MotoCross | Moto x | Super Moto | Motocros | Enduro

KX250F Valve Adjustment

2009-11-18T04:40:00.000-05:00

Replace The Piston And Rings.

2009-11-18T04:33:00.000-05:00

How To Whip A Moto X Bike

2009-10-21T08:29:00.001-04:00

Change and maintain your clutch.

2009-03-04T13:52:00.000-05:00

Clutch Tip.

2009-03-04T13:50:00.000-05:00

Clutch Tip

How badly do you want to win? It sounds like a simple question, but it involves a number of improvements on your bike. They might be simple tweaks individually, but taken together they make the difference between first and second place.

One of the most important things you can do to tweak your bike is to tune up your clutch. Every time you engage or release the clutch, valuable seconds may be spent or lost on the lap’s time.

The clutch has been a pivotal part of the forward momentum formula for as long as bikes graced the pavement (or dirt), but really haven’t changed much as far as utility is concerned. It gives you access to the different gearing that will give you an advantage over your rivals when changing speeds or angles of attack.

Slipping clutches will penalize you, so this is something to guard against. It will drag or slip and cause your rivals to scoot past you. If you find yourself in this situation, it’s time for a tune-up; no doubt about it.

Number 1: You’ll need to install new clutch plates; the first thing to do is soak them in gear oil. This will make certain that they are completely lubricated. The easiest way to do this is to put them in order in a Ziploc bag and then fill the bag with the recommended grade of gear oil. After a short period of time, they will be ready for installation.

Number 2: By all means, be sure the entire bike is clean. Any outside contaminants stand an easy chance of getting into your bike’s insides if you are not vigilant with what happens outside it. Now back-bleed the rear break. When you apply to pressure to the calliper, you can move the brake fluid into the line.

Step 3: Don’t try to loosen the bolts willy-nilly. Loosen them in a rotational matter one at a time. It’s best to do this once the whole assembly is completely cooled off. Once this is achieved, disassemble the remainder and take out the stack of cooked plates.

When all the clutch plates are out, check the condition of the clutch basket. Change it if needed

Step 4: Install your new clutch plates. Starting with a fiber plate, make sure that each plate has an even coat of oil, slide the plate into the basket with either side facing out. The next plate in should be metal, and it’s important that it goes in with the flat, machined surface facing out. Proceed with this process until the last fibre plate has been installed. The height of the stack will be nearly flush with the edge of the basket.

Step 5: Reassemble everything in reverse order and you should be good to go!

Hot tip: We recommend that you change the clutch springs every second or third clutch changes.

Motocross Suspension Set Up Video

2009-02-27T11:01:00.000-05:00

Suspension Setup

2009-02-27T09:46:00.002-05:00

Suspension Setup

As you know, there's a lot more customization that goes on with a dirt bike than a pocket rocket. Why? The riding conditions are different and if you want to be competitive, your bike has to fit you like a glove. One of the first things to tweak is the suspension. Right out of the box your bike's compression clickers and the rebound setting might be set anywhere.

The best place to start is to set these two settings in whatever the manufacturer recommends as “standard”. This is a good starting point. If no setting is recommended, just choose a middle setting. This is what an average might employ.

The rear spring may or may not be right for you. Did you buy your bike second hand? In that case, it might not be standard for you model; the former owner might have customized it. Take it for a test ride. Does it feel right for you? If so, you're on the right track. Otherwise, before you start tuning the suspension to your liking you might want to consider installing the standard spring.

You'll want to set your rear shock's static sag. Follow these steps to configure the preload.
1.Locate the locking ring and loosen it.
2.Adjust the main ring to adjust the shock's preload.
3.With the bike elevated so that the back wheel is not in contact with the ground, take a measurement from your axle nut to a reference point on the bike somewhere above it.
4.Now set the bike back on the ground.
5.Measure the distance between the axle nut and the reference point.
6.Subtract one measurement from the other.
7.Adjust the ring until the difference is about 25mm of sag.

Now it's time to set what's called the laden sag or racing sag.
1.Stand the bike it an upright position and write down the vertical height.
2.Put on all your race battle gear and assume your best attack position on the bike.
3.Have a friend take the measurement now on the fully loaded bike.
4.Do the math again as before. Now adjust the preload again to get it between 90mm and 110mm.

Going through these set-up routines might seem to be a hassle but they are worth the effort. No factory setting is going to satisfy every motocross racer. If you've been in the game for any time at all, you know that the devil is in the details. Who can afford to throw away even the tiniest of advantages?

Moto x

MX Training Journal

Motorcycling Gearing.

2009-02-15T10:34:00.000-05:00

Motorcykling Gearing

When the factory engineers develop a new bike, one of the most important things they have to do is optimize the gearing. They use their own test moto track with their own test riders. They use average riders and the track is an average, generic track so what do they end up with?

Average gearing. But when you think about it, it's all about mass marketing. That's a good thing though. If they manufactured a myriad of choices, delivery time would slump and manufacturing costs would be passed along to us. A large number of riders will be content with this set-up, but more aggressive racers want a custom gearing configuration. Let's look at some factors to consider.

