Leaking forks is one of those things that plague off-road riders. Many think that if your forks are leaking then it's time to replace the seals, but that is not always the case. Before I go any further, however, I need to put in a disclaimer here. If your forks have been leaking for a while and you have been ignoring it, or it's been a while (maybe never) since the oil has been changed, then you should have the forks gone through no matter what. Fluid loss can lead to unstable handling, and worse, damage to the internal workings of your forks. Also, over time as things wear, your forks build up grime inside so they need to be cleaned and maybe have wear parts replaced. Don't ever attempt to clean a leaking shock seal using this method, shocks are charged with high pressure nitrogen and should only be serviced by someone that knows what they are doing.
Now, having said all that, back to what I was really writing about. If your forks have just started leaking, don't assume it's time for seals. More often than not, a leaking seal is caused by very small bits of debris getting caught between the seal and the fork leg. With a little patience the debris can usually be cleaned and you are good to go. So the burning question in your mind right now is "how do I clean the seals?". Okay, maybe that is not the burning question, but if you are still reading you are least mildly interested, so here you go. The first thing you want to do is make sure the outside of your forks are clean. Using a brush, water and some liquid dish soap carefully clean all the dirt, oil and other grime from the the fork legs paying particular attention to the wipers (the part that looks like a seal that you can see from the outside). You should probably remove the fork guards before you wash just so you can really get in there and clean all the way around. Once you have the forks clean, put the bike on a stand and get something to sit on. The key to this is taking your time, so if you are squatting and uncomfortable you will most likely want to rush through the process. Using compressed air, blow away any remaining dust from the wiper and fork, then with a flat blade screwdriver, carefully pry the wiper down working your way around the upper fork tube, remember to go around the tube and work it down instead of trying to pry it completely away from one side. Once you have the wiper out of the way you have access to the actual seal. You may be able to see the spring clip, it might be tempting, but don't remove the spring clip! Using non-chlorinated brake cleaner (you can use chlorinated but it stinks and doesn't evaporate as quickly) liberally spray the seal area to wash out any dirt or grime that might be hiding up in there; following with compressed air to help blow out debris and evaporate the brake cleaner. Don't go crazy with the compressed air, you don't want to push dirt up through the seal and into the fork oil. Now that you have the area clean it's time to clean the seal itself. Remember, leaking is normally caused by dirt getting between the seal and fork leg. The last thing you want to do is introduce more dirt, or push the dirt up inside the fork. I have heard of a variety of "tools" used for the next part; feeler gauges, business cards and even wrapping the area in black tape and compressing the forks (essentially pushing the dirt into the fork). Personally I don't like any of those for a variety of reasons. I prefer to use either a piece of plastic like you find on product packing or even better, Motion Pro makes a little plastic tool that works really well. Using your tool, carefully slide it between the fork leg and the seal. With a little sawing motion, work the tool around the leg. I like to start off doing about 1/8- 1/4 of the way around the leg, pull the tool out and wipe it off. If you look carefully you will probably see very small dust particles in the oil on the tool. Wipe your tool with a clean paper towel or rag and keep repeating this process until your tool comes out with just clean oil and no particles. This is the patience part, you may have to go around several times before you get it clean. Relax, have an adult beverage if that helps. Once you have cleaned the debris, wash down the outside again with brake cleaner and compressed air. Remember to clean the inside of the wiper as well. Put the wiper back into place, take the bike off the stand and compress the forks several times. I like to clean the fork legs with a clean towel and brake cleaner after each compression. If the leak stopped you are good to go, but if one or both of the seals continues to leak, either you didn't get them clean or it's time to replace the seals and have the forks serviced. Keep in mind that if you ignore the problem it will only get worse over time. Also take a good look at your front brakes, if you pads have been fouled with oil they should be replaced. Once you have done all that and you have metabolized your adult beverage get out there and ride the thing!
