Monday, December 8, 2008

New Engine Break In and AFR

On many occasions over the past couple years I've heard the term "break in map". I've never really understood what this meant so I decided to ask around. I was really surprised at the answers I got...the most common was "I like to run it richer during break in so the engine won't overheat". This, under no terms, is the correct way to break in an engine.

As I've said before on this blog, I'm not here to debate how to do engine break in. There are dozens of opinions but I will say confidently, running it rich in the beginning is not the way to do it. Doing so will permanently damage the engine causing power loss you will never get back. The idea is to run the engine as little as possible to get close to a proper desired a/f ratio so nothing is damaged, then run it hard during the break in once you acheive that desired ratio. Outling break in procedure is important to explain why rich mixtures during break in is a critical mistake. Here's why...

The piston ring seal is really what the break in process is all about. Contrary to popular belief, piston rings don't seal the combustion pressure by spring tension. Ring tension is necessary only to "scrape" the oil to prevent it from entering the combustion chamber. If you think about it, the ring exerts maybe 5-10 lbs of spring tension against the cylinder wall. How can such a small amount of spring tension seal against thousands of PSI (Pounds Per Square Inch) of combustion pressure ?? It can't.

So how Do Rings Seal Against Tremendous Combustion Pressure ??
Rings seal against the combustion pressure from the actual gas pressure itself. It passes over the top of the ring, and gets behind it to force it outward against the cylinder wall...which is why they are beveled. The problem is that new rings are far from perfect and they must be worn in in order to completely seal all the way around the bore. If the gas pressure is strong enough during the engine's first miles of operation (as in WOT), then the entire ring will wear into the cylinder surface, to seal the combustion pressure as well as possible.

The Problem With "Easy Break In" ...
The honed crosshatch pattern in the cylinder bore acts like a file to allow the rings to wear. The rings quickly wear down the "peaks" of this roughness, regardless of how hard the engine is run. There's a very small window of opportunity to get the rings to seal really well ... the first 20 miles. If the rings aren't forced against the walls soon enough, they'll use up the roughness before they fully seat. Once that happens there is no solution other than bore, new rings/pistons, and start over.

What compounds the problem is the overly rich fuel mixture I mentioned above. The rich fuel mix will dilute the oil. Dilute the oil too much and you'll wash the oil from the cylinder walls because the rings aren't seated and fit tightly to prevent the mix from staying above the top ring. Remember the rings aren't sealed in the beginning, so the raw fuel washes down the cylinder and piston skirt. When you do that, you accelerate the wear on the ring and cylinder wall before the ring has time to seal...then you don't build the cylinder pressures you should and the engine will NEVER reach its full power potential....EVER.

This will probably be my last blog post for 2008. I would like to wish everyone the best during the holidays and a happy new year. See ya in 2009!

Happy Motoring!

Saturday, November 29, 2008

Engine Oil

Since we covered filters, and I haven't posted anything in a while, I thought it a good time to cover some facts about engine oils. I know there are many opinions but again, what I'll state here is fact and you can make your own decision based off it. I also won't get into the synthetic vs petro based decide.

The most common questions I get asked is "can i run regular car oil", "why do i have to buy harley oil", and "can i run diesel oil like Rotella"? So here we go....

To first take it all in, we need to know what the API ratings on oil mean. So what do the API ratings mean? For starts, the "C" specification is for diesel (compression ignition) and the "S" series is for gasoline (spark ignition). Within each category is a series of specifications like CC, CD, CE, CF, CG, CH, SG, SH, SJ, etc. Look at the API website for better info. If you just want the short it is.

The primary difference between normal auto oil and HD oil, Syn3, Amsoil, Rotella, and many other synthetics is the "CF" standard. It is defined as "CF - Indirect-Injected Diesel Engine Service - Service typical of indirect-injection diesel engines and other diesel engines that use a broad range of fuel types, including those using fuel with high sulfur content; for example, over 0.5% wt. Effective control of piston deposits, wear and copper or brass-containing bearing corrosion is essential for these engines, which may be naturally aspirated, turbocharged or supercharged. Oils designated for this service have been in existence since 1994 and may be used when API Service Category CD is recommended. Also recommend where severe axial loads may be present."

