@calum said in Time to change wheels and ...:
pipe
you mean that if the material the tube is made of is the right one ? the #3 in the picture.
I put the tube yesterday to check the pump, later I will put the original. I'm going to add oil to the gas tank. 100 ml of oil for 5L gas. ?
with new cilinder and piston ...
I started the bike yesterday after installing the piston
Hello, I don't know if is good idea to write in this thread . Today I was checking the oil pump and I realized that the color of the oil changed: it has a suspicious color )
( I have put a transparent tube to check the oil flow)
I think it's because of oil seal or o'ring
11. O-RING
-- 13. OIL SEAL
WHat do you think ? Thanks in advance
sorry, the DT 125 "R" version is 17,5 pilot jet.
@calum I was researching. I think in english is called " Pilot jet " and Mikuni TM28 pilot jet size is 15.
@calum yes. those are original Mikuni jets. But what size is the ralenti jet ? 25 or 15 or what ?
( https://www.japanbaiku.com/image/cache/data/chicles_tornillos/kys-00b-500x500.jpg ) thx!
@declan ok thanks, I think the same. But in PJME you can find the Genuine Yamaha base gasket and is the same that I have , made of metal ( I think steel )
http://www.pjme.co.uk/acatalog/4FU-11351-00.jpg
@Calum thx , I will pay attention to ring end gaps. And have bought the Athena head gasket and the original yamaha water pump radial shaft seal.
@terry-tz Thanks , will try read it in English ( I'm from Spain) , and find some literature in spanish.
Now I have disassembled the carburetor and I have understood much better how it works and how they connect the holes. this video helped me a lot:
Chicho Lorenzo ( Lorenzo's father MotoGP)
https://www.youtube.com/watch?v=niNn0LZESfg
My questions are. Our Mikuni carb ( TM 28 ) main original jet is 180 ?
in this webpage you can see specs and the main jet is 180 .
-> https://www.japanbaiku.com/mikuni/mikuni-tm/mikuni-tm28
. Now I have seen that I have 240 all this time , without problems. With the Romeu exhaust will try with 250/260. BUT this jet :
https://www.japanbaiku.com/image/cache/data/chicles_tornillos/kys-00b-500x500.jpg <--- ralenti/starter jet ? the original is 15 . will try 17.5
where do you buy jets kit ? www.japanbaiku.com is a little bit expensive.
Thanks in advance !
@Irongamer727 I have asked him about 170cc kit and the answer was " if you do not tune the Athena kit that exhaust must go good " .
Hello friends !
Finnaly I've recived the piston. While they still fix the cylinder, I am reading carburation manuals and cleaning the Mikuni. I'll buy carburetor jet kit from 180 to 250.
I have noticed that the Yamaha piston rings are different while the Wossner ones are the same:
The Small End Bearing is 17mm ( the one that was put ) but the original bearing for Yamaha piston is 19.5 mm, so is very important replace it ?
And I see that the Wossner piston does not have holes that lubricate the gudgeon pin:
( it might be a good idea to do them? although I do not think so ) )
I have a base gasket but the Genuine Base Gasket it is made of metal (aluminium?) , so It is highly recommended put the metal one ?
uf a lot of questions but thank you in advance . :man_biking_tone1:
@calum said in Time to change wheels and ...:
Grab yourself a forged Wiesco piston and a set of chromium rings.
can't find Wiseco ( one ring ?) piston for my model. But in PJME I have find Wossner piston ( 2 rings) , they are good I think, also forged (?)
Do you know if in PJME there Wiseco piston for the DT R ?
waiting answer from this site . http://www.paramimoto.com/pistones/343-wiseco-piston-yamaha-2-tiempos.html#/piston-dt_125_75_76_684m05600
@calum said in Time to change wheels and ...:
Graham Bell's Two Stroke Performance Tuning
Thanks for the tip Calum . also I have dowloaded the Two-Stroke TUNER'S HANDBOOK By Gordon Jennings. Time to read.
( http://www.2strokeengine.net/gordonjennings/twostroketunershandbook.php )
so, for now I'm going to polish a little bit where it is needed , also the power valve , because it is very dirty.
Mitaka pistons are good ? where you can buy original Yamaha DT R parts online ( like water pump complete repair kit) ? <--- have find this official site : http://www.recambios-yamaha.com/es/dt125r/2002/bomba-de-agua.html
Thank you very much everyone, your answers are very useful.
Hello ) !
I will go tomorrow to the workshop with the cylinder for bore. I know is privileged information and long testing time but do you know where I can find information about tuning cylinder transfers, I think is good idea do something there before it will be bored. Maybe in the same workshop they do that for extra €, will ask.
all this marked with color dots can be modified/enlarged : ?
at the top of ALL the transfers: (?)
so, thank you again for the help, and gas gas !
@tdrgreg2 XD "fuckingline" in Spanish . Cheers !
@Calum **thanks to everyone ** . One question ( maybe a little bit stupid) XD . What material the cylinder is made of ? And the cylinder sleeve ? ( Yamaha DT 125R )
The cylinder sleeve Iron?
Cylinder Aluminium ?
Have you tuned Yamaha cylinder ? ( admision / exhaust transfers etc ?)
Cheers !
Yes, the cylinder was rebored at least once. Now I'm looking where do that again. Thx !!
@Calum > ?
@Calum thx again! do you know how to extract the power valve from the cylinder ? ( for cleaning and modify )
@Irongamer727 Ok ! )) Do you need to readjust the oil lubrication after install the Athena kit ?
Thx a lot .
@Calum You mean just adjust the power valve position ? ( cables ) Thx !
Hello ! Now I will try to explain my situation with photos ( sorry for my english )))
first, I had a problem with yamaha dt lip seals ( water pump) ( the motorcycle was stopped more than half a year) , I changed it, but after that , the next day riding my bike the rear wheel suddenly blocked. Now I disarmed the cylinder and you can see whats going on. So I cant imagine why that happens , original cylinder and piston only 10000 km. And it's almost impossible to put it wrong the water pump and seal. ( or not
The Yamaha DT 125R cylinder is sleeved ( iron ? ) can be repaired. or go for Athena )
Can it be the fault of the oil pump ? how to check it¿ ( the engine thermostat works well.)
?
Usualy I buy in Wemoto.com . Thank you in advance !
@declan That's great idea .
That's great ! Maybe you know if the YAMAHA XT125X 2005 Wheels
( Front: 100/80x17 - Rear :130/70x17 )
fits on Yamaha DT 125 R 2003
( Front: 80/90-21 - Rear: 110/80-18 )
? ( I mean hub dimensions )
Thank you very much for the answers. Yes I will see what can I do with my Yamahas cylinder, maybe only buy the Wossner piston and tune some things . But wanna get that ( Enduro) exhaust from ebay.
@Calum your DT looks great , bravo. :clap_tone3:
