DT125R FORUM

Yes i will be back with another one for sure in a little time, cheers.

Well Calum first thanks for your help while I rebuilt my 7000 mile 2002 DT 125 R.
But sadly I am moving island and have had to sell the bike,I think i went through every emotion owning this bike as I was sold a lemon and had to do a lot of work to get her running perfect but after running her in i fell in Love with her and there is just something about a 2 stroke engine that is fantastic had a lot of yamaha's starting with a FS1E DX fizzy Reg UFW 274R (still on the road with someone) to RD 250E to a RD350LC, the person who has bought her loves bikes so she is in good hands, Bye for now and again Thanks.

75 mph on 2002 DT 125 R reed switch out of clock, have to say have been a lot faster on other bikes, but 75 mph felt like 140 mph lol, that front end gets light, my Uncle once had a go in a Audi Quattro as a passenger with a top rally driver. At the end the rally driver said well sir you at least know what Adrenalin is now its Brown and runs down your Leg LOL,I know how he felt now lol.

@tdrpaul I remember those days to of people saying that Jap Crap, but they got there act together and the rest is history,it will happen with China to.

point taken Calum, but speed limit on island is 25 mph ( which everyone seems to ignore lol ) but the roads are twisty ,potholed have gravel on corners sometimes and are up hill or down hill never straight so riding bike hard is not easy here and do not get me started on local driving skills like stopping to chat with someone on a blind corner, but totally agree that its not a 4 stroke so needs to rev a lot more now its run in, Cheers.

Well before doing power valve I thought I would take bike to the only straight piece of road on island 0.6 miles long (yes you read it right).
So really revved in every gear to about 8500 rpm until changing gear and got bike up to 70 mph in 0,4 of a mile before having to hit brakes before road runs out at 0.6 of a mile ,so I was just not revving bike hard enough when I tried first time because still had my treat it gentle running in head on.
There is no where on island to go any faster than that so I;m not going even gut the exhaust as what is the point . So going to leave bike as it is ,thanks for help.

Ok will pin power valve and try it then get back to you,cheers

This is one of those questions which gets asked a lot,but having read a thousand links (maybe not quite a thousand lol) I am still not 100% sure so where better to ask than the home of the DT 125 forum.
So a little history of bike top end has been overhauled re-bore piston rings etc,Carburetor has a 240 jet in it, new airfilter and reed switch out of way bagged up and taped up, Exhaust is stock and not gutted but has a KMX 125 tail pipe fitted ( that;s how it came to me) . bike accelerates decently through gears and revs well upto 7000rpm in most gears but once it reaches 60 mph it just stays there 55 mph up hill. Is it the CDI or have I missed something.

@Calum Oh yes fitted one , cheers

Well bike is running perfect now , found problem to be a very small partial blockage in idle Jet so all good now busy putting some miles on the clock running bike in, thanks for help and inputs Calum.

@Calum Well got bike started and got it home but tick over is to high starts at 1500 rpm then quickly rises to 2500 rpm so bike is not running on idle Jet so investigation needed there,but the original fault of bike stopping I think may be a intermittent electrical problem so going to check all earths and wiring loom,
I am always happy to get advice from knowledgeable people like your good self, because I might have been at it a long time but you never no it all unless you are a no it all LOL..

Well Calum LOL Ive been an MEP Engineeer for 35 years and trust me not all faults are equal but get your point,
Weird thing is did a spark test and there was power,So tried bike and it started but would not idle so even though there is a petrol filter fitted I have stripped carb to clean just in process of rebuilding so will see how it goes, cheers

yes there is power to rest of bike,going to bike now to start tracing from power source battery onward hopefully will find fault, not a big fan of electrical;l faults ,more into mechanical faults.

Yes took spark plug out and tested against frame, have already bypassed side stand switch will have a proper look today

Well bike was running perfectly finally so took it out for a spin and after 2 miles it started to slow down until it came to a stop halfway up a steep hill brilliant.
So noticed choke was on so thought that was the problem so cleaned plug,I carry tools as this bike is not reliable, and still it would not start, ran it down hill and tried to bump start still not staring,, bike smelt flooded so took out plug cleaned and dried, checked fuse OK checked kill switch position OK,but no spark at plug when tested, it is a brand new NGK, any clues anyone

@Calum Hi Calum
Bike running perfect, thanks for help, posted what I did so Post is complete, my pet hate on another forum was old posts that were void of the fix or work done. Thanks again.

Set clutch up took 5 minutes and yes the bike is running like a good un no clutch slip ,and no smoke trail any more correct Jet maybe or carb was not set right anyway all is good ,and feeling the love once more, now just another 450 miles and it is run in .Thanks for help.

240 jet fitted and running just as well ,ticking over nicely got a jet change down to 20 minutes thanks to plug on bottom of bowl ,could not face another re-bore as 5000 miles from mechanic lol, now just clutch to adjust, cheers for help so far.

Well thats good news about the WD and clutch, after rebuild Clutch was way out and took a lot of adjustment ,will check tutorial link and also have a haynes so maybe he says with fingers crossed it might just need adjusting. But with cars i have found once there slipping you have to change them ,is it the same with the DT.

@Calum Just remembered when engine seized I sprayed some WD (moment of madness) in Barrel so Transmission oil probably contaminated which in turn probably contaminated clutch plates so even though I've changed the oil it is still on the plates themselves .
will fit the 240 jet in morning and see how it runs, this bike is like a show jumping horse always another fence to clear it is now the most worked on Bike I have ever owned not feeling the love at this moment lol.