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  • Coach Robb

    10 Body Indicators That Tell You When to Workout & When to Back Off!

    By Coach Robb

    TIME TO REST - Pay attention to these 10 body indicators to gauge when to work out and when to back off!   If you don’t take time to rest and recovery, your body wont adapt to the stress of training and racing – and as a result you won’t get stronger or faster. If you neglect recovery for too long, you will start to lose strength and speed.   Here are some symptoms to look for: First your sleep patterns will be off (tired and you can’t sleep, restless sleep, etc.). Second your energy levels will be negatively affected. Third, you will begin to get sick more frequently (and take longer to heal from the virus). Fourth, your appetite will become suppressed.

    Remember, over training is not applicable only to elite athletes and professionals, recreational athletes have to balance, personal, professional, bills, children, inadequate sleep, etc. which is what makes recovering from your workouts and racing even more difficult.  
    Symptom Evaluation
    See if you are experiencing any of the following symptoms:   Symptom #1-Body Mass
    A 2% drop in weight from day to day indicates a body-fluid fluctuation. More than likely, you didn’t hydrate enough to offset heat, humidity, intensity and duration. Dehydration negatively impacts both physical and mental performance and could compromise the quality of your next workout or race.   Symptom 2-Elevated Resting Heart
    An elevated resting heart rate is a significant indicator of stress within the body. An elevated HR indicates that your nervous system is in that “fight or flight” mode which results in elevated hormone levels to provide more oxygen to the muscles and brain. Your body doesn’t know the difference between and physical and psychological stress. A hard day at work and/or a hard workout or race both require additional recovery protocols.   Symptom 3-Sleep Quality: you wake up and don’t feel fresh.
    Quality sleep: falling asleep quickly, deeply and staying there for a long period of time will allow your body to release the much needed growth hormone (hGH) necessary for rebuilding muscle and burning body fat. Several low quality nights of sleep will decrease your reaction time, immune system, can cognitive functions – not a good scenario when it comes to quality workout or high end performance on race day.   Symptom 4-Hydration: your urine is dark yellow
    Unless you are taking B vitamins, a dark colored urine can be an indicator of dehydration. Your urine is an easy indicator of your water levels throughout your body.   Symptom5-Energy Levels are Low
    Honesty is the key here. You know the difference between being tired and having low energy. Being tired is about recovering from yesterday’s workload. Being low on energy is a at a completely different level. Athletes think they can block out signs of fatigue and push to the next level of fitness, performance just doesn’t develop in this environment.   Symptom 6-Mood State: your moody (and even cranky).
    When your body is overwhelmed by stress (training, racing, work, family, etc.), it produces the stress hormone cortisol that can cause irritability and/or anxiety. Stress also halts chemicals like dopamine, a neurotransmitter in the brain that has a big bummer effect on mood when depleted. Crankiness means not enough recovery.   Symptom7-Sick Frequently
    Any illness or even a woman’s menstrual cycle, will increase your need for energy to refuel your immune system, which is having to work overtime. This translates into fewer resources available for recovery from training.   Symptom 8-Pain: your excessively sore or have a nabbing injury.
    Whether you are sore from over worked muscles or have an injury that continues to linger is an indicator that your body needs more energy to put towards the repair, which extends your total recovery time.   Symptom 9-Performance is sub-par.
    This is a subjective measure of workout quality, not quantity nor intensity. If you perform well on a particular workout, you would rate that workout as “good”. If you have a sub-par performance or feel like you are struggling to complete that same workout, you would rate that workout as “poor”. Trending workout quality – multiple poor workouts in a row – is one of the easiest ways to identify the need for more recovery.   Symptom 10-Oxygen Saturation: low oxygen levels.
    The amount of oxygen in the hemoglobin of the red blood cells can be measured and is thought to be an accurate assessment of recovery because of the association of high oxygen saturation levels and higher energy levels.   Evaluation Time: count how many of the above symptoms you have experienced over the last week and then compare this against the following:
    0-1: Green Light: you are recovering adequately and can maintain your normal volume and intensity
    2-4: Caution: You can complete your hard workouts; however, cut the workout short if you are struggling to complete the first couple of intervals after a long warm up
    5-6: Warning: This is the zone where you are close to tipping the scales and becoming over-worked, sick and injury prone. You need to add a second rest day to your week
    7-10: Danger: You are IN the danger zone and need to take one week completely off (no sport specific training); increase your high quality food intake and take 2 hour naps each day.   If you want me an my staff to review if you should take a break from training and racing, please feel free to contact us at Contact@CoachRobb.com.
    • 2 comments
    • 3,638 views
  • Paul Olesen

    Help! - Bike Only Starts When Pushed

    By Paul Olesen

    Today I want to talk about a situation I hear all too often. Someone’s bike, whether it be a two-stroke or four-stroke, only starts when it is pushed.

