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Bombproofing your bike.

Imagine this scene.  You're riding like you have never ridden before. Heck you're positively flying. Then it happens. You hit a bump and dump the bike. Hey it happens and you have enough lead to get back on and keep going.  Then you notice the damage.  Your clutch lever is broken, your tire is flat and your kickstarter has gone AWOL. You're out of the race. On a scale of 1 to 10 , 10 being the crappiest this situation rates as a 20, easily.

Well don't worry. Up here in beautiful British Columbia, the collective minds of Team Grizzly have seriously trashed their bikes and have come up with some suggestions on how to bombproof your bike. (Bulletproofing sounded too wimpy.) You basically start in the garage from the first thing you do. And you keep doing it until you sell your bike. I will tell you the basic threats and how combat them.  The five horsemen of doom are: Dirt, Water, Mud, Crashes and Bad Mechanics. You don't need much to keep your bike running.  Bearing grease, loc-tite, gasket maker, silicone sealant, time and determination.

Enemy No. 1: Dirt.

Dirt on the outside is fun, dirt on the inside is not even close to being fun. It gets into the workings of your bike and causes premature wear and tear. There are ways to keep the dirt on the outside.

One of the big ways for dirt to get in the engine is the same way air gets in. Service your air filter regularly. Clean out the larger clumps of dirt from the airbox, before you remove the air filter. Clean the filter with a degreaser and squeeze the dirt out. Gasoline works well but clean the filter outside and away from flame. Do not wring the filter since you might put some tears in it.  Squeeze it instead. Then wash the filter in soap and water.  The degreaser removes the oil and the soap removes the dirt. Let the filter air dry for a day or two. Then re-oil it with foam filter oil and grease the base of the filter with axle grease. Also put some grease around the hole which holds the filter in place. This prevents dirt from entering the carb. You can use a dual stage air filter such as UNI. They're thicker. The outer part traps larger particles, while the inner part is finer and traps the finer particles. Also UNI's have a better base for applying grease to seal the filter to the airbox. You can also seal the air boot connections between the airbox and carb with silicone sealant. Don't throw away the airbox lid. The lid serves to divert dirt away from the airbox. In dusty conditions over oil your filter and grease the inside of the airbox. (Hell, grease the inside of the airboot too.) Use filterskins or women's ped. On some four strokes, oil the filter the day before you go riding. Some strokers have so much vacuum on the intake that fresh oil is sucked in and can foul the engine.

Dirt can also enter via the exhaust port. Another tip is to place a bead of hi-temp silicone around the exhaust port to seal the engine to pipe connection. The vacuum created by the engine can draw in dust. And there is still another way for dirt to get in. Make sure that there are still hoses on the carb. If those vent hoses go missing then there is another route for dirt to get in.

Dirt can also enter when working on the bike. Make sure the bike is clean when you work on it. Heck make sure your hands are clean from dirt too.  Wrap some plastic around the top bar when your working on the engine when it's still in the bike. There can be lots of dust trapped in the wiring around the top bar. Keep dirt away from the filler caps, funnels and fluid bottles. Also make sure parts are clean before installing them. Give the top end a good cleaning before you reinstall it on the bike. (The guy at the bike shop may have not read this article.) You can also make sure all the vent hoses are in place and that the ends are cut at an angle to prevent clogging. When you're cleaning the bike, never let spray from a pressure washer hit the bearings, seals or engine intake and exhaust ports directly.

On the forks,  check all the oil and dust seals. Make sure the fork boots are preventing dust from getting on the sliders. Watch for dings on the sliders. This can cause the seals to fail prematurely so more crap can get in the forks.

For the drive train you can get an O-ring chain and self cleaning sprocket. This'll prevent premature wear of the chain and sprockets. Also oil the chain before you go riding and before you wash it. Oiling the chain before cleaning will help repel water from the chain.

Wash mud off as soon as possible to prevent the acid in the mud from eating off metal and to prevent it from hardening. This is especially important with Washington state mud/concrete. You can also spray the plastic with WD-40 or PAM cooking spray to prevent mud buildup.

Enemy No. 2: Water.

This is where you get to play with the silicone sealant you bought. Seal the ignition system. I recommend the proper gasket along with sealant. Also seal the grommet where the wires are fed into the engine case. Also seal the joints in the airbox where the airboot joins the box and the carb. Make sure the drain at the bottom of the airbox is clean so the water drains faster. Also you can get some heatshrink tubing and place it over the electrical connections above the engine.

Other places where water can ruin things are in the suspension. Grease bearings, pivots, bushings and axles. It prevents rust and makes it easier to disassemble. Also regrease bearings soon after a dunking. Also brake fluid is hydrophilic. (It loves water) Bleed and replace after a wet ride.

At water crossings, ride in single file slowly. If there is a risk of drowning the bike then get off and walk the bike across. This will raise the bike. Also put the cylinder at TDC, shut the bike off and close the throttle If you do flood the bike you should remove the spark plug, and roll the bike over onto it's handlebars.  Shift it into gear and begin to paddle the rear tire to cycle the engine. (In with the good air and out with the bad.)

Water from the outside isn't the only threat. So is water from the inside. Use distilled water for the bike's cooling system. Regular tap water has minerals in it that will form deposits and insulate the engine, preventing efficient heat transfer. Vinegar works well at flushing out the rad.

Dirt and Water's Illegitimate offspring: Mud.

You can stay home. (Not a chance!)

