My rear brake is like new again! Here's how I did it.

As my previous post says, I rebuilt the rear master cylinder a few weeks ago. The rebuild went fine, but the pedal feel was still soft and the pedal travel was long. The brake felt strong enough to be serviceable, but definitely not fully there. On advice of a fellow Sportster owner I tried the following. I gently pushed the caliper piston all the way back by using a large screw driver between the pad and the rotor. It is not hard to do if the caliper is in good shape. Does not take much force. I then jammed the pad with the screw driver so that the piston would stay pushed in when I apply brake pressure. I then proceeded to bleed the brake the old fashioned way:

1. Open the bleeder
2. Gently push the brake pedal
3. Close the bleeder
4. Release the brake pedal

I repeated the above steps three times, then added some brake fluid to the reservoir and pumped the pedal with the bleeder closed a few times. The pedal travel became mush shorter and the feel became much firmer. I then removed the screw driver from between the brake pad and the rotor and gently pumped the pedal until the piston came out to meet the rotor. The pedal feel and travel remained good. Went for a ride and was amazed at how much better the brake felt. I would say it's 100% back to normal now.

Rebuilding the Rear Master Cylinder

I have received the rebuild kit for the rear master cylinder (HD P/N 42810-04B) a few days ago. The kit contained the following items:

• new primary seal (cup)
• new piston
• new piston (secondary) seal
• new piston return spring
• new C-clip for the pushrod retaining washer
• new pushrod rubber boot
• new spring pin
• a pouch of grease
• a pouch of brake assembly oil
• a set of instructions on how to use the kit

Upon examination of old vs. new parts I immediately saw a defect in the old piston return spring that would explain the primary cup failure. If you look at the pictures, the new spring is on the left and the old is on the right. The new spring has a very flat surface at the top end. This is the end that is in direct contact with the primary cup. The little nub on the cup fits into the hole in the spring and the piston pushes the whole thing from the other side of the cup inside the bore. Look at the old spring's mating surface. It has high points that will create uneven pressure on the rubber cup and eventually wear cracks in the rubber, which is exactly the mode of failure here.

I am not sure if something happened to the spring to create this uneven surface or it was like that from the factory, but I can definitely see how this will cause problems with longevity of these cups. Every rear MC failure (talking rubber-mount here) I have seen out int he Sportster community had this cup tearing in a very similar way. It may be that excessive pumping during the initial bleed of the system compresses the spring to the solid state (coils binding) and then the pressure from the piston collapses the thin sheet metal of the flat mating surface around the spring wire underneath. I am just guessing here. The only way to know is to take my MC apart in a few thousand miles and see what the insides look like. I may do this in the future, but for now I am just trying to get my bike back on the road.

Rear Master Cylinder Failed!

Well, it happened. The rear master cylinder on  my Sportster failed at 41,600 miles. It really wasn't all right since the rear pad change at 30,000 miles. The rear brake has been weak and required a bit pf pumping once a day to get the pedal to not sink too far down. Once pumped up it would stay up for a relatively long time (days). The rear brake was not totally mushy, but it was not all that strong. I could still lock up the wheel, but with more effort than I thought was necessary. Anyway, since the brake was sort of serviceable, I left it alone until an opportune moment to deal with it. Well, that moment arrived a few days ago when I removed the rear wheel for a tire change. I get my tires online at Motorcycle Superstore which has the best prices on tires for my bike, BTW. I then remove the wheel assembly and take it to a good shop to mount the new tire. So, while the wheel was off the bike I decided to bleed the rear brake and get rid of that funkiness.I hooked up my MityVac and proceeded to vacuum bleed the brake via the bleeding screw on the caliper, which I removed from the swing arm and hung up such that the bleeder screw was the highest point in the system. This causes air bubbles to collect at the bleeder and not in that arch the brake line makes when the caliper is on the swing arm. If you own a rubber mounted Sportster you know what I mean. Anyway, after bleeding I had NO REAR BRAKE AT ALL! WTF?! Well, I read up on various forums, but mostly here that this is a rather common issue. After changing the pads and pushing the rear caliper cylinder back to accommodate the new pads many, many, MANY people observe the failure I had. Even the pictures look the same as what I found when I disassembled my rear master cylinder. I have ordered a rebuild kit and will rebuild this thing and see how things go.

Cold ride yesterday

I went for a ride yesterday and damn near froze my butt off! It was way colder than I expected. I cut the ride short and made myself a hot beverage when I got home. Brrrr! Where is that spring?