    Before I discuss potential causes for this scenario, take a moment to think through the situation yourself. What mechanical factors would result in either a two-stroke or four-stroke only starting when it is bump started?

    In either case, the reason the engine is able to start when it is push started is because it is able to build more compression than it otherwise could when it is kicked or the electric starter is engaged. More compression is achievable because the cranking RPM is higher than what’s possible with the aforementioned starting methods. With a higher cranking RPM for a four-stroke, more air will fill the cylinder on the intake stroke, and for a two-stroke the scavenging process will be improved. With this being the case we must look at reasons why the engine is struggling to build compression in the first place.

    Starting problems specific to four-strokes:
    1. Valve seat recession - When a valve seat wears out and recedes, the valve moves up towards the camshaft. This leads to diminished valve clearances and if left to run its course, the valve and shim will bottom on the camshaft’s base circle. This can prevent the valve from seating and make the engine hard to start. 2. The valve is bent - A valve with a serious bow to it may get jammed up inside the guide and not return all the way back to its seat. Bent valves typically result from an over-revved engine where the valves contact the piston. Valves can also bend to a lesser extent if they were mated to valve seats that were not cut concentrically to the guides, or they were paired with worn seats.

    3. The valve stuck in the guide - This is usually due to the engine overheating. When the engine overheated the clearance between the valve and guide diminished which caused metal to transfer from one part to the other, ultimately ruining the surface finish on one or both parts. Once this happens the valve may be prone to sticking in the guide until the engine warms up. 4. The valves and seats do not seal well - Worn valves and valve seats can compromise the seal between them. Valve and seat wear is a natural part of running an engine but can also be accelerated by ingesting dirty air.

    Starting problems specific to two-strokes: 1. The reed valve is worn - Reed petals that don’t close all the way, are chipped, or bent will not allow sealing of the crankcase and efficient gas flow up from the crankcase into the cylinder.

    2. An engine seal or gasket has failed - A two-stroke engine requires a well sealed crankcase and cylinder in order for it to scavenge gases efficiently. A worn crank seal, leaky base gasket, or problematic power valve seal can all make starting more difficult. Two and four-stroke problems: 1. The piston rings are worn - Worn piston rings will allow compressed gases to escape past them. 2. The head gasket or o-rings are leaking - Usually a leaking cylinder head will be accompanied by white smoke if coolant is being pushed into the combustion chamber, by coolant being blown out the radiator, or both.

    I hope you found this rundown of potential problems useful for diagnosing bikes that like bump starting over a kick or the push of a button. Can you think of any other problems that would lead to lack of compression? If so, leave a comment and share them. If you liked this post and want more technical info, check out my book, The Four Stroke Dirt Bike Engine Building Handbook. In it you will find over 300 pages of technical knowledge to help you get off on the right foot when rebuilding!

    - Paul
      Amazon DIYMotoFix.com  
    • 17 comments
    • 1,587 views
  • scottiedawg

    Turning Stones vol 1

    By scottiedawg

    The official ride video...Make sure to watch in HD The day started by waking up in a lavish hotel room at the Aranwa Resort in Urubamba, Peru. I had a couple of hours to eat breakfast, gear up, and drive across the valley to another fine hotel to meet up with Imad.

    A month prior, I received an email inquiry about running a one day hard enduro tour. I was available for the dates, so I began discussing the options for the tour. What I found out was that Imad, who lives in Dubai, was vacationing with his wife. He had come up with a brilliant plan to offer a full day at the spa for his wife which in turn allowed him to take advantage of another type of "SPA." Brilliant!