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Spring is in the air! You can always tell because you start seeing FB posts about the Desert 100. After participating in both the Poker Runs and The Race I have seen some pretty scary crashes as well as some frustrated riders. One of the things that has always amazed me as you walk around camp is how many bikes are in pieces. I don't know if it is just because people wait to have their machines worked on by the vendors that are there (some of whom are top notch) or because they haven't really looked at their bike all winter and just realized/remembered that it needs work. Either way, this is not your best move. The biggest problem with working on your bike in camp is the blowing dust. Every year I have been there the wind blows like crazy and almost every year the dust is also blowing like crazy. When you open your bike up (any part of your bike) you are exposing it to dirt and grit. Getting dirt in any part of your bike that has any sort of lubricant is very bad. Dust has a nasty way of sticking to oil and grease. Bearings+Dirt = failure and lots of money out the window.
It's hard when there is still snow on the ground to get yourself motivated to get the bike out and see what it needs, but do yourself a favor and start now. Here are some things to look at and get taken care of so you are ready for the big weekend. Grips: seems simple enough and not a big deal, but good grips can be the difference between blisters or no blisters. Steering stem bearings: Put your bike on a stand (probably a good idea to have someone else hold the bike so it doesn't fall), grab the fork legs and push/pull, if you feel any play you may have a bearing issue. At the very least if you haven't done it recently it's probably time to clean and repack your stem bearings. Wheel bearings: With the bike off the ground check for any side to side slop. If you do have play in the wheels double check that they are actually tight and don't have loose spokes. A bad wheel bearing at mile 60 is probably not going to end well. Spokes: Again with the bike off the ground check for loose or broken spokes. This is particularly important on small bikes. Missing spokes, particularly when riding the desert, usually leads to more missing spokes pretty quickly and a short day. While you are at it, make sure your wheels spin freely and don't have any wobbles. Chain and sprockets: Make sure your chain is adjusted properly. Once it is adjusted, pull out on it horizontally at the very back of the rear sprocket, if it pulls away from the sprocket it's probably time for a new chain and probably sprockets (your new chain will last longer if installed with new sprockets). Check your sprockets, look for any "hooking" (particularly on the front) or sharp teeth. Brakes: Check your brake pads and rotors, if your pads are near 3 mm or so replace them. You don't want to find out your brakes are worn on some rocky downhill section. Fork seals: This always seems to be a big one. If your seals are leaking, don't assume it's time for seals. Motion Pro makes a nice little plastic tool for about $5.00 that helps get seals clean and stop leaking. If you have not done this before, Youtube is your friend. Having said that, if your seals have been leaking for a while or you haven't changed the oil in your forks in recent memory it may be time to take care of it. Having your suspension in shape can be the difference between getting through the whoops and ending up in a sage bush on the side. Remember to put your bike on a stand and crack the bleeders, be careful if you haven't done this in a while the little screws can go flying sometimes if there is a fair amount of pressure. Rear shock: This is one of those things that is easy to ignore and takes tons of abuse. If it hasn't been serviced in a while it's probably time. They do lose pressure over time and the oil needs to be changed. Carburetor: If you are careful about not using ethanol gas, use a cleaning product occasionally like Sea Foam and run the bike every so often you generally don't need to do much with your carb. Having said that, if the bike won't start, or is hard to start, only runs with the choke on, won't idle, etc. It's probably time to pull the carb and clean the jets (and everything else) or even have it rebuilt. Valve adjustment: This is one of those things that is often ignored because they can be a pain to check and adjust. But, making sure your valves are in spec can save you lots of headaches. Also, depending on how much time your bike has on it, replacing the timing chain periodically is a very good idea. Like your drive chain, the timing chain can and does stretch. When this happens it throws the valve timing off slightly, which in turn can make the bike hard to start, lose power and in some cases jump timing. Usually when that happens you are in the middle of nowhere and the only way out is uphill both ways. Air filter: A clean air filter is absolutely crucial. I strongly recommend you have at least one if not two extras. If you do the poker run your filter will be dirty by the end. If you plan to race the next day you will either need to clean your filter