Jump to content

dt125r running a bit funny


This post is 4684 days old and we'd rather you create a new post instead of adding to this one. You can't reply in this post.

Recommended Posts

hi

i have been reliving my youth by buying bikes i used to have back in the day

my recently purchased dt runs a bit bit funny ive had it a few weeks but have been concentrating on paint work

now thats finished its time to get it running right

i have not tried to sort it yet but thought id ask for a few opinions before i start

first off it wont idle

second its bogs down a bit when you rev it

at higher revs its very crisp but the revs drop down slowly as if your closing the throttle slowly

on the move it does go very well tho

anyone got any ideas or suggestions before i pull the carb to bits

cheers

bry

Link to comment
Share on other sites

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

A few posts on here for the same problems. I have the same problem but im working through them.

check that the throttle cables free and not stuck from either dirt/age or routed badly under the fuel tank. 2 adjustments screws which alter the idle speed and throttle response. carb MAY be dirty and may need cleaning and the big one to miss is make sure the air filter housing is sitting correctly with the carb or it will give a lot of the symptoms your getting.

Mines carbs been cleaned and its now sitting at 1000-1200 and needs a fine adjustment but as yet i havent had a chance to do it yet.

Hopefully you will get other help from more experienced people on here.

Link to comment
Share on other sites

  • Moderator

Test the joints when its racing away. Spray WD40 on the periphery of the cylinder base joint, the cylinder head joint, the joint of the carb to reed block manifold and the joint of the reed manifold to engine. See if the spraying affects the engine speed / tone

Link to comment
Share on other sites

2 stroke's

Clean air filter,,,,or get new one

Clean exhaust,,,,,de-clog the thing

Clean carb,,,,every single bit of it

Clean filters in tank and the pipes to the carb

Check for good spark

Set the carb to factory settings, to start with

There is many things that can describe what is happening your bike,,,,,,,,,,,,,,,,carb settings,,,,,type of exhaust,,,,good air filter.

Best thing to do is get manual

And before ya start any of the above Check Compression,,,,,,,,it should be minimum 100ps or more.

Patience is key

Best of luck

Link to comment
Share on other sites

You beat me to it Oldgit ;)

Link to comment
Share on other sites

2 stroke's

Clean air filter,,,,or get new one

Clean exhaust,,,,,de-clog the thing

Clean carb,,,,every single bit of it

Clean filters in tank and the pipes to the carb

Check for good spark

Set the carb to factory settings, to start with

There is many things that can describe what is happening your bike,,,,,,,,,,,,,,,,carb settings,,,,,type of exhaust,,,,good air filter.

Best thing to do is get manual

And before ya start any of the above Check Compression,,,,,,,,it should be minimum 100ps or more.

Patience is key

Best of luck

Daft question, but when you took your carb off did you take the carb off with the fuel pipe attatched to the carb? or did you leave the pipe attached to the petrol tap? I only ask because theres a wire gauze filter that sits inside the spigot on the carb that can get blocked.

And not many people realise that theres one there, just a thought.

Link to comment
Share on other sites

Daft question, but when you took your carb off did you take the carb off with the fuel pipe attatched to the carb? or did you leave the pipe attached to the petrol tap? I only ask because theres a wire gauze filter that sits inside the spigot on the carb that can get blocked.

And not many people realise that theres one there, just a thought.

Yep pipes off carb and leave on fuel tap.

Nearly sure the older DT's dont have that steel mesh filter in the inlet spigot but the newer DTR and DTRE have it.

Thoroughly clean carb everywhere and he should find it.

Link to comment
Share on other sites

Yep pipes off carb and leave on fuel tap.

Nearly sure the older DT's dont have that steel mesh filter in the inlet spigot but the newer DTR and DTRE have it.

Thoroughly clean carb everywhere and he should find it.

I found one in mine, and mines a 92, mikuni flatside/ flatslide someone correct me there, T132, could be off a newer bike mind, dunno.

Link to comment
Share on other sites

  • 3 weeks later...

hi

bit of a follow up i took the carb off to change the main jet to suit my end can

it was a bit dirty so gave it a quick clean when back together it started and ran loverly and crisp until it leaked fuel everywhere

so carb off again to give the floats a tweak

put it back together fired up no leaks but no bottom end revs or idle again

im wondering if there may still be crap in the pilot jet

cheers

bry

Link to comment
Share on other sites

  • 4 weeks later...

If it struggles to idle then id check the pilot jet, the main jet sounds fine if it revs past a certain rpm.

Just give the carb a good going over with compressed air or similar to remove all the crud and make sure theres no blockages in the fuel lines as fuel may have been sitting in it for some time and block it up. There isnt too much to a 2 stroke so you should be able to pin point the fault sooner. =D

Link to comment
Share on other sites

×
×
  • Create New...