To Gear Down or to Gear Up; That is the Question

This is really a personal preference but part of it depends on the tracks you ride on. Does it have a lot of long straight legs where you can get up a head of steam? Lots of tight coffee-cup turns at the base of steep jumps?

Gearing up: this is achieved by by either using a smaller rear sprocket or a larger countershaft. The net effect is to add more speed while lowering the final drive ratio.

Gearing down: achieved by using a larger rear sprocket or a smaller front sprocket. Net effect? It raises the final drive ratio, while lowering speed. Great for climbing.

But What is the Final Drive Ratio?

Alright, it's time to apply that schoolhouse math. To arrive at the final drive ratio, divide the number of teeth you've got on your rear sprocket by the number you have on your countershaft.

But what does the number tell you? It's the number of times your countershaft will turn during one complete rear wheel rotation. A smaller number tells you that you'll experience higher RPMs for a certain speed and a higher number is the opposite. Now it all makes sense, right?

Riding at Altitude?

If you're planning to ride at a high altitude, not only should you get there a day or so early to acclimate and avoid light-headedness, but your ride needs modification too. Higher altitudes mean less engine power, so gear down to compensate.

Clutch Implications

An interesting side effect is that the lower your gearing, the less you'll have to use your clutch. Why? Because your engine will be more responsive and run freer.

What About the Power band at Higher Gearing?

Basically, it's the opposite of what we just discussed – you'll put a bit more wear on your clutch; but on the other hand, your engine will be easier to control.

And Lower Gearing Power band?

In a low gearing configuration you'll find yourself shifting much more often to stay in the sweet spot. It's just the opposite of taller gearing.

Be Your Own Pit Crew

Be ready to fine-tune your gearing configuration on the fly without having to change the chain. Put together a starter pack to haul along with you to the track. Include a spare rear sprocket that's two teeth larger than the current one and a countershaft that's one tooth less. The tooth ratio of rear sprocket to countershaft is ½:3.

NOTE: As a rule of thumb, one tooth change at a time in gearing is the max.

Wear and Tear: Your Sprocket Should Match Your Chain

If your existing chain is worn and you use it with a new sprocket, you'll be throwing your sprocket money away because the sloppy chain links will wreak havoc with the new teeth.

Of Rear Sprockets and Countershafts

The smaller your countershaft is, the faster your chain is going to wear. It's a friction thing. Say you decide to ride with countershaft that's one tooth smaller. Your best bet is to use your standard counter coupled with a new chain with an extra link and a rear sprocket that's three to four teeth larger. But avoid the temptation to lengthen the chain with an extra master link; that's asking for trouble!

motox

MX Training Journal

Wash your Bike.

2009-01-26T06:46:00.000-05:00

Elementary Bike Maintenance: a Good Wash Job

A clean bike is important. How important? Are you a rider who thinks that checking your oil level is the holy grail of bike maintenance? Well, that's important, but the detailing of your ride is critical. By examining the bike at this level, you'll spot problems before they arise. Race day is the last time you want a failure – especially one that you should have seen coming.

As you know, that mud can and will get everywhere. Begin the cleaning disassembly by removing your seat and cleaning it separately. Since you are going to want to give the bike a good spraying down without giving yourself any headaches, it's a good recommendation to insert an exhaust plug.

Another thing you'll want to do is remove the air filter and put a cover over the air box. Acerbis probably has a good quality one for your model. This presents a good opportunity to inspect the filter itself. Is it time for a replacement or cleaning?

Now you'll want to give your bike a good soaking with a quality detergent before any real scrubbing takes place. This will loosen the mud and grit and minimize scratching due to scrubbing. Teepol Gold is a great detergent for motocross mud. The water pressure from the jet setting on your hose attachment should do a good job.

There are certain areas of your bike which should NOT be subjected to a high pressure spray. Bearings and any electrical connections should be avoided. They are engineered for water contact but not for high pressure.

The underside of your bike is an area which is subject to the most mud and debris build up. A good spraying will dislodge this and make soap-sponging a breeze. Be sure to turn off the fuel cock before laying the bike over on its side before you do this, however.

From the bottom of the bike, work your way forward and pay attention to the front forks and seals. “Spray and inspect” is the name of the game here. You don't want to compromise the seals from too much water pressure.

Once the bike is clean to your expectations, go ahead and use a light oil anywhere it might be of benefit, such as around dust seals and fork seals. Open the drain on the base of your carburetor and drain any moisture that might have accumulated during the washing. Replace the air filter. Secure your seat and wipe down the entire bike with a chamois cloth to eliminate spots and streaks.

Now is a good time to crank up your bike and let it idle to dry off all engine and electrical connections. This is also a good time to do your lubing chores. Oil your chain. Try a product made for bicycle chains called “White Lightning”. This lube encapsulates debris and flakes it off before it can cause friction damage to the links or gears. Use Armor All or a similar product to protect tires and plastic components from UV damage.

With proper care, your bike will serve you well and hold up in the most stressful of situations.
moto x
MX Training Journal