Jump to content

dt125r wont start


Recommended Posts

Hello again, not sure if anyone remembers me but anyway my dt125r will not start, ive tried evrything that i can think off.

the 3 main things the bike needs which are spark fuel and compression are there, it just will not start.

what happened was,

the bike was running absolutely fine. with the ypvs jammed open because the pulley was snapped so i had to wedge to pulley

in a stiff position so it wouldnt move. i bought a new pulley and fitted it, reconnected the servo, switch igniiton on and the powervavle would not do that check thing where it makes a zip zip noise or whatever. okay so i kicked it over and revved it to 7k to see if it would start working which it did not (it also started making a wierd clicking noise). then the bike died. so i made sure the powervalve was in jammed open position and unconnected the servo, tried kick startin it and it wouldnt start and hasnt since.

list of things ive tried not in order (maybe more just cant remember)

1.changed coil

2.changed spark plug

3.changed ht lead

4.changed fuel

5.cleaned carb

6.checked and cleaned reeds

7.checked stator,flywheel and all that crap/which is fine (maybe the timing is out, not sure, im not sure?)

8.checked piston and rings, which are fine

basicaly the engine is fine, fuel is getting through, and it has a perfect strong spark.

what else is there? any help would be appreciated, thank you.

Link to comment
Share on other sites

Do you want an ad-free experience? Join today and help support the Yamaha Owners Club.

Hello again, not sure if anyone remembers me but anyway my dt125r will not start, ive tried evrything that i can think off.

the 3 main things the bike needs which are spark fuel and compression are there, it just will not start.

what happened was,

the bike was running absolutely fine. with the ypvs jammed open because the pulley was snapped so i had to wedge to pulley

in a stiff position so it wouldnt move. i bought a new pulley and fitted it, reconnected the servo, switch igniiton on and the powervavle would not do that check thing where it makes a zip zip noise or whatever. okay so i kicked it over and revved it to 7k to see if it would start working which it did not (it also started making a wierd clicking noise). then the bike died. so i made sure the powervalve was in jammed open position and unconnected the servo, tried kick startin it and it wouldnt start and hasnt since.

list of things ive tried not in order (maybe more just cant remember)

1.changed coil

2.changed spark plug

3.changed ht lead

4.changed fuel

5.cleaned carb

6.checked and cleaned reeds

7.checked stator,flywheel and all that crap/which is fine (maybe the timing is out, not sure, im not sure?)

8.checked piston and rings, which are fine

basicaly the engine is fine, fuel is getting through, and it has a perfect strong spark.

what else is there? any help would be appreciated, thank you.

Have you fitted the valve correctly? Sounds like it may have been connected incorrectly the way you say the servo is no longer working.

Link to comment
Share on other sites

Have you fitted the valve correctly? Sounds like it may have been connected incorrectly the way you say the servo is no longer working.

well ive never taken the actual valve out myself so im not sure whether it was fitted correctly, but im pretty sure the valve spins a full 360. ive just got it in the same position i had it before i started playing with it again. which is jammed open:)

Link to comment
Share on other sites

Maybe the PV is jammed...gunged up! with the cables disconnected can you move the pulley by hand?

yea the powervalve moves fine, im not really fussed witth it at at the moment, i only mentioned it because it was what i was doin when the bike died and never started after.

Link to comment
Share on other sites

so it was actually running and then made a clicking noise???

take off the exhaust and see if you can see damage to the piston / rings

yea it was running fine, then i fitted the new pulley , re-connected the servo, PW wouldnt work , then started making a wierd clickin noise, a plastic kinda of clcik thought. ive allready checked the piston and rings, and there fine.

Link to comment
Share on other sites

can you do a compression test?

aint got the tool but done the thumb thing, seems fine. and i feels the same amount of compression it had before it stopped working

Link to comment
Share on other sites

  • Moderator

i'm out of ideas

If you have good compression and good fuel and a good spark I suggest you leave the plug out overnight to evaporate any fuel in there, then re-fit and if possible get a couple of people to give you a good shove to bump start it.

Link to comment
Share on other sites

i'm out of ideas

If you have good compression and good fuel and a good spark I suggest you leave the plug out overnight to evaporate any fuel in there, then re-fit and if possible get a couple of people to give you a good shove to bump start it.

thats what im like, ive done that too, left it overnight 3 nights in a row and done the same thing plus other stuff every day since haha. and ive tried bumping it to, just wont start haha

Link to comment
Share on other sites

Try a new plug.

allready got a new one, mite get another new 1 but dont think it will make a difference

Link to comment
Share on other sites

Power Valve could be rotated wrong and is now totally blocking the exhaust,,,,if so bike will never start

Exhaust off and make sure you have the PV wedged in the open position.

Where is his plastic clicking noise comming from ?

Link to comment
Share on other sites

Power Valve could be rotated wrong and is now totally blocking the exhaust,,,,if so bike will never start

Exhaust off and make sure you have the PV wedged in the open position.

Where is his plastic clicking noise comming from ?

yea its wedged in open position, and im not quite sure where the clicking was coming from, i thought maybe it was the gears in the servo clicking? because the clicking only happened when i re-connected the servo and had the bike running.

Link to comment
Share on other sites

  • Moderator

yea its wedged in open position, and im not quite sure where the clicking was coming from, i thought maybe it was the gears in the servo clicking? because the clicking only happened when i re-connected the servo and had the bike running.

Plasticy clicking was most likely the servo gears protesting. Have the pipe off to check everything is where it should be.

Link to comment
Share on other sites

Plasticy clicking was most likely the servo gears protesting. Have the pipe off to check everything is where it should be.

ye ive dis-connectin the servo now anyway, and yea i have donde, its all in the rite position

Link to comment
Share on other sites

Servo will make clicking noise if its not set up correctly and is trying to work, the valve shouls only turn about 1/4 turn. The fact that it only wont start since you've touched the ypvs def' points to that as a problem. Like someone has already mentioned it could be blocking the exhaust port completely.

Do you have the instructions on how to set it up?

Link to comment
Share on other sites

Servo will make clicking noise if its not set up correctly and is trying to work, the valve shouls only turn about 1/4 turn. The fact that it only wont start since you've touched the ypvs def' points to that as a problem. Like someone has already mentioned it could be blocking the exhaust port completely.

Do you have the instructions on how to set it up?

i never set it up, it was set up before i bought the bike, i just disconected the wires on the servo. and reconnected them when i bought and fitted a new pulley.

Link to comment
Share on other sites

PV can be put in 180deg the wrong way round,,,,,,,,,,yes you can spin it 360deg but it might be in back to front,,,,,if ya know what i mean,,,,,,,,Have a look and see !

So you had PV wedged fully open,,,,,bike ran fine

Then you conected servo,,,,,,bike started clicking and stoped,,,,,,,hasnt started since ?

Now you have servo disconected and PV wedged open again,,,,,,,,,bike wont start

The only thing i can think of is,,,,,,,,the PV may have been all carboned up and sticking,,,,,,then you conected servo but it couldnt turn cause it might of been stuck,,,,,,,the extra load on the servo cause it couldnt turn might have blown something. At the back of the bike, below the seat left side, there is a little white conection box. Is this where the clicking is comming from ??? I forget what this box is called but if its clicking then it is goosed and the bike will not start. Stuck servo might of blown this box.

What is happening now when you try to start her ???????

Ignition on,,,,give her a kick,,,,,,,,,,,,,then what ?????

In Good Detail ! ! !

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Who's Online (See full list)

    • There are no registered users currently online
  • Recently Browsing

    • No registered users viewing this page.
×
×
  • Create New...