Otherwise you can try to keep the mud from accumulating and causing you to crash. It gets into the cracks and weighs down the bike. It also pack into the tread of the tire turning a set of knobbies into slicks. Also mud can cover grips, pegs and controls. This'll give you control problems

Make sure your grips are in good condition. Oversized handguards can keep a bit more mud off the grips. Also file the footpegs to offer more grip. Pack scotchguarded foam between the skid plate and engine. Spray PAM or WD-40 onto the plastic. Mud won't stick to an oily surface. If you can afford it run solid brake rotors and metallic brake pads. Also run soft terrain tires with a wide spacing on the knobs. Increase the preload. Mud can increase the weight of the bike.

Enemy No. 3: Crashing

One of the best ways to avoid crashing to to ride in control. The first thing about to do to keep control is to keep the controls working. Tie wire and glue grips to prevent spinning. Also replace grips when they become too worn. Also adjust the levers so that you have full use of them while sitting or standing on the bike. You can wrap a little hockey tape around the levers to give a little more grip. Keep the foot pegs sharp so that boots have better grip on them. You can also apply some grippy material to the side panels so that your knees can grip the bike better.
If you can't help crashing then buy armor. Barkbusters, radiator guards and skid plates are worth the investment. With skid plates, place a piece of scotchguarded foam between the engine and the frame. This way mud won't accumulate there. Use aluminum handlebars, with bark busters. You can also drill levers 1 ½ in. away from the end so it breaks at the weakest spot when you crash. Also wrap a layer of teflon tape around the handlebar before you mount the perch. This allows the perch to spin. Chamfer (round off with a file) the edges of the bar clamps, since the action of moving up and down actually cuts the bars. Another trick is to attach brake snakes to the rear brake and shifter. This'll prevent sticks and stuff from getting between the lever and engine and prevents it from ripped out. Other pieces of armor to consider are discguards and a heavy duty chain guide. You can install a 1-way valve to prevent gas from spilling from the fuel vent hose.

Brake Snake Installation.

Get some cable and some cable ferrules. Wrap one end around the frame. Then drill a small hole in the lever at the end. Do keep in mind that a lever will break at the weakest point. Drilling a hole behind the lever will create a weak spot there. Then feed the other end of the cable through the hole and back into another clamp. Crimp both clamps down after making sure you have enough slack to make sure the controls still work properly.

Flats are another problem. To prevent flats, use heavy duty tubes. There is a bit more rubber in them so that they resist puncturing. You can also try to double up the tubes. Take an old tube, cut the stem out and slit the tube open so that you have a rubber ring. Then wrap a semi inflated tube with the band. You can also increase air pressure. This will prevent pinch flats. But keep in mind that increased air pressure can cause control problems. You can also fill the tire with tire goo to help seal any punctures. If you like wrestling with tires you can try foam inserts. These take some heavy duty tools to work with and may have a tendency to breakdown at high speeds. Another option is a semi-crescent mousse. This has the benefit of being easier to install and can be adjusted to suit the conditions since the pressure is varied by the tube in the mousse.
Rim care is also a important part of preventing flats. Make sure the rim is free from serious nicks and scratches. When installing tires for the first time, take the rubber band around the rim and throw it away. Then wrap several layers of duct tape around the rim. this provides better protection for the tube. Also when installing a tire, make sure the rim lock is secure. A spinning tire can cause the tube to shear off the value stem. Before mounting the tire check in the inside of the tire for nicks and sharp objects. When you're done, check the tire is at a proper pressure and replace the valve stem cap.

Bad Wrenching & Bad Mechanics

It's not that people go into the garage in deliberately wreck their bikes. They just don't know any better when they work on their bikes.

Most common problems:
Air filter not seated - This allows dirt to get into the engine.
Lost bolts - Can cause all sort of problems
Overtight nuts and bolts - More problems, especially when the head get stripped from removal attempts.
Loose nuts and bolts - They can fall off during riding and cause all sort of havoc.
Bad chain care - Chain can snap or cause the sprockets to wear prematurely
Unneeded repairs
Bad washing - Water can get into the bearings and blow the grease out. Then the bearings fail.
Hop ups - Can increase the strains on an engine and cause premature wear on the engine
Loose Spokes - Can saw through the hubs and the rims, causing tire failure.


You can strip down the bike yearly to inspect for worn parts. This is an excellent activity to do over the winter months. Consider your manual for the bike a bible, and consult it often. Basically follow the maintenance schedule set out in your owner's manual or repair guide:

Clean air filter daily or once its get discolored from dirt.
Check compression.

80-125’s every 10hrs.
250’s every 20hrs
500’s every 30hrs.
Check the chain tension and lube the outside even on the O-ring chain.
10-20hrs regrease the suspension and headstem.
Replace gear oil every 4-5 hrs.
20hrs. inspect the reeds for cracking.
Lube the cables after 10-20hrs of riding.

Bonus section: Bombproofing the Rider.

Muddy Conditions:

Wear neoprene gloves, they offer better grip.

Tape an old lens to your visor to protect against flying roost.

Duct tape the tops of your boots.


Wear windproof gear. Use a dickey to protect your neck.

Prepare a lot of goggles. They really fog up.


Hydrate or die is no joke.  Stick to water or sports drinks and drink lots. Look for fatigue, dizziness and headaches.


Get extra goggles and switch them at the gas stop. Just keep them in a ziploc bag until needed. If you can afford it, try to get a new pair of goggles since scratch goggles are bitch to see out of. Use clear lenses, not the yellow ones. If somebody tells you otherwise, just smile and nod. You can use vaseline on the foam on the goggles to keep dust out like you do with your airfilter. Baby oil will work in a pinch but it can run down into your eyes. Foam filter oil will work, but you can guess that the yuck factor will be very high. Cleaning the lens with fabric softeners or Armor All can eliminate some of the static electricity that can attract dust.

Contents Copyright (C) Michael Fodor 2012.