Had alot of problems with power on dt125r 2003 tried everything to sort it jetting, so called derestrictions but no joy. Then desided to change my dep exhaust as had snaped of b4 i got it n repaird with 40mil stainless bends now i have put arrow on runs ten times better pulls bottom end n screams top end like it should but between 6000 and 9000 its just dead bogs out sounds realy deep with no pull any ideas on what this could be finking air to fuel ratio myself but is it too mich air or too much fuel im on 230 jet. Would be grateful for any expert advice lol as 1st 2stroke n dont really have a clue
Ive had my fingers up n set the pully with the valve flush with the top of exhaust manifold, how do you go about pegging it open just to see if it is the servo?
Snorkles off n am on 230 main thats standard i think for flatslide not sure tho?! The floats are slightly bent straightened them the best i could. Ill try pegging it 2nyt see how that goes
The carb isnt something you can take a "best i could" approach with, unfortunatly. The jetting and carb condition is vital to a 2 strokes running well. Your bent floats could be causing a problem. Sounds like the powervalve was operating fine so can rule that out. I'd do a full check on the carb and replace the floats if they are damaged.
Am pretty sure the problems carb based. Wouldent start this murn either think its flooding got a 210 main jet to put in and will order new floats and post outcome thanks for advice
Ordered a second hand carb and inlet manifold should be here mid next week hopefully that should sort it although its of a dtre 2004 i think will that be ok??
Best method for checking the float height i found was bending the drain hose up alongside the float bowl and opening the drain screw. Fuel in the pipe should sit level with the bowl gasket face.
Yeah, unfortuantly so. Alot of people have mixed results with this. I personally wouldnt do it and cant see gaining anything from it but I have seen alot of people do extensive work like this to mod their inlet. I had one come off my DTR 1998 that looked even worse like this. It's gone in the bin now so have no photos but yeah, it happens.
In my mind it alters with the air flow in a negative way. I do know however that on the 350 ypvs, the original manifolds need to have the "stuffer ears" cut away and the inside carefully modified to fit VFORCE REED BLOCKS which are a performance upgrade. This could be where it has come from?
Standards much better it runs sweet now ive put standard in before it was horrid was really load and throaty revved really slowly n jus slow in general. Actually a joy to ride now :)
Why do people butcher the standard parts like that????? Surely it's obvious that Yamaha know far more about building bikes than any of us do ?? If it's any help to anyone on here my DT was standard when I got it. I've gutted the front pipe, put on a DEP tail pipe (with wadding) and put a servo on the powervalve, that's it, everything else is standard. Initially I had problems with the servo - cables connected wrong - but now it's working properly. The engine pulls well from low revs and tops out at 9 and a half to 10 with no flat spots. I use it for green laning mostly so this set up suits me.
