Hey all I have got a dt 125 r 1996 when riding it will not go over 6k sometimes a little bit more just sounds like it is losing the spark every now and then but is fine all revs up to 6k it does it in neutral but allows me to get to 8k I have recently done crank seals and it run fine after that so checked all magneto an stator they all look fine I'm very stumped now can any one help

There is a video on you tube showing what I mean. Ill post the link soon

I have changed spark plug

Cleaned the carb

New coil and lead

Checked all wires for wear

If any one can help would be much appreciated

I would check the fuel supply, TANK / Petcock/ In neutral an engine requires just a whif of fuel to redline , under load, it requires good flow..

Thanks for your reply I will have a look at that today it is so strange here is a link not my video but exact same problem

http://m.youtube.com/watch?v=FRy6i2PnUkk

I think I have found the problem thepower valve had moved and was bouncing in and out just a bit of fine tuning

Nope the power valve was only part of the problem any one else got any ideas I cleaned the tank and Petcock all looks to be working fine

Have you had carb off ? its just not reving out clean, then dies then picks up . deffo lack of fuel, back out air screw a turn , see if that clears it, . hows air filtre..?

Yep had carb off and been soaked in carb cleaner and sprayed compressed air through all jets and passages air filter is clean no air leaks and I have played about with air screw no luck there have gone all the way to 2 and half turns out then back in to 1 and half turns were it runs its best I'm completely stumped now when it misses the power valve pushes out a little bit if that makes sense don't no if it is meant to to that (no servo fitted just pinned open) also tried another carb did not make a difference

That's why I think it is electrical :s

On another note if any ones got the pulley for the power valve for sale pm me please

A pinned open power valve will give you no bottom end,,,[ power] have you looked at exhaust, is it clear i,,

Yer I no I am in process of doing the power valve servo just need the pulley got everything else and I live on long straight roads so usually higher up in the revs so it dont bother me no bottom end and yer I have had a look at the expansion chamber looked pretty clean but did not look in silencer could that course this problem it's got a full dep sytem on it

Thanks so much for your replys

Still stumped new carb new coil new spark plug cap new reeds new ignition new plug checked exhaust

Any one in Kent fancy a bacon sarnie and brew all day haha

What jets are in the carb " and what is standard for the model,,,?

Standard is 210 and runs rather hot so put a 240 in it which runs lovely spark plug a nice brown colour

Think in going to have to pay some labour as I'm not getting any where I'm tinkering on it all day every day

Aha" pull the 240 main, and put back the 210, thats the cause, when you open wide throttle ,its the main jet that comes into play,

your bogging the motor, How do you know it was running hot " , just by feeling the engine" read my post on spark plug experiment.

and temperature,,

Okay I will try that today was running fine with 240 before this started and I knew from the smell the heat to touch and temp gage nearly on red usay sits just off of cold.

I see what your saying about bogging motor as took petrol tank off yesterday started bike and it was ticking over for like ten minutes with no petrol tank has never done it for that long before

Thank you for your help ill keep you posted and have a read on your spark plug and temp post

Was not the jet tried a 210 and done exactly same thing :s

Could the power valve make the bike do what it's doing? As the power valve pushes out of the barrel only by couple of mil but were I haven't got the servo it should not be moving at all?????

I have basically the same problem. I'm quite sure it's electrical, but based on this thread i figured it could maybe be something else...

(the thread: )

Looking forward to seeing what could cause this... Almost ordered a new stator today but after seeing this thread started to reconsider

Hey glad to see I'm not te only one with this problem

And I've read that post about ten times now don't really help me to much thanks tho

It might be going to a shop tomoro if I can get a deal on some cheaper labour if it does ill post what the problem was if they find it (don't like paying labour but run out of things to check)

I have tried a different magneto as got 2 spare bottom ends and still done same thing so don't waste your money just yet as I still think its some thing simple

Hey glad to see I'm not te only one with this problem

And I've read that post about ten times now don't really help me to much thanks tho

It might be going to a shop tomoro if I can get a deal on some cheaper labour if it does ill post what the problem was if they find it (don't like paying labour but run out of things to check)

I have tried a different magneto as got 2 spare bottom ends and still done same thing so don't waste your money just yet as I still think its some thing simple

Thanks on the heads up...

Looks like I won't order the stator yet.

No worrys if you get any luck let me know please same as I will let you know