Rotella and other diesel oil:
Diesel engines run much higher compression ratios than gas engines and they run a lot hotter, so the oil is formulated to deal with this. At first we would think this to be an ideal scenario for our performance engines...but they produce a lot more dirt in terms of combustion by-products. Diesel-rated oils typically have more detergents in them to deal with this. This is where the problem comes's not unheard of for diesel oils to clean a gas engine so well that it loses compression. Diesel-rated oils also have an anti-foaming agent in them which is unique to diesel engines, and not needed in gas engines. So what are the advantages?....the CF rating (read above).

Regular automotive oil:
Most do not have the CF rating and also lack the heavy detergents and anti foaming agents. Good but I want the additional lubrication and protection CF provides.

To make it as easy as possible...I'd want the "CF" protection that diesel oil provides but without the harsh detergents and anti-foaming agents. This rules out regular automotive oils and true diesel oils. It leaves us with HD oil and synthetics like Amsoil and a couple others...both of which have the CF ratings.

Sunday, September 14, 2008

Dyno Variables

The values posted on Head Quarters builds for Horsepower, Torque, and MPG are easily attainable with a good tune. They are VERY conservative and do not reflect the maximum values we regularly see with our complete kits, a GREAT tune with no detonation, as well as proper exhaust and carb/TB selection. If you are not getting the numbers as stated or higher, there is either an issue with the tune or the assembly.

We state a range for reasons I will outline below. None of these points are intended to be comparative or derogatory and come from our expericences as well as feedback from qualified dyno tuners across the US, Canada, and Europe that we deal with regularly:
  • Variances in dyno brands, models, and software versions which can account for as much as 10%
    • Superflos average 10% lower than Dynojets
    • Newer Dynojets or those with recent software updates on average report lower numbers than older units
    • Proper dyno maintenance
  • New developments in the Harley product line
    • Industry wide, many tuners report that late models produce 5-7% lower numbers on average than previous models with the exact same build specifications. Logical theories have suggested
      • Parasitic loss in the transmission due to gearing changes and helical cut gears
      • Parasitic loss due to the ratchet style primary chain tensioner locking too much pressure onto the primary chain
      • Throttle by wire and the throttle plates tendancy to not open to 100% throttle until 3000rpm on average
  • Tuning method and data reported
    • Gear selection for the pull
    • Correction and smoothing factor
    • Air/fuel and Ignition timing chosen
    • Tuning device (PC, SERT, DTT, etc)
    • Ventilation system in dyno room
  • Mechanical
    • Proper tire pressure
    • Correct throttle cable adjustment
    • Clutch slippage
    • Tire traction on drum
  • Atmospheric Conditions
    • Dyno correction factors are designed to compensate for these issues, however results can still be affected by altitude, temperature, humidity and barometric pressure

We go through great lengths to ensure the quality of every product we produce. We are not a factory and don't have a huge assembly line or labor force putting parts together. Everything is re-engineered by the same human hands, every time, to exact standards to ensure consistancy...just the way it's been for over 30 years. We have control over this...but not the other factors above.

A dyno is a tool not a defacto standard. There is no such thing. Look at the performance before and after the build...just make sure everything above is EXACTLY the same.

Monday, August 25, 2008

The Ol' mans build

Last weekend I had the chance to do something I've never done before... My mom and dad split just after I was born and my dad and I really didn't get to know each other that well until I hit my early 20s. Regardless, he and I both had a passion for motorcycles and that's pretty much what brought us back together. Guess what they say is's in the blood. Anyway, he (and my father-in-law) went on the Head Quarters PowerTour with us and we all had a blast. Only problem was that he was on a stock scoot...2008 FLHTCUI...and had a hard time with falling back when we starting hitting the mountains. Needless to say, he wanted to keep that from happening again. So we built our first engine HQ 103ST. He pulled in on Friday eve, had er running by Saturday afternoon then got rained out. After some tuning on Sunday, he rolled home with an "ok for now" tune at 102hp and 122ftlbs with stock head pipes and Vance & Hines Classic Slipons. There's more in there but the head pipes I think are holding the HP back a bit...will keep you updated on that.
Had to throw a couple pics in of em...well, you can tell it was a bit late. I don't think the man has ever seen a clock tick past midnight. We had a great time though...the look on his face was priceless after that first WOT run. He forgot to put his backrest back on and according to him..."that build made that seat REAL SLIPPERY"!! So, grab some beers, pull the grille down to the garage, invite some friends/family over, and support your local HQ Build Party! That's it for now....Happy Motoring!


