolt attachment.... no matter what brand of caliper you use.