    Normally, I begin the tours from our headquarters in Cusco, but in this case, I was able to accommodate by starting at Imad's hotel in Urubamba. This gave me an excuse to bring my entire family to the valley, put them up at a nice hotel complete with all the fixings, and combine it with a one day enduro ride that has kept a smile on my face for days. I hung out with my family when I was at the hotel, then snuck out for a ride with Imad, then returned to spend more time with the family. Perfect!


    A couple of happy fellas I arrived at the Tambo del Inca, one of the finest hotels in Urubamba. I unloaded the bikes, prepped the lunches, warmed everything up, then headed into the lobby to find Imad.
    There he was with his happy wife who was about to be pampered for an entire day at the spa. She couldn't have been more happy. Imad was stoked to be able to enjoy Peru on a dirt bike. A win-win in my book!

    His wife made sure that I was legitimate. She was a bit concerned about me bringing him back in one piece. She mentioned the fact that there are two young kids who have a special relationship with their dad. I also fit that scenario, so I piped in my story to appease his wife that it was indeed my plan to bring Imad back alive and in good condition.

    Within minutes, Imad and I found ourselves mounting up on the two Husqvarna TE 300's. The trail head, just a minute away from the hotel was screaming for us to come try her out.
    The trail started out with a daunting strip of tight rock walled single track that resembles a jungle tunnel. It wasn't raining at the time, but it was extremely wet from the rain the night before. Imad pounded out the section with a bit of wonder about whether or not the rest of the day would be similar. I think it scared him a bit. To his pleasant surprise, I explained that it's not all as difficult, but that we would face countless obstacles in the days ride...But not to worry, it would all be worth it.


    Just a little rocky section to play around on We continued to work our way up the canyon with a goal of reaching the lower lake. I figured it would be a worthy goal to reach the lake, have lunch, then work our way back down the valley.
    Along the way up, we encountered numerous switchbacks, rock gardens, open meadows, creeks, and many a wet alpaca poop pile. The ride was just what Imad had hoped for.
    As a guide, I never know how people will do with the altitude. It can be a butt-kicker for some, and for others, it hardly makes a difference. With Imad, he struggled with it at first, but somehow caught a second wind as we reached the bottom of the last big obstacle before the lake. It was a rocky staircase climb that typically wreaks havoc when its dry, but this time it was soaking wet. We had  our work cut out for us.

    Like two mules, we worked up a good lather climbing up each of the rock steps. I made sure to tell Imad that the view would be worth it. Within a few minutes, he had the opportunity to agree with me. The view was just what Imad needed. In fact, he was so stoked about the view that he told me he wanted to try to reach the upper lake. We had plenty of time, so why not?
    Taking a break! The stakes go up on the route between the lakes. The terrain we saw below the first lake was only a warm up. Imad confirmed that he was indeed ready to give it a shot. Atta boy!
    The coolest part of the section is a waterfall that cascades down the mountain as the trail goes right through it. Check out the video if you want to see what I mean! We worked our way through the water, up a number of tight rocky switchbacks, and finally through a stand of scary red-barked trees where one would expect to find a creepy murderer with an axe. The ride is so fun that you forget the altitude. Just past the forest was the final climb before the upper lake. Imad was feeling his oats at this point. We crested the top to discover a sight to behold; The upper lake.
    It's absolute beauty. It was a perfect place to eat our lunch, take a million pictures and get ready to ride around the side of the lake to an untouched area where a dirt bike has never been. That is always a special treat that I can do for my customers. There are hundreds of places like that which can be explored on my tours.


    The upper lake never disappoints...well worth the effort! A bit of food and drink, then we mounted up and began a fun trials type of terrain complete with granite rock slabs, bright green grass, tons of mud, and views that continued to blow us away. We played around for a good hour until it was time to begin our descent to the bottom of the valley.

    Although it is the same trail, it seems like a different valley and route altogether. The downhill is sketchy. It's fast and rhythmic, but there are so many places to find yourself on your face. We experienced a couple of crashes, but coming down provides such a thrill...in fact, it's that type of thrill that keeps me riding. Pure smiles all the way down.


    A little ride through a waterfall We made it back to the hotel with nothing left in our tanks. No gas, nor energy. Completely smoked, but so satisfied! Another typical ride in the Andes of Peru! Make sure to check out the ride video to see what I am talking about. I can't wait to share another one next time around. Stay tuned and make sure to follow the blog so you can see the next post when it comes out.