or put on another. The biggest problem with cleaning while you are there is getting it to dry somewhere out of the dust, but warm enough to actually allow it to dry. I have seen lots of guys pushing their bikes because their filter plugged with dirt, don't be that guy. Tires & Tubes: Good tires can be the difference between washing out in a corner or making it up a hill. Just because your tires still have knobs on them doesn't mean they are still good. Front tires tend to start losing side lugs long before they look worn in the middle. Rear tires can lose lugs all over the place. Tubes also should be looked at carefully when changing tires, some people recommend always changing the tube when you change the tire. I don't personally belong in that group but if the stem is rusted at the base, lots of dingle berries on the tube that don't rub off easily, creases or small tears; replace the tube. Do yourself a favor and get a heavy duty tube. I have talked to people that won't run a heavy tube because of the weight. That's all fine and good, but keep in mind this desert riding/racing not supercross. Pinch flats can ruin your day. Last but not least is oil. I put oil last because of all the things that people neglect or ignore on their bikes this is by far the worst. Most modern bikes only hold about 1 quart of oil (some even less). Which means that it doesn't take long for that oil to get dirty. Once that oil is dirty and full of carbon it starts wearing things out prematurely. I have seen perfectly good engines ruined in a short period of time because the oil was let go too long. What kind of oil, synthetic vs. mineral, etc. etc. is up to you. Put keep in mind, just because synthetic oil doesn't start breaking down as fast as traditional it still gets dirty. Keep in mind that by taking care of things early you can save yourself lots of trouble and money later. Not to mention you can spend your time hanging out and having a good time rather than losing bolts in the dirt. But, remember, no matter how much you plan things can still go wrong with your bike or you (a crash for instance) so be sure you have water, a little food and a way to communicate. Most of us are not professional riders with a full support crew, so be smart and be safe! One of the biggest problems with small engines is the age old problem with hard starting. Back in the old days, before electronic ignitions, it often was the result of points being out of adjustment which threw the ignition timing off and all the other fun problems that went along with that. But points are (thankfully) a thing of the past unless you are into vintage machinery. Since the 1980's almost everything is electronic ignition of some sort. Because of that innovation having to adjust timing on a small engine is a thing of past. So, why is it that small engines get hard to start? There are lots of things that can impact an engine's starting ability, but the two most common problems come down to maintenance. In many cases the problem lies either in the fuel system or in the valves, sometimes both. Today's fuel is typically a some sort of ethanol blend; nothing new there. But, what most people don't understand is that ethanol is a form of alcohol which is water based. Think back to your high school chemistry class, "like dissolves in like" alcohol mixes better with oil based products than water, but over time it separates and then begins to break down. Once fuel begins breaking down it starts forming corrosion on the metal parts, particularly the brass jets. The jets get plugged and don't allow fuel to flow through and wa la, your machine get very hard to start and often will not idle. The best solution is to buy non-ethanol fuel, however depending on where you live that is not always so easy. So, if you know your machine is going to be sitting for a while, drain the carburetor and fill it with Sea Foam, or even diesel. Just remember to drain the fuel bowl before trying to start it the next time.
Valves are the other common culprit for hard starting. The reality is that valves go out of adjustment with use. Often we don't think about adjusting the valves because modern passenger engines (like in you car) use hydraulic lifters that compensate for wear and don't generally need to be adjusted. You do occasionally see hydraulic lifters in small engines but not very often. When valves go out of adjustment it is the opposite of what you might expect. Instead of the clearance between the valve and lifter getting loose, it actually gets tighter; to the point where the valves are not actually closing completely. This prevents the engine from building proper compression (particularly when the engine is cold) making it very hard, if not impossible to start normally. Tolerances on modern engines, particularly high performance engines, are very tight so a few thousandths of an inch can be the difference between starting and not starting. As spring approaches and you start thinking about getting your equipment out of the shed keep these two things in mind. A little bit of maintenance can save hours of cussing. |
Rob BlazinaArchives
June 2023
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