Why does my Yamaha Moto 4 250 not start?
Bought an old Yamaha (Moto 4 250) and the thing won’t start. It will start with choke full on – but close choke and it’ll die. If you give it gas – it dies. It will take throttle with choke on (and smoke like a chimney). When I first got it the thing would start periodically – but again soon as you give it throttle it died.
What was the bad news about the Yamaha 350 Moto 4?
The good news is that the engine ran. The bad news is that it was a total travesty. The jets in the Warrior carb were too rich for a stock setup, so it ran poorly and smoked. Also, the cam chain in the engine was rattling and the starter clutch was going out. Decision time: Do I scrap the project or order some parts?
How do you ground a Yamaha Moto 4?
I ground it down smooth with the surface as seen below. Bolt end ground smooth. I was then able to take my impact driver and remove the bolts manually. Removing the bolts with an impact driver. Once ground smooth, the bolt turns easily. Then it was time to install everything.
Are there parts to rebuild a Yamaha moto4?
Sloanman or Elast. Do either one of you know or tried yet to get the parts to rebuild a motor on one of these 86 Yamaha Moto4’s 250? Are they hard to find and if you are the parts higher than normal?
When did the Yamaha Moto 4 come out?
The introduction of the Yamaha Moto 4 in 1985 occurred when the ATC or three-wheel design dominated the all-terrain scene. Back then, ATCs or all-terrain cycles already had powerful engines but were not the safest or most stable to ride over uneven terrain.
The good news is that the engine ran. The bad news is that it was a total travesty. The jets in the Warrior carb were too rich for a stock setup, so it ran poorly and smoked. Also, the cam chain in the engine was rattling and the starter clutch was going out. Decision time: Do I scrap the project or order some parts?
What is the owner’s manual for a Yamaha Moto 4?
Owner’s Workshop Manual shows the way of assembling and disassembling of an ATV according to factory standards. This manual empowers the user having a little mechanical knowledge to detect problems prior to taking assistance from experts. It shows the troubleshooting process through photographs, diagrams, and illustrations.
What are the specs of a 1985 Yamaha Moto 4?
The ’85 model features a snorkel air intake and front and rear racks. It comes equipped with a 45-watt bulb headlight and a 7.5-watt taillight. The MSRP of the 1985 Yamaha Moto 4 is quite obscure.
The introduction of the Yamaha Moto 4 in 1985 occurred when the ATC or three-wheel design dominated the all-terrain scene. Back then, ATCs or all-terrain cycles already had powerful engines but were not the safest or most stable to ride over uneven terrain.
What’s the top speed of a Yamaha Moto 4?
The Yamaha Moto 4’s top speed is between 45 to 50 mph – this is true for 225-350-cc models in good working conditions. The YFM200 registers a lower top speed between 33 and 37 mph. These figures may still go up if you modify your Moto 4 Yamaha.
What kind of engine does the Yamaha Moto 4 have?
Yamaha produced three other engine displacement versions for the Moto 4, namely: the Yamaha Moto 4 225, 250, and 350 – these new versions came with manual transmission and 4WD options.
When did the Yamaha Moto 4 350 come out?
Although the Yamaha YFM200 started the Moto 4 series, its sibling Yamaha Moto-4 350 became the designated Moto-4 model from the time it hit full production in 1987 until 1995. The Yamaha Moto 4 350 or YFM350ER eventually became the prototype of various Yamaha models such as Warrior, Raptor Big Bear, and other YFM designations.
How to troubleshoot Yamaha ATV starting problems?
Diagnosing ATV starting problems is relatively easy to do, and there are multiple tests you can run to find the problem. You want to start by testing your battery, of course.
What should I do if my Yamaha starter is not working?
If nothing happens after flipping on the kill switch, remove the front plastic cover to expose the battery, starter solenoid, starter relay and other electrical components. A battery test is the best place to begin. Set your volt/ohm meter to DC volts, and connect it across the two battery terminals.
Can a bad spark plug cause an engine to misfire?
If you have separated spark plugs, unplug each coil to see if you can find out if any cylinders are not responding. Replace if you find one faulty or have a trouble code stored for one ignition coil. 2. Bad Spark Plug The second most common cause of a misfire is bad spark plugs.
Why does my ATV backfire when I start the engine?
To put it differently, when the ATV engine receives an overly rich mixture of air and gas, the excess fuel in a cylinder doesn’t get burned in time for the exhausting process of the engine cycle. As soon as exhausting starts, the cylinder’s exhaust valve opens, which immediately igniting the unburned fuel because of the influx of extra air.
What causes an engine to misfire on all cylinders?
Low fuel pressure will cause a lean mixture in your engine which will result in misfires on all cylinders. If you have trouble codes for misfires on all cylinders, you will want to check your fuel pressure. 5. Injector Problem Another problem, which was more common five years ago, is injector problems.
Why does my Yamaha ATV have no start?
A “no start” problem on your Yamaha ATV can be attributed to one or a plethora of electrical problems. Fortunately, there are many simple tests you can do yourself with relative ease.
Why does my ATV keep sputtering and misfire?
Another reason why your ATV may be sputtering is because of the ignition coil. If the ignition coil doesn’t send enough of a spark into the spark plugs, then your ATV will misfire and sputter. If you suspect that your ignition coil isn’t working correctly, then you may need to take your ATV to a mechanic.
Low fuel pressure will cause a lean mixture in your engine which will result in misfires on all cylinders. If you have trouble codes for misfires on all cylinders, you will want to check your fuel pressure. 5. Injector Problem Another problem, which was more common five years ago, is injector problems.