    Until the next one,

    Scott Check out more of our hard enduro videos on our Youtube channel at MotoMission Peru Dirtbike Adventures.  
    • 5 comments
    • 979 views
  • Paul Olesen

    DIY Piston Ring Compressor

    By Paul Olesen

      Today I want to share a quick tip with those of you who are working on your own engines but just can’t justify buying a set of piston ring compressors. It’s entirely possible to make a perfectly good ring compressor from materials you can get at the hardware store. All you need is some plumber’s pipe hanging tape and a hose clamp that is sized according to your cylinder bore.

    To construct a DIY ring compressor from plumber's pipe hanger tape you will need to determine the length of tape required. This is easily done using the following equation for calculating the circumference of a circle. Length of Tape Required = Piston Diameter x π (Pi) When the tape is wrapped around the piston tightly, the final length may need to be reduced slightly so that the ends don’t butt together. Once the tape has been cut to length, make sure whichever side of the tape will be contacting the rings is smooth and free of little plastic burrs that could catch the rings.

    Simply lube up the tape, tighten down the hose clamp, and you are in business.



    Do you have a tip that makes compressing rings easier or cheaper? If so, leave a comment below! - Paul

    If you enjoyed this tip and want access to more like it, check out my book, The Four Stroke Dirt Bike Engine Building Handbook. On the fence about the book? Check out what other riders are saying: Thumper Talk Review

    Available at: Amazon.com DIYMotoFix.com  
    • 10 comments
    • 943 views
  • Paul Olesen

    What Spare Parts Do You Bring To The Track or Trail?

    By Paul Olesen

    With warmer weather and the riding season around the corner for many of us, I wanted to cover a topic that can either make or break an event. Whether you’re competing in a racing series or traveling to the track or trail, let's talk about event preparedness. More specifically, what spare parts should you keep on hand? Plus, what methods do you use to keep your spares organized?

    Honestly, I struggled with organization until I started working on this post. I had no method to my madness. Every time an event came up I’d do the same thing; throw a bunch of stuff in a box or the back of my van and head to the event. The sad part is I now realize this was a weakness of mine for quite some time, but didn’t do anything about it! Maybe you can relate?

    I finally said enough is enough. I don’t throw my tools in a cardboard box when I go to a race, leaving what I bring to the fate of my memory. So why would I do that with the spare parts I bring?

    I started solving this problem by compiling a spreadsheet detailing what spare parts I keep on hand for ice racing and hare scrambles. I realize that each discipline will differ and may have niche parts that should be kept. The goal here is not to definitively define what spares one should keep on hand, but to have a conversation and provide a resource that can be used to help people get set up based on their own needs.

    Once I took inventory of everything I felt I wanted to bring to a race, I went to Menards and went hunting for the perfect organized storage bin/toolbox. Here’s what I ended up with:



    Naturally, once I returned with the toolbox, my list grew and I probably need to go back for a bigger one. I intend to store a copy of the spreadsheet in the tote so I can keep tabs on inventory and know exactly what I have available.

    Should I get another bike, this system is easily replicable and my plan is to get another organized toolbox that goes with it.

    This system is how I went from being an unorganized “throw it in the van at the last minute” rider to a more relaxed well prepared rider. I’d love to hear how you handle event readiness, what you bring, and how you keep track of it. My hope is that by sharing our strategies we’ll save someone the misfortune of having a bad day at the track or trail. Perhaps I'll even end up with more things I need to add to my list.

    -Paul

    If enjoyed this post be sure to follow my blog and sign up for my newsletter!
    DIY Moto Fix Newsletter      
    • 16 comments
    • 672 views

Our community blogs

  1. What’s up ThumperTalk readers! I’m back with an update from this past weekend at the Southeast Loretta Lynn’s Regional Championship at MillCreek MX as well as some thoughts going into Loretta’s prep.

     

    When I say that it was a long weekend, I mean that for more than just one reason! Between the drama of Open Pro Sport, 10 long and hard-fought motos, and some personal strifes, I was ready to leave the track with my tickets in hand. Of course, at the end of the day, I got what I went there to get… tickets to the ranch. With that being said, I will be going to Loretta’s in the 250A and College (18-24) classes.

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    Before I start, I just want to say how awesome it was to return to a high-profile race and be welcomed back by good people as well as fellow competitors. While Motocross is a highly competitive atmosphere, we all like to see each other in good health.

