[DT125R Major help needed .....please]

Hi Mark,

just so I get this correct .... you connected the valve up when it was fully open and you lost performance from doing that ? A simple way oh checking that the valve is in the correct position is to remove the exhaust pipe so you can look up the exhaust port and switch the ignition on and after the servo cycles the valve should end up closed if you are ending up with the valve open you have the thing connected up incorrectly in one of 2 ways

1) The cable pully was connected to the valve in the wrong position

2) The cables are fitted the wrong way round

With a bit of experimentation you will end up with the valve in the correct place.

Your coolant leak :- Has the engine/cylinder have and white streaks on it ? If so these will give you a clue where the leak is but if not I does stand a chance that you do have some coolant being expled from the overflow. I guess you filled the rad and squeezed the rubber pipes in order to expel the air ... if not you may have an air lock which in turn will cause coolant to dribble from the overflow

Regards Jim.

Hi Jim

I must have put the valve in the wrong way round as the pully was conected in the right position and the cables were fitted right ...........i didnt look when i put it in i know my bad ! but i turned it 180 this morning and its now fine

ooooooooooooooh i didnt squeeze the rubber pipes shall i just drain it again and refil it properly or will it just sort its self out?

Regards

Mark

[DT125R Major help needed .....please]

Hi Jim

Im going to have a look tomorow i should have taken a note of how it was before i removed it

How do i know when i have it in the right place how would it look inside if i looked through the exhaust port when its in the right place? would it be fully open .....im getting confused

What do you think about the air filter cover ?

Regards

Mark

Well ive turned it 180 and it seems to be how it was now

One last thing i now have a coolant leak from the underneath frame next to foot peg on the last hand side i did drain and refil the system .........would this be just an overflow pipe>

Thanks again

Mark

[DT125R Major help needed .....please]

Hi Mark,

it sounds like you have hitched up the valve incorrectly ... did you leave the l/h cover off & cycle the valve in order to work out that the valve is in the correct place ? There is a chance you have the valve 180 degrees out which will shut down the bikes performance and it will be a simple point of turning the valve around the correct way before the electrics are connected.

Regards Jim

Hi Jim

Im going to have a look tomorow i should have taken a note of how it was before i removed it

How do i know when i have it in the right place how would it look inside if i looked through the exhaust port when its in the right place? would it be fully open .....im getting confused

What do you think about the air filter cover ?

Regards

Mark

[DT125R Major help needed .....please]

Hi Mark,

Power Valve engine so you did answer that its got the kit on now (that is not standard for a UK bike) and if the bike is a UK it is possible that someone fitted the servo kit badly (simply crimped the sealing rings). But by now I would guess you have the cylinder off the bike and the problem solved.

Regards Jim

Hi Jim

Well i have changed the o rings and seal and there is no leaking oil up to now so fingers crossed

Now another problem i guess i must have put the power valve back in wrong

I no longer have the arm pulling acceleration i had before and it now struggles to hit 70 ...........what have i done wrong ??

Also the previous owner had lifted the air filter covers to alow more air in ........is that normal

Thanks for all your help

Regards Mark

[DT125R Major help needed .....please]

I thought i used red, must have been invisible.

Hi

please accept my apologies for not replying to your comments

I did appreciate your help and i was going to let you know about the power valve moving once i had taken it out and checked it

Once again forgive me if you think i was been rude but that wasn't my intention

Regards

Mark

[DT125R Major help needed .....please]

Hi Mark,

35mpg is not too bad for a PV engine running at the max (without the servo motor connected). To ensure it is working you will need to hear the cleaning cycle at startup/igniton on and just back off the right wrist. I would guess you dont have a full valve motor as if the bike was leaking it would only leak from the right as the servo/cables etc are situate to the left & it would be a bike in a sorry state if the valve was was leaking here.

Regards Jim

Hi Jim

Im afraid it is leaking from both sides but only a small amount from the side with the servo and yes i can hear it turning both ways when i turn on the ignition

I am going to remove the cylinder head tommorow and have a good look at the power valve and check the piston rings at the same time

Ps whats a PV engine

Regards

Mark

[DT125R Major help needed .....please]

Hi Mark,

is the valve connected up or just pegged open ?

with exhaust gas & oil comming from the power valve cases it may be worth a check on the exhaust port for carbon build up

What MPG ru getting

Regards Jim

Hi Jim

I believe the valve is connected i am going to replace the orings and seal tomorow and i will check the exhaust while im at it

The MPG is a very sad 35 ???

Thanks Mark

[DT125R Major help needed .....please]

Hi

Ive bought a 10 year old DT125r and ive had nothing but problems and i was hoping to get some help on here?

The previous owner has had it derestricted it had dep exhaust and thats about all i know of the bikes history it has 15000 miles on the clock.

1. i have blach gunk and blue smoke coming from the power valve caps on both sides (ive ordered now seals and o rings for this)

2. Its using a lot of fuel

3.The spark plug indicates over rich fuel/air mixture but the haynes manual doesnt tell me how to fix it

4. the bike is running very poor at low revs and speed i have to change gears very quick as it sputters it feels and sounds like it misfires when im around town but as soon as i go on an open road and about 6k the powerbank kicks in and it nearly pulls my arms out of the sockets and only then does it run fine

If anyone could give me some advise and somethings to try it would really help me out

Kind regards

Mark