Dirt Bike FAQ

Yep, alot would depend on his height and his riding experience…

if little to no experience, it would be best to start him off on a mild 4 stroke trail bike, like a Honda CRF80/100/150F (not R) or a Yamaha TTR90/110 or a Kawasaki KLX90/110 if those aren't too small for him. or if he is taller, CRF230 or TTR230 which are mid sized height wise but tend to be on the heavier side. these are all air cooled, older designed and bullet proof engines with moderate (at best) brakes & suspension but great bikes to learn how to ride on.

if he has some experience and is more agressive, something like a CR, KX, RM, YZ 80/85/100 or CRF 150R small wheel or expert (depending on his height) which will have all the performance upgrades including suspension & brakes.

if he is 5'6" or taller, he might be able to fit a full size bike…

again, little to no experience, XR, KLX, WR, CRFX 250

or if some experience and/or agressive, CRF, YZF, RMZ, KXF 250…

I would advise to start off used to save yourself some money as he might quickly outgrow or loose interest… then once he finds what really fits him, then you can always upgrade to newer…

Why even bother with a small engine? As you learn to ride and improve, you're just going to need a bigger bike. If you get a 150cc, you might as well get a 50cc and soup it up. If you're going to get a smaller engine, get a 125cc two-stroke engine (i.e. a CR125, YZ125, etc.).

If it were me, I'd get a late-model four-stroke. The power delivery is smoother and they're easier to ride. Check out the Honda CRF250 (or at least the CRF230). Yamaha, Kawasaki, Suzuki, and KTM all make excellent bikes. Some people only buy certain brands (mine are Honda and KTM), but they are all such advanced machines that any of them will be more than enough bike for you. Get at least a 230cc, but only if you're willing to need to buy a bigger bike in a year.

For the record, I ride a 2003 CRF450. If I had bought a smaller bike, it simply would not have been powerful enough, and I'd have had to buy a bigger bike. But I've been riding for over 20 years, and so I knew I needed a big bike.

They all do. Are you looking for specific size motor or brand?

This is just one place of many that can help http://www.minibikeoutlet.com/ You can modify the engine as much as you want, like increased compression, bore it out and new exhaust, the bike rear tire can only be 10" tall and some times the front tire can be a little taller depending on the rules you run under

If the bike has a battery, check that first. motorcyle batteries are fragile and one that has not been charged or maintained for a few years is most likely shot. remove the batt. from the bike and clean the + and – connections. make sure the water is up to the top line on the side of the batt. case. with the filler caps removed put it on a low amp charger, not more than 10 amps. if after 10 min. to a half an hour you don't see bubbles, replace the batt. sometimes a stone dead batt. will lose it's polarity and not take a charge. sometimes you can bring them back by running 2 heavy jumper wires from a good batt. connect the jumpers pos. to pos. and neg to neg from the good batt and the one you are trying to charge. put a charger on the good batt and again watch the batt to see if it starts to bubble/gas. if the batt will not take a charge or has been frozen at all throw it away and get a new one and put it in the bike. after you have a known good electrical source, or the bike doesn't have a batt, move to the next step.
pull the sparkplug and connect a known good plug to the plug wire. with all switches turned on ground the plug to the engine and kick it over a few times. it's a good idea to do this in a darkend or shaded area as it's easier to see the spark. to ground the plug, put the metal part, about were the wrench goes, against the bare metal of the engine. if you don't have any spark you have more problems than I can help you with here. you should see a blue spark between the electrode and the plug ground….little bent over piece at the tip of the plug.
now, turn the gas off. remove the gas line/hose from the carb and with some gas in the tank and the hose in a small clear container, to catch the gas, turn the gas on to reserve. gas should come out of the line and into the container. if it does not, the valve/petcock needs to be removed and the small screen and the valve needs to be cleaned….the gas tank also. after you get a small amount of gas in the container look to see if it is clear without anything floating in it. if this is ok replace the line on the carb, if not clean the gas tank. if there is an in line filter on the gas line make sure that is clear. the gas should be off at this time.
now remove the air box cover and/or air cleaner. this should be free of debris, you would be amazed at the things i have found in the air cleaner on bikes that have been sitting….acorns, nests all sorts of crap. if this is ok and the air cleaner is servicable, next step.
turn the gas on, with at least a gallon in the tank, and hit the float bowl area of the carb with the handle of a large screwdriver. don't hit it any harder than you could hit your upper arm without it hurting. watch the carb for a minute or two and check to make sure the carb is not flooding. if it's flooding you will see gas coming out and dripping off of it. if this happens turn the gas off and remove the carb for repair. if all is ok, next step.
with the spark plug still removed, pour about a pop bottle cap full of clean gas down the sparkplug hole. replace the plug and with all switches and the choke on, kick the bike over. if it has spark it should start, assuming the internal mechanical parts of the engine are sound. if it starts and dies, pull the plug and try another capfull of gas. if it starts and dies again try kicking it half a dozen times with the choke off and the throttle wide open. if it still won't run remove the carb for repair. if it starts and stays running check that it idles smooth and accelerates without popping or having flat/dead spots. if it runs ok throw 3 capfulls of a good fuel system cleaner into each full gas tank for about 4-5 tankfulls…..now go ride the bike. if the bike runs rough, won't idle or has flat/dead spots on acceleration, remove the carb for repair.
even these simple carbs can turn into a nightmare for someone that doesn't know what they are doing. if the carb needs repair and you don't know what you are doing, have someone that does take it apart.
be carefull, you are working with gas, and it can catch fire and burn you.

If your riding in the wet, this is quite common, check your pipes for kinks mate, check your airfilter is clean, if your riding in mud, you shouldnt have a K&n air filter better off with a 2stage foam filter, keeps out mud more.

Also handy if you clean your carb, special unleaded can help with this, also other products, as someone else said, might have a bad batch of fuel.

Make sure your choke is off.

If its a 2 stroke, make sure you have the right petrol and oil mixture.

If its 4 stroke, make sure theres some good 4st oil in the engine

All Jap manufacturers recommend 32:1 for all their 2 stroke engines.

1924 in britain or south england.it was called a scramble velocetto was the bike it had a 250cc two stroke engine. 80 bikes started 40 finished.

Firstly, any dirt bike will probobly be too tall for you at 5'2" as they have lots of clearance, but then dirt bikes are light as buggery in the 125 to 450 cc range so if you can reach the ground, it should be allright. those pit bikes or pocket rocket bikes are for kids (i wouldn't let my kids on though). they are a toy and are useless for anything. you cant register them, they cant handle real rough stuff and they are shockingly built and engineered

secondly, gpx250r's are road bikes, and would be perfect for you. I am 6'4" and 130kg and it even handles me (but it looks like cruelty to small motorbikes)

I believe you want to know how to shift a dirt MOTORcycle. When to shift is mostly by feel and engine load. How to shift is a tricky thing, The clutch really only needs to be used to stop the transfer of power to the rear wheel. Once the motorcycle is moving you can shift by just going up or down on the shift lever, being that the gears in the transmission are strait-cut they can be up-shifted or down at any time. The use of the clutch is mostly for starting, stopping and any time you need to stop power to the rear wheel. If you've never done this before just be cautious. After you've dumped the mc a few times you'll want to buy a mtn bike, you can ride it almost anywhere and it won't annoy the neighbors.