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    Loretta Lynn's SE Regional Championship at MillCreek MX, Photo my Martha @ MEPMX 

    While there was some foul play among the races in the Open Pro Sport class, in the form of riders jumping the gate, leaving us to run 4 full motos instead of 3; I certainly did not make things easy on myself in most my race scenarios. I was trying to reacquaint myself with the old scenario of a full gate with some of the top racers in the class. It is very different racing local A races compared to racing almost 40 guys who are gunning for the top 6 positions in order to guarantee their spot at one of the most prestigious motocross races in the world, and they will do almost anything to get there. It took a few motos to get myself together, all the while working my way through the pack and making some rookie (but costly) mistakes. As far as speed goes, the lap times don’t lie… the speed was there, despite racing a 250 against 450s on a track that eats horsepower and will allow you to go as fast as you want as long as you have the cajones to twist the throttle. That’s why it’s one of my most favorite tracks of all time! However, in this sport, if you aren’t winning, there’s always a story. I will note though, it’s been since November of 2015 that I’ve been on an MX gate drop like that. That reality hit me pretty hard sometime this past weekend. However, I am proud of myself for gaining tickets in the A class, only riding for 3 months after a year off, in one regional compared to others who run two and three regionals to gain their ticket.

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    Loretta Lynn's SE Regional Championship at MillCreek MX, Photo my Martha @ MEPMX 

    There were things I needed to learn about my riding, some things that I needed to have reinstalled in my mind about racing at the top level, and things that I need to focus on going forward. I believe “reinstalled” is an appropriate word because I knew going into the race what I needed to do, but there were things that I forgot, as far as the level of importance. Probably the biggest thing is the importance of the start. At the top level of amateur racing, the top racers are all very close together as far as speed, usually within a second or two. If you get caught in a group of guys on the start, the top racers are already a few seconds ahead by the time you are able to make your moves. The start is the only place you can pass 41 other guys in a few seconds. While many already know this, understanding it is another thing… the race can be won or lost in the start. While I didn’t exactly nail all my starts, something I’ve always seemed to do well with is first-lap intensity. It’s easier to pass when racers are out-of-sorts compared to when they are comfortable, have a rhythm, and are using the main lines. I will give credit where credit is due and say thanks to Alex and Mr. Dan Frye for that valuable information.

     

    Going into Loretta’s prep time, I know where I stand, how to improve, and how I plan to make myself better. My costly mistakes from the weekend help shed light on what needs to change and the direction I need to go. I am a firm believer in learning from every experience. I was rusty! But I got the job done and continue to do what many never achieve for the 10th year. Something that may change however, is my path. Like I said in the first blog, nothing is certain in the world of Motocross. Stay tuned for more!

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    Loretta Lynn's SE Regional Championship at MillCreek MX, Photo my Martha @ MEPMX 

    Check in for content along the way and come along for the ride, tap/click the "Follow" button! I’ll see you at the races.

    Scott Meshey #141

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    I definitely want to thank everyone who helps me along this journey. Wouldn’t be able to do what I do without you all! Jimmy, Mike, and Eddie at Cycle Springs Powersports, Chris and the whole crew at Race Tech, Erik at Boyesen, ThumperTalk, Mike at FLY, Brad at EVS, Dien at Acerbis, Rich at EKS (X) Brand goggles, Rob at Dunlop, RoostMX Graphics, Simon at Mika Metals and DT1, MotoSeat, Kevin at Tamer Holeshot Hookup, Gregg at Lynk’s Racing, Andrew Campo, Ricky Renner for stealing my candy, Amish Sam, Momma Meshey, Keith, Amanda, Adam, and Lauren. Also, a huge thanks to everyone at USF Health, especially Dr. Tabatabian and Dr. Welsh for bringing me back to good health! Big thanks to Martha at MEPMX for the awesome shots!

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  2. A key part of the dualsportduo blog is to test parts & accessories for the KTM 690 Enduro R and 701 Enduro platforms and share our experience with you. For the last month or so, I've been riding on a new product from Fasst Company called Impact Adventure Foot Peg. Outside of being really nice over-sized foot pegs, the unique feature is that the foot bed is isolated from the foot peg body by an elastomer whos job is to squelch vibration and shock.