Great ride today

As I planned yesterday, I did go on a ride today. I started by giving the bike its Spring Bath (it usually gets very few baths, so this is special :) ). I then rode over to North Star where my older son Jonah does most of his home schooling. The staff there was interviewing parents of teens who go there for a video clip to put on their web site. I did my interview and just as I finished the interview my riding buddy Bill pulled up to the building (as per prior arrangement). We left Hadley around 1 pm and headed over the Rt. 9 bridge to Northampton and from there north towards Deerfield on Rt. 5 and 10. From Deerfield we took 116 north to Ashfield, which is the best piece of motorcycling road around here and is probably a mini Dragon. From Ashfield we took 112 north to Vermont border and in Vermont we took Rt. 100 north to Rt. 9 east, which is another amazing road with a great overlook of the valley to the south and east. Rt. 9 east leads straight to Brattleboro, which was our tentative coffee break stop. We had our respective beverages in a great little coffee shop (I had tea, Bill had coffee) and headed out of town on Rt. 5 over the Connecticut River to New Hampshire, where the same road becomes Rt. 119. We followed this rode along the river to Hinsdale, NH where it meets Rt. 63. We took Rt. 63 south (again along Connecticut River) all the way to Massachusetts. By the time I got home around 6 pm I had 140 miles on my trip odometer covering 3 New England states. That's one of my favorite loops around here. But not the only one.

Ricor Intiminators

I purchased and installed Ricor Intiminators for my front end. I have installed them according to instructions cutting about 0.5" off the preload spacer (the intiminators take about 0.5" just below the spring). I have added this upgrade in search of better handling and more stability from the bike in the twisties. Time and miles will tell how well these things work and if they are worth the money. I will update this post when I have more info. So far I can say that the install is very simple. Drain old oil from forks, take the springs out, pop the intiminators in, add a bit of oil, push the intiminators down to the bottom with a spring, but keep the spring out for the time being. Add correct amount of 5W Amsoil Shock Therapy (fork oil recommended by Ricor for this application), add spring and preload spacer (adjusted for the 0.5" of the intiminators), button it all up and it's a done deal.

Update April 16, 2010
So far I have logged over 300 miles with the intiminators in the front end and the short summary is: THEY ARE GREAT!!!

The longer story goes as follows. Right after installing the intiminators and going for a ride around the block you may say to yourself, what the heck is the big deal?! Why did I just spend close to $300? Well, that's just the thing. Around the block or on a gentle ride to your favorite watering hole you may not notice a significant difference. And frankly, in those situations Sportster is already good enough anyway. Well, some of the smaller road imperfections seem to go unnoticed even at an easy pace, but that's not worth $300, I don't think. So, if you are thinking of buying these things and expect your bike to become a Cadie on two wheels, forget it. Here is where the intiminators really kick in. Twisty back roads where you tend to go a bit over the speed limit :) The thing is that even on those roads the bike does not feel much different, except when you look at the speedo. First time I did that I had a bit of a shock and quickly closed the throttle instinctively. I was going around curves I knew very well at about double my usual speed without ever realizing it. Everything about the turn felt the same. The lean angle, the effort at the handlebars, etc. The speed, however was much higher. Catching a small pothole (or even a large one) in the curve did not upset the bike any more. The stability of this Sportster was improved by an order of magnitude. I am still playing with some settings like the height of fork tubes in the triples, etc. But in general the front end is very, very VERY good right now. It also made the rear end behave better. I have dialed the 1200S shocks in and now I have pretty sweet handling Sportster. I am very impressed and highly recommend the intiminators to anyone who is frustrated when pushing the Sportster through the curves (too slow, way too much lean, I am going to scrape stuff if I go any faster around this curve, that type of frustration).

1200S Showa Shocks

I've been running 13.5" Progressive Suspension 412 shocks on this bike for a long time. They ware a great improvement on the stock shocks. But they still felt harsh and the handling still left a lot to be desired. I knew of the 1200S fully adjustable shocks for a while and finally got my hands on a pair from eBay. These shocks came stock on the venerable Sportster 1200S Sport and are made by Showa. They have adjustable spring pre-load (4 settings), adjustable compression damping (15 settings) and adjustable rebound damping (10 settings). They measure about the same as my stock shocks, 13.25". They seem to have a much softer spring than the Progressive 412, but I don't know that for a fact.

I mounted them in reverse, left shock on the right and right shock on the left to accommodate my Easy Brackets with saddle bags. This way the oil reservoir is forward of the shock rather than behind it, which would interfere with the saddle bag brackets. The small problem with this is that the left shock can and sometimes does interfere with the rear brake caliper. This can be solved by adding about 0.5" more spacer to get the shock away from the caliper.