Mechanic Tip of the week …. archives

Mechanic Tip of the week….
This week is about warpage. There are a few items on your bike such as the cylinder head, case halves, clutch plates or rear brake disc that needs to be checked for warpage when you work on them. My shop has an expensive machinist flatness plate but you can get excellent results at home. Window glass is very flat if you do not see any distortion when you look through a window you can count on that piece of glass being flat enough to check your bike parts. Might want to do this when the wife is not home as she might not understand why you are holding a engine case up against the window with one hand and a feeler gauge in the other.

Mechanic Tip of the week.

One thing all of the new 4T motocross bikes have in common is a quick access valve cover with a reusable gasket. There is a good reason the manufactures made it very easy to check your valve clearance. They want you to check it regularly ! Once your gas tank is off the valve clearance check only takes a couple of minutes. But what does the measurement tell you? It lets yo
u identify which valve is getting tight then after you are ready to replace the second smaller shim for that valve its time to send your head to Pro Circuit to have them restore your head. How often to check? If you ride a 250F on the rev limiter check every 7 hours. Where as a beginner putting about on a 450F every 30 hours or so should work. Whatever your interval is, the important thing to remember is a valve failure in your bike could be very $$$$ expensive to repair and if it happens on the face of a jump it could cost your life.

Mechanic advice tip of the week. (2 items this week)
For Woodland Motocross Park and Riverdale use an air filter skin. and change your filter every ride. The filter skin adds a layer of protection as the fine ash and silt will try to ruin your cylinders nikasil coating very quickly.
Tip 2 increase the frequency of your linkage and steering head lube schedule. The summer time 25 to 30 rides between lubes should be reduced to less then 15 rides between lubes at Woodland and Riverdale.

Mechanic tip of the week….
Isn’t it great that the manufactures have a quick access cover for changing clutches between motos. The steel clutch plates in your bike are cut out in a stamping press so one side of them has a radius edge and one side has a sharp edge. If you place all the radius edges facing inward toward the center of your engine the clutch will engage faster and smoother.

Mechanic Tip of the week.
If you left your MX bike tied down in your vehicle every second you were not riding it. It would not take long for your fork springs to get sacked out. The same is true with your valve springs. If you store your bike when the engine is not on the compression stroke at least a couple of valve springs are being compressed for days at a time. So at the end of your riding day slowly push down on your kick start lever until you feel the compression stroke and stop. In this position your valve springs are fully extended and should last longer.

Mechanic tip of the week….
This week Snap rings, circlips and retaining rings. What could we possibly need to know about this stamped out piece of steal? Believe it or not there is a load side and a keeper side to these rings. When a snap ring is made a die cuts it out of a sheet of metal. As the die strikes the metal it leaves a slightly rounded edge. a new die would leave a pretty good edge and a worn die will leave a very rounded edge. When you install a snap ring place the rounded edge against the load so the sharp edge is on the outside of the load to get the best grip on the shaft or bore to keep from slipping. If both side are good and sharp and one side has a smoother finish place that side against the load. I am a firm believer in replacing snap rings with new especially with transmissions.

Mechanic Tip of the week…
Modern gasoline goes stale fast. How fast you ask?  In a highly scientific controlled laboratory A.K.A the shop.  Draining carburetor float bowels after only 3 days one can see the tiniest hint of the fuel starting to turn yellow.  Why is this important?  From that point until the gas turns into a solid crust goo that clogs your carb is only a matter of time.  If you are not going to ride your bike for more then 1 month drain the carburetor and the gas tank completely. Use the gas in your car, lawn mower, or leaf blower . But I have a fuel injected bike you say. For you fill up your tank  with non ethanol fuel if you can find it and add in a product called Sta-bil. Once every 3 weeks go into your garage and start your fuel infected bike to keep the fuel moving past the filters and injector while its in storage. When you take your bike out of its winter hibernation drain all the gas and put in fresh. Your bike will not be happy running that several  months old gas with Sta bil but your lawn mower will use it just fine.

Mechanic Tip of the week……
Your wife may not agree but a much better use for a hair dryer on a cold day is to warm up a tire before mounting it on a rim. Usually you will need to warm up a tire twice during a tire change when it is cold out. A warm tire is significantly easier to mount as the rubber becomes more pliable.

Mechanic Tip of the week…..
When you need to open up your engine to check your valves or put in a fresh piston or any other reason. One will always find bits of dirt in the wire harness and cables under the tank. Murphy will ensure that dirt will fall into your engine and do expensive damage. It only takes a minute to put a bit of Glad wrap around the area and protect your engine while you are working on it.

Mechanic Tip of the week… .
O rings and Seals
Of all the new parts you put on your bike O rings and seals are certainly high on the list of things are easily damaged during installation. Most of the carnage these seals see is from sharp edges and installation techniques. Here are the tricks to install new o rings and seals.
First inspect the shaft or bore that the seal is going to be installed on. Buff out any burrs or sharp edges. For shafts with a raised step the seal has to climb over to get into
position use a bit of electrical tape wrapped around the step to protect the seal. If a seal has to pass over threads use tape there also.
Second lubricate the seal with the same fluid that the seal will be used with or a compatible seal grease.
Third if it is cold in your shop use a hair dryer to warm the seal.
Last gently install the seal do not force it. Try to install it without tools, if you have to use tools be sure they don’t have any sharp edges. For Fork seals use a seal bullet to protect the seal and buff out any sharp edges on the oil transfer holes near the top of the slider.