    Here's a side-by-side shot with the stock KTM 690 Enduro R foot peg. I knew they were lasering in the TT logo, but my name came as a surprise. Is that like a monogrammed sweater? I'm going to take crap from my riding buddies forever! :facepalm:
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    Here's a shot of what the elastomers look like:
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    Installed Shot:
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    You can find my full review @

    If you have any questions, hit me up in the comments selection below. What do you think of these foot pegs? Interested in hear your thoughts!

    Bryan Bosch, Steve Claus - #dualsportduo

  3. The key to maximizing your productivity within your workouts is to be hitting the exact duration and intensity levels necessary to address your identified weaknesses.  Each workout’s elements (duration and intensity) are created to stress the body in a manner that creates a stimulation at the hormonal (aka human growth hormone), the aerobic (larger oxygen uptake) and muscular level (development of new muscle) resulting in faster speed and enhanced endurance in a shorter period of time. 

    Please keep in mind that if you push beyond the necessary duration and/or intensity levels, you are pushing the body into a zone that can become counterproductive and negatively affect your speed and endurance – this fine line is the difference between being fit & razor sharp or being over trained, fatigued, sick and/or injuried. 

    Also, by keeping a close eye on your resting heart rate and your body weight in the morning (utilize the Body Analysis spreadsheet – email me), you have two of the key indicators to evaluate how your body is adapting to stress of training on a daily basis.  By keeping detailed logs of your food & body analysis information, you are able to adjust your training & eating habits to turn the body from a catabolic (tear down mode) to an anabolic mode (growth and improvement).  It cannot be emphasized enough the impact your eating and sleeping habits have to your health, wellness and ultimately your performance results. 

    Finally, if logistically possible, please set up an appointment with your physician and have your blood drawn (request a full panel) so that your physician can review the health of your blood chemistry.  By reviewing your blood panel every 12 weeks, we can evaluate the effectiveness of your training, eating and sleeping patterns.  If any of these three variables  become out of balance, you run the risk of becoming over-trained and the associated side effects: fatigue, decreased speed & endurance, irritability, depression, etc. 

    If you have any questions, please don’t hesitate to email me!  Remember, Work Smart, Not Hard!

    Yours in sport & health,

    -Coach Robb, Coaches and Staff

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  4. It's time to open up a can of worms and talk about a hotly debated topic in the powersport community - four stroke cylinder head reconditioning best practices. I've perused the forums and had discussions with people about reconditioning four stroke cylinder heads and there appears to be a lot of mixed opinion and beliefs on what is right or wrong. I'm certainly not going to say my take on the subject is the only way, but I do want to share my opinion, explain the technical details, as well as touch on the machining process. The text below is out of my book, The Four Stroke Dirt Bike Engine Building Handbook, and details why cylinder heads should be reconditioned a certain way. 

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    Whenever new valves are installed in a cylinder head, it is best practice to recut the valve seats since the valves and seats are mated parts, otherwise the new valves are very susceptible to premature wear when run in the old seats. If a major overhaul is being performed, there is a good chance that enough seat wear will have occurred during the engine’s life that the valve seats will need to be recut before new valves are installed. This may be news to you, so I want to provide an explanation of why this is necessary. 

    The term concentricity is used to describe the relationship between the axis of two circular objects. When two objects are perfectly concentric, their axis match up precisely with one another.

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    In the case of the cylinder head, the valve guide axis and the valve seat axis must be as close to perfectly concentric as possible and parallel to one another. Usually, guide to seat concentricity is kept around 0.001” (0.025mm) or even less for racing applications. This is achieved by the factory by using a manufacturing process where the valve guides are reamed first. Then the freshly reamed valve guide bore is used to center the valve seat cutter. Once centered, the valve seat is cut. This process is then repeated for all the valves and results in very good concentricity between the valve guides and valve seats.

    As the engine is run, the valve guides, valve seats, and valve faces will wear. The valve guides will wear from front to back in an oval shape at the top and bottom of the guides. In a cross sectioned view the valve guide will take on an hourglass shape. The guide will become oval as a result of thrust forces stemming from the way the camshaft contacts the lifter bucket or rocker arm. These forces are transmitted to the valves and cause the valves to thrust against the sides of the guides, eventually causing the guides to become oval shaped.

