Was riding down th road at 60 & when I backed off the throttle it would'nt slow down.

Was the vehicle checked with a scan tool & road tested with it?

What does the data tell you?

Look at freeze frame data when it slows down

Only thing to guess at from here, without the vehicle to
look at data,would be the fuel pump is seizing up & your
loosing fuel pressure

You have to set up your test equipment to pick up things when
it acts up

May have to smoke the intake,exhaust & evap system

Vacuum leaks may happen only after it is hot & driven some

Could be the evap purge opens & you have leaks down stream

We only need to know about the vehicle,nothing else,certainly
not the financials,if that is an issue, your not likely to find or fix much

Has the throttle and return cables lately (like ever) been lubed/oiled?

Also, put some grease on the end of the handlebar where the throttle sleeve rides.

Try grabbing the governor arm coming out of the side of the engine where the throttle linkage comes from, can you manually slow the engine down with that? Is it stuck?

follow the throttle cable all the way down to the engine. Have some one move the throttle up and down to see if the throttle plate is opening and closing all the way. You can loosen the screw holding the throttle cable and move it back and forth to see if it will allow the throttle plate to open and close correctly. It may have slipped when the assembler tried to tighten it.

First take mass air flow sensor off and clean it with a non-chlronated brake cleaner and reinstall it and see if that helps.Then if that did'nt help check the fuel pressure because low fuel pressure will do this, make sure its within the specs which is 55-60 psi with key on and engine off.Also there are several sensors that will cause this to like crank sensor, throttle position sensor.

Yes you were in throttle by wire limp home mode. What DTCs are set?

Buy a good floor pump with a gauge (see "How to Buy a Bike Pump," under Related eHows). A small, frame-mounted pump is useful only for roadside repairs.

Understand that it's normal for most tires to lose up to 10 pounds per square inch (psi) per week. This does not mean you have a slow leak.

Look on the tire's sidewall for tire pressure recommendations. Don't exceed the maximum tire pressure listed.

Inflate your mountain bike's tires to 40 psi for dirt riding. You may wish to inflate your tires to 50 to 60 psi for city riding.


Inflate your road bike's tires to 100 psi for road riding. Some road tires have much higher psi ratings. However, 100 psi will provide a good mix of performance and comfort.


Inflate your hybrid bike's tires to 60 to 70 psi for city riding.

Check your tire pressure before every ride

Here's my take on tire pressures and when they need adjusted, I wrote this a while back for someone with a Honda African Twin, so this should help:


Manufacturer's recommendation – Short distance city riding below 100kph. Light off-road use ie. Small rocks, gravel. If the weather/road conditions vary a lot.


30% above recommended pressure – High speed road use. Long distances in warm weather on good quality roads. Go 40% if the conditions are the same but the bike is fully loaded with carriers.


15% below recommended pressure – Short distance riding in cold winter temps. Short distance on wet roads. Off-road, average gravel/rocks and some wet mud.


40% below recommended – Slow off-road riding in very loose dirt, sand, with lots of rocks. Tires will heat up quickly if the pace is picked up which will loose grip and cause accelerated wear.


60% below recommended – Very slow, loose dirt, deep sand (dunes). If tires slip on the rims you need to increase pressure.


My mantra is all about keeping a close eye on tire pressures and adjusting them to suit the conditions rather than keeping strictly at the manufacturer's settings. Starting out my riding career on a BMX, tire pressures can be the difference from landing a perfect jump and falling on your face. Therefore, with a motor attached, it is even more important to get it right – personally I think the 'feel and grip' is more important than the pressure number – regardless if that causes tire wear.


Hope this helps and you vote for me :)

Check your linkage at the top of the carb,the throttle link couldve came loose at the throttle shaft.

if you push it that far you are choking the motor
back the throttle back down to slow and try to start the mower if it starts go back to fast but not all the way to choke