I have an 04 RMZ 250 I just re-shimmed the valves and put a new piston in and bike was running great started first kick road it all over the street and golf course. went on ONE ride in the heat and mountains wont kick start at all, and when i was up there i had to bump start it every time I road but still ran strong and normal. Now that i have it home wont kick or bump start. bike has been pulled apart more times than road. please help

Where is it leaking from? If its leaking, that's more than likely why it doesn't run right, the fuel/air mixture is off. Also, I wouldn't continue to run it until the leak is fixed as it may damage the motor from not lubricating properly.

Remove the spark plug, put the bike in fourth or fifth gear then try a jump start but with the key turned off. If the rear wheel locks up when you jump on and release the clutch then the piston has probably seized up OR the kick start-to-clutch hub gearing is messed up. The best thing to do is to remove the left engine side cover and look at the kick start mechanism. You may need to remove the clutch assembly for a full inspection. With the clutch removed the rotor ( crankshaft flywheel ) should turn. If it will not turn then a seized piston, broken cam chain or dropped valve is likely. If the rotor does turn then the kick start mechanism is the problem. Please rate my answer. Thanks!

The rmz and kxf 250 2004-05 is a shame for both suzuki and kawasaki, they worked together to create a 4 stroke engine but failed.The first thing to brake is the waterpump. So everybody has to buy a new waterpump, but not the original one because it was a failure, they all broke and some motors got destroyed. The second thing is the valves and you can mostly reshim them once and then you would have to buy new ones that will also fail after a little use.The last thing that i know of is the camsaft, both the camsaft and valves are weak and wont tolerate any heat and you cant really ride the bike like a real offroad bike.
This is my personal experience.When i bought my bike, everything in the motor had been replaced. Probably because the waterpump failed.Nothing was wrong with it and it was great, great in cold starts and the motor ran great. But after 2 rides 10 hours tops it was hard to start, so i went to the suzuki dealers and they checked the time, set the carbonator and reshimmed the valves.The motor ran for 5 minutes and then was just the same as before. Then they told me that i would have to get new valves.But then i went to check around and everyone that i asked something about these bikes said that i should have asked them before i bought the bike so they could have told me that these bikes will never work properly.And here in iceland it's better for me to throw my bike away and buy a new one, a bike that is not older then 2006.
Its costs 250 dollars just to reshim the valves and set the carbonator.New valves cost around 520 dollars and the suzuki dealership takes around 280 dollars for the work of installing the new ones.

Call a Honda dealer with the frame number on the bike. They should be able to tell you where the bike was manufactured. The valve settings should be the same no matter where the bike was made. There is a proper way to start the engine. Four controls are on your bike to assist in starting. Below are generic instructions.

• The choke, used when the engine is cold. Pull the red knob for choke.
• The " Hot Start " Lever, used when the engine is hot. Pull the lever to lean the fuel mix when the engine has been running.
• The de-compression lever, always used.
• The throttle, used to prime the cylinder, (power valve).

Don't kick, instead, push the kick lever downward. You will feel the back pressure as the piston is going upward on the compression stroke to the point the pressure is great enough that the kick lever "locks up". You are very close to TDC. NOW, pull in the de-compression lever. Push the kick lever a little bit more to get the piston past TDC. Now release the de-compression lever. Give the throttle a 1/4 turn then let it snap closed. A diaphragm, (Power valve), in the carb gives a shot of gas when this is done. DO NOT do this multiple times because you will flood the engine. Leave the throttle closed when kicking. A flooded engine will often backfire. Now give a strong kick through the full sweep of the kick start lever. Quickly get your foot off the kick lever at the end of the kick to avoid any chance of "kickback" from the kick lever. This happens in the case of a misfire, aka > backfire. It can be very painful, and can even break a leg. I am serious about that. Repeat the process (but without the throttle priming), for six kicks. After six kicks go ahead and twist the throttle again for a second priming. A good battery, a clean spark plug, a clean carb and clean air filter will also aid in starting. Note that not all carbs have a power valve. When a power valve is not present you should crack the throttle open only 1/8 inch from closed on each kick.

Put in a new spark plug and check plug wire connections and ECM ground connections.

You probably have weak spark and when bump started the plug sparks strong enough to run the engine.

A weak battey can also cause this. Your ECM needs a minimum of 9V to work. (the ECM gives spark and timing) When kicking over, there is not enough volts to spark. When bumping over the alternator provides the extra volts to start the bike.

Hope this helps!
Rob

Does it feel like yhe kick is even engaging and turning the crankshaft? Are you full stroking/kicking it over or short stroking it? when cold, are you using the choke. I suggest taking a compression test when it feels as if it hs no compression It could be undersized piston, rings, or a simple. good luck

needs a valve adjustment those bikes shim under bucket and are hard to do get a book or bring it to a dealer

sounds like piston rings gone/con rod broken, 2/4 stroke? stupid question but did you check the spark plug/s? if missing/blown off will cause low compression,

To adjust your valves you will need a few standard tools and most importantly a set of feeler gauges. You can buy these at any automotive store. The first step is removing the tank and valve cover to gain access to the valve train. You will see both the intake and exhaust cams plus the tops of the valves. This is where you will be measuring with the feeler gauge. The next thing would be to rotate the motor to top dead center. You will need to remove both inspection covers that are on the side of your ignition cover. This will give you access to the timing marks and to the bolt that allows you to turn the motor over.

Check in your manual as to what direction to turn the motor over. You do not want to turn the motor over in the wrong direction. Turn the motor over looking into the inspection (top) hole. You will notice a mark on the fly wheel. When you see this mark come around, look up at the cams. There should be two punch marks on the cam gears that line up with the gasket surface towards the outside of the head. At this point you should be at top dead center compression. Check the lobes of the cam, they should not be touching the valve buckets. If they are touching the valve buckets, this means that you are 180 degrees out of time. Rotate the motor 180 degrees and then start to measure.

After you measure the clearance between the cam lobe and the valve bucket, you will want to write that down. You will then need to check your numbers against the spec's provided in your service manual. If you are outside the specified range, you will need to remove your cams and replace the shims. There should be a chart in your manual that will help you to decide what shims you will need to bring you within the safe range. When dealing with the KXF250 or the RMZ 250, you want to make sure you use the correct shims. There are two types that will fit these bikes, but only one is the correct shim. Shims come both forged and sintered. They look the same until you put them under a magnifying glass, then the difference is very clear. The forged shims have a smooth surface, while the sintered shims have very small cavities. Using the sintered shims will prematurely wear the coating off of the valve stem. This will shorten valve life and cause the valves to go out of adjustment sooner.

Now, after replacing the shims, all that is left is to reassemble your machine. Pay closer attention to the instructions in your owners manual. Always double check your cam timing with what is recommended in the manual. Do not start your bike without turning the motor over by hand first. If you feel it is unusually hard to turn over or it will not turn over, you probably are off on your cam timing. Once again, do not try and start the bike. Go back and retime your cams.

if its making a rapping noise its the valves ,possibly contacting the piston