    Once the guides start to become oval shaped, the valve faces will no longer be as concentric to the valve seats as they originally were. When this happens the valves will start to slide against the seats, causing the seats and valve faces to wear. The valve seats will eventually become out of round and the sealing between the valve face and seat will suffer. Installing new valves into oval shaped guides and out of round seats will ensure that the new valves wear out very quickly!

    To ensure the new valves being installed last as long as possible, the cylinder head’s seats and guides must be reconditioned once they are worn out. Complete cylinder head replacement is always an option, but I want to focus on freshening up the original head which is usually a more economical option, but comes with many more variables surrounding the quality of the job.

    There are numerous services offered in the marketplace for valve seat cutting, however, not all valve seat cutting methods are equal in terms of quality. There are hand operated seat cutters, dedicated seat cutting machines, and a few other options to choose from. Selecting the correct seat cutting process and entrusting the work to a competent engine builder is very important. The valve seat cutting process should mimic the OEM process as closely as possible. A concentric valve seat will never be able to be cut without first servicing the valve guides. If the valve guides are out of round then they will either be reamed to a slightly larger size if they are not too oval in shape or they will be replaced. Once any issues with the valve guides are addressed and they are perfectly round from top to bottom, it will be possible to cut the valve seat. Ensuring the valve guide is perfectly round is extremely important since the valve seat cutter is centered off of the valve guide bore.

    Cutting the valve seat concentrically to the guide requires a combination of skill and using modern machinery. The best valve seat cutting equipment in the world is worthless without a good experienced operator running it. There are two main factors which make cutting a seat concentric to the valve guide difficult. To start with, the valve seat cutter uses a pilot which locates in the valve guide. Since the valve stems are very small in diameter the pilots used to guide the seat cutters are also very small in diameter. A small diameter pilot shaft that centers the cutting tool can flex easily, which presents a real problem when cutting the seats. The next issue that arises when reconditioning seats is that often times the cutting tool will try to follow the path of the old valve seat which can make it hard to cut a concentric seat. Couple these factors together with slop within the machine, setup error, and operator error and you can see how quickly things can come out of alignment and you can end up with a poorly cut seat.

    In addition to seat concentricity, the depth the seat is cut to will influence valve spring pressure, shim sizes, and the compression ratio of the engine. All three of these variables will be reduced the deeper the seat is cut, which is not a good thing. The surface finish of the seat itself will influence how well the valve seals. A seat with chatter marks or other machining blemishes will not seal as effectively as a smooth seat. The valve seat width and the contact point between the seat and the valve face are also very important.

    Due to the complexities involved with cutting valve seats on modern four-stroke dirt bike engines, the job should not be left up to just anybody. There are numerous businesses which specialize in valve seat cutting which have both the right equipment and expertise to do the job correctly. I highly recommend spending some time researching and finding a reputable cylinder head machining company when it comes time to recondition your head. If the cylinder head must be shipped off in order to do business with a reputable company, the additional wait will be worthwhile.

    If you found this information helpful and would like more technical info on maintaining your four stroke engine, check out my book, The Four Stroke Dirt Bike Engine Building Handbook.

    Thanks for reading and happy wrenching!

    As always if you have comments or want to share your thoughts please leave a note below.

    -Paul

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    Available at: 
    - Amazon
    - Moto Fix Website

  5. Follow along for a great three day ride!

    I often receive the privilege to ride with people from all the corners of the globe. While living in Peru, one thing I notice is that very few Peruvians have ever ridden in the areas around Cusco where I live and ride. So when I get a chance to show some locals(Peruvians) some of the secrets of their country, I try to do it well.

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    This is what its like to ride in the Andes of Peru...Check it out!

    I met up with the boys in the Sacred Valley on the first day. They told me that they wanted to make another attempt at the trail that we rode two years prior, but never even came close to finishing. It really doesn't matter where you are from, if you are a dirt biker and there is an unknown or impossible trail in front of you,  you want to give it a shot...Maybe not everyone is like that, but most that I run with are.

    The First Day-The impossible trail

    These guys have seen and heard the stories of countless attempts to reach the end of this particular trail. I took a group of some of the best riders from Lima and they fell quite short from the end. I think somewhere in my language, I may have fostered a bit of competition between the guys from Lima and the guys from Arequipa. Sebastian kept asking me if the guys from Lima made it this far. Regardless, I am the only one that has reached the other end of the trail on a dirt bike and neither group has come close. I do look forward to the day when I can cross over and down the other side with another rider or two. Not sure when that will be, but hopefully soon.