Thursday, August 14, 2008

Octane and Ethanol

This question has become ever more popular...I probably get it several times a week and it involves octane, ethanol, and how states require fuel to be mixed. Before I get too involved, let me first explain what "octane" really is. The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, you get detonation. Lower-octane gas (like 87-octane gasoline) can handle the least amount of compression before igniting where higher octane like 93, can handle more compression, which is why we run it in high performance engines. Keep in mind the effective compression limit for 93 octane is very close to 10.5:1 CR (at sea level). To make it as simple as possible, the higher the octane, the "less flammable" the fuel.

So here's the scoop:

We already know we have E-85 fuels now which is a mix of 85% ethanol and 15% gasoline but let's consider the much older alternative which is E-10...10% ethanol and 90% gasoline.

Ethanol is currently blended into about 70% of US gasoline, the majority as the E10 blend. Each state determines whether gasoline needs to be labeled if containing ethanol, so if you're in an area where labeling is voluntary or not required, you wont always know if the gasoline contains ethanol. Ethanol blends are offered extensively throughout the Midwest and are becoming more and more widely available from coast to coast. Because pure ethanol has an octane rating of 113, adding 10% ethanol to gasoline raises the finished fuel's octane rating by 2 or 3 points, improving the fuel's performance. Unfortunately, if you live in a state that doesn't require labeling, you don't know if you are getting a TRUE 93 after ethanol, or 93 plus 2-3 giving you 95-96 octane.

The problem is that if your bike is tuned on 93 octane (no ethanol) and all of a sudden you use E-10, you may feel as if you've lost power. You have, but not's not because it's "bad gas", it's because the fuel is less flammable. This can be worked out with proper ignition timing adjustments. Call your local clean air force, energy association, etc and ask if your state is one that requires ethanol blending to be posted at the pump. If they do and it's posted as 93, rock on. If they dont and they tell you the posted octane is before E-10 is added, you can be more aggressive with igntion timing and pick up more performance than those with a true don't sweat it....give it what it wants. I feel it important to note this is why "universal fit all" timing tables don't always work and can be another factor as to why identical builds can produce mildly different dyno results. A 2-3 octane jump can be worth a few degrees of timing.

Side note: altitude plays into this as well but we've already talked about that on the I won't go there. Camshaft selection also has a HUGE MONSTER affect on this too...that's why Head Quarters is here to help you out ;)

E20, E30, or E40 is already under development and testing so be ready for it.

Happy Motoring!
Kevin Baxter

Saturday, August 2, 2008

Cyl Head Temps and Lower Fairings

I installed lower fairings on my FLH over the winter and have been riding with them on up until yesterday. It's bouncing close to 100F here in Atlanta, so needless to say, it's been a little warm. Over the past few weeks I've been doing some tuning, building maps, etc and of course I like to always keep track of cylinder head temperatures. I found what I expected on the front, just below 300 deg at the spark plug...perfect. Then I checked the rear...375F! Yikes...that's a bit too hot for my taste. I of course played with fuel mixtures and timing and nothing seemed to make a sizeable difference until I took the lowers off (with are "vented"). I was expecting it to lower temps a little but not 70F lower! Just an FYI.... Happy Motoring!


Friday, August 1, 2008

Oil Filter Research

I decided to do some oil filter research after what we found while designing the Black Ops lifters. Considering a lifter does such a great job of trapping small particulate, I figured we should be running the best oil filters we could get our hands on.

Abrasive engine wear can be substantially reduced with an increase in filter single pass efficiency. Compared to a 40 micron filter, engine wear can be reduced by 50 percent with 30 micron filtration. Likewise, wear can be reduced by 70 percent with 15 micron filtration. That being said....

The following is a good rule of thumb. A filter is considered nominally efficient at a certain micron level if it can remove 50 percent of particles that size. In other words, a filter that will consistently remove 50% of particles 20 microns or larger is nominally efficient at 20 microns. A filter is considered to achieve absolute filtration efficiency at a certain micron level if it can remove 98.7% of particles that size. So, if a filter can remove 98.7% of particles 20 microns or larger, it achieves absolute efficiency at that micron level.

Most off-the-shelf filters are based upon a cellulose fiber filtration media. Most of these filters are, at best, nominally efficient at 15 to 20 microns. They won't generally achieve absolute efficiency until particle sizes reach 30 microns or higher. High efficiency oil filters have filtration media made of a combination of at least two of the following: glass, synthetic fibers and cellulose fibers. Those that use all three are generally the best in terms of filtration. Those that use only two will fall somewhere in between. The best of these high efficiency filters will achieve absolute efficiency down to about 10 microns and will be nominally efficient down to 5 microns or so.

