2007 standard 4RT 250 was running fine but first, suddenly would cut out when the throttle was touched and now won't start at all. Checked the air fllter, plug, fuel feed from tank (fresh 99 fuel); the plug is wet and it has a spark; doesn't make sense that it won't run. No changes made to idle speed, always used to start on a dead throttle and throttle is fully closed.

Any thoughts please? I can't find anybody local with a diagnostic tool that won't charge me about as much as the bike is worth and reading the manual on diagnostics is gobbledegook to me, I barely understand one word in three... Bring back carbs and points!

Any thoughts gratefully received, cheers.

How long have you owned it?

Make sure the throttle cable isn’t snagged anywhere and properly seated.

Fuel pump wire under the tank connected?

The little grey pipe that connects to the injector hasn’t come off?

Can you get hold of another throttle body to try on your bike?

1 hour ago, lineaway said:

How long have you owned it?

Only had it 5 months. looked v clean when we bought it (suspension, brakes etc excellent), not so great under the tank we discovered, lots of dust and grime on the wiring

14 minutes ago, jrsunt said:

Make sure the throttle cable isn’t snagged anywhere and properly seated.

Fuel pump wire under the tank connected?

The little grey pipe that connects to the injector hasn’t come off?

Can you get hold of another throttle body to try on your bike?

Cable OK, no snags and throttle fully closing. wires reconnected after flushing tank with fresh 99 grade fuel. regret we don't know any other owners

 Do a reset first. Hold throttle all the way open, without releasing kick it twice.

Close throttle and start the bike. No throttle and let it run for a whole minute before you twist the throttle.

 

If that does not work adjust the throttle body one full turn counter clockwise. Try again, no throttle.

Good Luck.

FYI the Idle setting on the 4RT's are quite high 1800 + or - 100 and can be affected by altitude so even if you haven't adjusted it you may still find it is needed.

10 hours ago, lineaway said:

 Do a reset first. Hold throttle all the way open, without releasing kick it twice.

Close throttle and start the bike. No throttle and let it run for a whole minute before you twist the throttle.

 

If that does not work adjust the throttle body one full turn counter clockwise. Try again, no throttle.

Good Luck.

 reset  what ? throttle open no fuel = need free play in cable, so all your doing is clearing the bore out  with air  so hardly a reset is it as, ive been on them 12 yr and have not found what it resets please tell me

Resets the ECU

when mines been running a few hours & is difficult to restart you follow the above procedure & bingo

17 minutes ago, Cookiemonster said:

Resets the ECU

when mines been running a few hours & is difficult to restart you follow the above procedure & bingo

i ask again resets what in the ecu  ?  as i say all that is doing is clearing out the bore of fuel and air mix  

Edited December 9, 20223 yr by on it
add

Someone more technically gifted than me may be able to help

all I know is it works for me

 Yep, the 4rt is very picky if you start it and just ride off cold before the ECU does its thing. It does not happen often, but it sure sucks in the middle of a section.

 

As jonnyc says, could be as simple as the idle been too low.They won’t start or even attempt too if too low. I think it’s anti-clockwise to increase (someone will correct me if it’s clockwise)

Mines the same, when hot if you hold the throttle wide open then push kickstart slowly  3 times, then close throttle kick over & fires into life, I bought mine used, the man I bought it of had it from new, he told me this  procedure & it works.

There is alot of things that has gone wrong with an older 4rt as alot of parts. Start with the simple and work ghrough it. I thought thefe was a thread on the TPS. 

 Also disconnect the kill switch and also a thread on the angle bank sensor.

 The list goes on and on.