    We started up the trail like a herd of deer. The route is super fun with every type of obstacle one could imagine, while taking breaks when someone got hung up. That means it was quite often. The trail was dry at first, then the rain came and put a little bit of extra difficulty in the path. Regardless, we all pounded through hundreds of obstacles in the first couple of hours.
    The trail is relatively short in distance, but time is another measure. The entire trail to the other end is 18 km or about 13 miles. My guess is that we completed about half before throwing in the towel. The constant struggle to keep your wheels on the ground and your sanity intact is not easy. Regardless, the day was a huge success. Smiles all around. Nobody with broken bones, only a few bike issues that we managed to deal with on the trail, and a bunch of sore fellas for the next day of riding. Day one...SUCCESS!

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    Just getting started...

    Day two was also a trail that would challenge each of us. It was a trail that I have done a number of times, but this time was different. We went the reverse direction. I was sure it would make it more difficult, but how much?

    As we started up toward the couple of alpine lakes, we found ourselves exerting a lot more energy than we expected. The toll from the previous day may have had something to do with it. Day two was a loop, so the plan was to reach a certain point of no return and keep on going till we reached the place where we started.

    The weather was cooperative, the trail was formidable, and the good times were had by all. Little by little we made our way over and down to the valley, then up and over another to reach our destination. Check out the videos to see what it was like. Be careful, you might want to come down and join me for a ride after seeing the video...Here is my contact info- scott@motomissionperu.com.

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    The final day on the Cresta overlooking Cusco

    With all that said, we finished the day, absolutely smoked. With one more day of riding to go, we made the plan to meet up for the final day. The guys wanted to ride a bit closer to the city of Cusco. I took them to one of my honey holes. The "CRESTA" I call it. The longest ridge ride that one can imagine. Its filled with nearly impossible hill climbs, drop offs, fast rhythmic sections, and views that are mostly missed due to concentrating on the trail in front of your tire. Another perfect day of riding. Finished off with a plate of local cuisine in the small Peruvian town of Ccorrau and said goodbye to my buds. I can't wait until they come back so we can give it another go on that impossible trail.

    Make sure to follow the blog to stay tuned for the next ride. Also, for more info about Motomission Peru and riding dirt bikes in the Andes of South America, check out our website at www.motomissionperu.com. Also feel free to reach me through TT at Scottiedawg.

    Stay tuned for the next one!

    Scottiedawg

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  6. blog-0894440001474291336.jpg

    Sure, it's fun to put some laps in on a motocross track. But, you'll fall short of your potential if you're not using this key practice law of practicing important techniques separately. This is true for motocross cornering skills as well as motocross jumping skills. Did you know that riding really well requires mastering as many as 55 separate techniques, all laced seamlessly together?

     

     

    If you'd like more of my riding tips, browse my blog here on ThumperTalk or my website. If you'd like to be notified when I post new riding tips, subscribe by clicking the "follow" button (upper right). :thumbsup:

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    Recent Entries

    Hey All, 

    We are the UNLV Rebel MX Club! We're a new student organization at the University of Nevada Las Vegas established in late Fall of 2016. We started as a small group of students that share a strong passion for riding dirt bikes and wanted to share that passion with others and create a way to get people out and riding.

    Getting the club started has been quite a process, BUT it has been worth it and we are thrilled to see it grow!

    Our main purpose for creating this club is to unite the dirt bike and motocross community in the valley, starting with the students at our university as well as members of the surrounding Las Vegas area. Not only do we want to connect current riders, but we also want to get those who have an interest in riding and learning about dirt bikes out there and exposed to this community. How do we plan on achieving these ideas? Great question! We plan on hosting many "Learn to Ride Days" where we will take a few brand new riders out at a time and teach them the basics on the bikes. We have been fortunate enough to pick up some sponsors and funding to buy a club learner bike, bringing our vision closer.  Planning camping trips and super-cross parties is also in Rebel Mx's near future, we are so excited to see what the future holds!

    We want to know who would be interested in joining clubs like these on their campuses and in their community. Let us know! 

    And stay tuned for more info and updates and our hurdles and achievements!!! \m/