Mechanic Tip of the week….
This week is about warpage. There are a few items on your bike such as the cylinder head, case halves, clutch plates or rear brake disc that should be checked for warpage when you work on them. My shop has an expensive machinist flatness plate, However you can get excellent results at home without the expense. Window glass is very flat if you do not see any distortion when you look through a window you can count on that piece of glass being flat enough to check your bike parts. Might want to do this when the wife is not home as she might not understand why you are holding a engine case up against the window with one hand and a feeler gauge in the other

Mechanic Tip of the week….
Wet or dry ? No not your martini we are talking about your bike’s hardware. The bolts and screws that hold your bike together. Most of the time the correct answer is wet. What is wet hardware? you say. Most of the hardware on your bike is made from a steel alloy. It usuallys threads into an aluminum part. Aluminum and steel don’t play well together when it comes to disimiler metal corrosion. You may have seen this when you have removed a case bolt and found it covered/caked up in a white powder. To install a bolt or screw wet is simple one puts a bit of blue loc-tite on the treads and a bit of grease on the shank and thread it home. If you are installing a bolt into a nut the is held in place by a plastic part such as your airbox or gas tank or lower radiatior shroud coat the shank and threads with grease or a anti-sieze lubricant. So what hardware should you keep dry? Any bolt or screw in which a electrical bond must be of good quality or any bolt you remove every ride, such as yur seat bolts which access your air filter.

Mechanic Tip of the week….
This week lets talk about whacking things with a hammer. When you go to the tool store one sees that most punch sets are made from hardened steel. These are really not the best choice for most things that need to be beaten on your bike. Using a steel punch can often do a lot of damage. A much better choice is to go to a quality hardware store such as Ace and buy some brass rod in a couple different diameters. Brass makes a fine drift and reduces the amount of damage you can do with it. As always be sure to wear eye protection when whacking things with a hammer.

Mechanic Tip of the week….
Ever watch a movie and a bomb is thicking down the time till it explodes then the hero comes in and disarms it at the last second. Racing engines are just like that. The are ticking time bombs, both 2 and 4 strokes. The 2 strokes just do less damage to your wallet when they blow. Racing engines have a finite life and you can be the hero that keeps them from devistating your bank account. But like in the movies you need to have a timer know how much time you have. That timer is an hour meter. You see them on a lot of bikes in the pits, you need one too. By knowing how much time your engine has on it you can make good decisions to greatly reduce the risk of it from blowing up. This link has a suggested time based maintenance recomendations which may fit your racing profile. https://isobareng.wordpress.com/motocross-service-intervals/

Mechanic Tip of the week….
The bike that is going to win this weekend at your race will almost certainly have all the parts put back on it in the proper place without any left on the work bench. Here are 4 easy ways for you to do the same. (win that is !!!)
#1 raid your wife’s cabinet and relocate to your shop a large cupcake pan or better yet one of the type for baking multiple mini loaves of bread. with a bit of tape you can label it just like the picture and organize your parts as you remove them.
#2 The screws holding your case halfs together are often of different lengths and one can do some expensive damage putting a long case screw into a short hole. Simply take a piece of cardboard and a marker draw out a basic diagram and using an awl punch out holes in the cardboard and place each screw in its representative spot.
#3 Get a sharpie and mark parts that have a left or a right side such as as bolt that may have a clearance issue if put in with the head on the wrong side.
#4 before you take something apart take a picture of it. That way you will see exactly where the proper cable runs are or shim stack ups when you put it back together.

Mechanic Tip of the week….
Just 1 minute. That’s it, 60 easy seconds. Your bike is asking just one additional minute of your time. What can I do in just 1 minute? You can do a quick check of all of the bearings on your bike that are not part of your engine. With your bike on a stand and both tires off the ground, secured so it will not fall over.
Here is how to do a quick check of your bearings.
1. To check your front and rear wheel bearings. Do this, Place one hand on your frame or handle bars and the other at the 12:00 position on your tire gently push and pull the wheel sideways while looking at the hub where the axle enters it. Even the tiniest bit of up or down movement at this point is a sign of a worn out bearing.
2. Next slowly rotate your wheel and feel for any unusual drag not associated
with your brakes. Any notchy feeling is grounds for a bearing replacement.
3. To do a quick check on your rear suspension linkage. Start with your chest over your rear fender and use both hands to grip your rear wheel at the 12:00 position. Gently lift the wheel upward if you feel any movement before your shock starts to compress you may have worn linkage or shock bearings.
4. Now place your hand on your back tire at the aft end at the 3:00 position try to move it side to side and watch for any movement at the swing-arm.
5. Next its time to look at the front end.. Position yourself in front of your bike and grab the bottom of both fork legs and pull them toward you. You can feel 2 different items here the bushings inside your forks and the bearings in the steering head. You should be able to discern which if any of these is providing any movement felt. If you need to, have someone pull on the bottom of the fork legs while you place a finger alongside the bearings to feel for any movement. be sure not to turn your handle bars when your fingers are next to the bearings or you can get a nasty pinched finger. Next with your fingers out of the way slowly turn your handle bars side to side any notchyness is a sign of worn bearings.
If you are ever unsure of how any of these items should feel to you, simply swing by your dealers showroom and do the same test on a new bike. Hay it only takes a minute.

Tip of the week.

I bet your familiar with the law of gravity and maybe a few other laws from physics class. But this weeks tip is about Murphy’s law. Discovered in 1942 the great Murphy discovered that if one leaves an opening into your engine while you are working on it. Something that can hurt it will defy all odds of falling anywhere else besides into your engine. To combat this natural attraction be sure to clean the area above before opening up an access to your engine and then cover that opening with a plug, cap, tin foil, plastic bag or anything else that will keep out what will surely complete Murphy’s equation of “That which will happen will make your wallet bare” As an example there is always dirt that hides in the wire bundles along the frame above your valve cover. I like to take some tin foil and wrap the area around the wires and frame before I pull off the valve cover to keep the dirt out.