I researched many different filter brands (of course some were private labels which crossed over) readily available for HDs and would you believe that the Harley Super Premium 5 brand was the only one I could find rated at a nominally efficient 5 microns?

Happy Motoring,

More Lifter Info

One of our HQ Techline members, Battersby, was kind enough to provide these pics while "pre-charging" his lifters. Thanks. Here's a few more facts about lifters from Doug:
There is an expression in the lifter industry. ‘Hydraulic lifters are the best oil filters on the market’. In simple terms, that means dirt can get in a lifter through the oil feed, but can’t get back out. A lifter will capture dirt particles as small as 1 micron. A top quality fine oil filter only captures dirt 5 microns or larger. So clean engine assembly is a must.Over 90% of failed lifters are a result of dirty oil. Wear as fine as 50 millionths of an inch (that is 1/2 of 1/10th of ONE thousanth of an inch can make a lifter fail. And it takes only seconds.Clean engine assembly, clean oil and priming of the lifters before initial start up is essential.
Happy Motoring!

Tuesday, July 29, 2008

Octane Boosters

I occasionally get asked about the use of octane boosters in performance engines. While in some rare cases they are necessary, they are NOT in our builds if tuned properly...primarily because we make sure to put you into a build that fits your riding style and conditions. This issue came to me today from one of our dealers...their dyno tuner in fact, who is very capable, was kind enough to send me these pictures. As you can see, there is an extensive layer of iron and manganese deposits on the plug insulation and electrode as well as the oxygen sensor for the closed loop fuel system thus corrupting the vital control of the air to fuel ratio. This generally results in a rich bias, compromising both emissions and fuel economy.

The primary ingredient used in most octane boosters is a chemical called methyl cyclopenta dienyl manganese tricarbonyl, or MMT. In VERY controlled and minute quantities (.018 grams per liter...or a couple drops per gallon) it's not harmful however, even the slightest over mix can cause what you see here as well as increased valve and combustion chamber deposits.

General Motors (GM), and others have reported spark plug fouling with MMT. Reports indicate that spark plug failures are due to iron and manganese deposits on the plug insulation and electrode, resulting in:
• Increased hydrocarbon emissions from the incomplete combustion of fuel
• Premature component failure (e.g. plug and O2 sensor) at circa 10,000 km, where
normal life would be more than 100 000 km.

Despite what the packaging says on various octane boosters about being "safe for oxygen sensors", if they contain MMT or Ferrocene, I would highly recommend against using them....of course as better advice, I wouldn't recommend using any at all. Happy Motoring!

Kevin Baxter

Friday, July 25, 2008

How To Check Crank Runout

This is especially important when installing gear drive cams. Check runout on the pinion shaft (opposite side of crank as shown). If you find a total runout of .004" or more, we advise you not to run gear drive. Happy Motoring!!

Kevin Baxter

Thursday, July 24, 2008

New Lifter Install

Many say the best thing to do is to let your lifters soak in oil overnight before installing...if they are very good lifters, oil will not magically find its way into the lifter body. It's always a good idea to "preload" your lifters before running them. You are dealing with tolerances of .00001" when messing with's a tip:
  1. Cut off a 4" piece of 5/8 rubber heater hose and slide it over the top of the lifter but leave the small hole on the side exposed.
  2. Submerge the lifter into oil that you will be running in the engine and make sure the small side hole is in the oil.
  3. Use your hand to join the other end of the hose to a shop vac.
  4. Run the shop vac so that the oil will be sucked into the lifter.
  5. Check every 30 seconds or so...when you see oil puddling on the lifter plunger inside the hose, you know it's full and ready to be installed.
  6. REMEMBER!!! This will extend the time it takes for the lifters to bleed down for pushrod adjustment...MAKE SURE EACH VALVE IS SEATED before you rotate the engine or move to the next pushrod.

Happy Motoring!

Ahhhhh....a new blog.

This would be the first official post to the Head Quarters blog. Of course we already have the HQ techline where Doug and I can answer your questions....this is a bit different. Here's where I'll post everything from brief tech articles, tips and tricks, an occasional video or pic, or just updates with what's happening at Head Quarters.

Thanks for stopping by...