Airhead

Try motocarb for your gasket is your tank venting propery? is there a strong flow of fuel to the carb? is there rust in the carb fuel supply spigot / float valve ?

Hi muss and welcome a bit sketchy on the detail there! What do you mean "its getting through a spark plug every 2-3 weeks and keeps breaking down on me " What is happening to the plug, what does it look like when you take it out, have you checked its sparking, have you cleaned it and tried again, have you burned it over a gas hob? is it breaking down because of your percieved spark plug issue?

Now this is something i have no personal experience of, but with the prevailing weather contitions...could it be carb icing? Google it

Well there you go casting seeds of doubt in my pickled brain, so much so that i whipped the exhaust off again and can breathe a sigh of relief, you can see the cutout flush with the top of the port and arcing down around the curve at the sides...Phewwww I just have a nagging feeling this will cost me a headlamp, what narks me is that he got it MOT'd, Still theres plenty of time i suppose until January, will surely pick up an ebay one by then.

mine is also a 4BL### and JYA4BL### so yours is an import too then and will be restricted in the same way as mine, mine is a French bike it has a km/h speedo and i will put money on it that i will have to replace the headlamp...even though it has just been mot'd. i'm just hoping they will mot it next year with a miles / kilometres converter fitted and a few stickers on the face. I will be fitting the 250...assuming of course i find a 240 in there when i check. If its too big no worries i would rather that than too small. As for the reed switch i dont even know if it has one fitted yet with it being an import but i will check it out all in good time

Way better now with the exhaust tube gone and the PV set (hopefully) correctly. Should be better still with the DEP silencer . ...But i'm running in so wont be getting the full benefit. It just rev's more freely which is what i was wanting but keeping less than 6k at the moment.

Where is the carb number, i cant see it? I have been told my bike as a 4BL import would have a 240 jet as standard. I have ordered a 250 on the strength of this, maybe a 260 will be considered too. You have me wondering now on the power valve although it did seem to be running right. look at this picture, If the PV was upside down there would be a bulge in the exhaust port, rather like a 'sleeping policeman' if you know what i mean, and it would have the same effect too no? To slow it down. I wish i had rotated it round though now.

Might go i usually do. anything for a day out, obviously not as fussy as Drewp's O.T. I'm not nearly old enough to get a concessionary pass, i just chose a forum username badly

Here's another, looks like a complete one, i saw this seller had a 175mx barrel for sale so messaged him as to thread, fins, bore size etc £20 buy it now. he messaged back saying it was all good and standard bore but needing re-bore.....and it sold today Bugger.i'm spending too much time on this 125 DT Headlight

Sorted out my PV today. on removal of the pulley and exhaust i found it to be in the restricted position.By sticking a finger in the top of the exhaust port it could be felt that there was a hollow groove between the port and the PV. This is because the PV needs to be turned slightly more and will then be a smooth passage through port to cylinder with the pulley aligned with the 4mm hole in the cylinder. There are two possible positions to mount the pulley onto the PV, hopefully the pics will make it clearer. Pic 1, Pulley removed and this is the position as found (Restricted) Pic 2. Back of pulley showing how the PV would sit in the restricted position. Pic 3. Back of pulley showing how the PV would sit in the un-restricted position I can report a definite improvement now and the bike is much more willing to rev freely. Cant give it beans yet as due to still running in so revs not going much over 6k at the moment. DEP silencer is on order and a 250 main jet. I believe standard is 240.

Pretty sure they are the same as XT's XT500 Headlamp

Could it be a faulty keyswitch, or a loose connection to the keyswitch?

Welcome back to biking steve, YBR is a good bike in my opinion too but i must admit i like the style of 'trail' bikes

Tis indeed but MaD is just replying to pards, who chose not to start his / her own thread

Welcome Dan Try the 'Search' facility I found this ...Paul

Welcome back jo,

Hello 'chalk and cheese' and welcome

Not just his second post but his first post too....AND that ones in MY topic Scott its not the fact that you are directing the OP to another forum but the rude and abrupt way in which you do so, i suggest that if you dont know anything about bikes then stay out of the 'workshop' 'Seiki' wouldnt like that on his forum !!

Try busters, M&P, L&M, Wemoto to name but a few

Ha! that makes my stebel sound puny

Dunno about my power valve (whether its in the right way or not), will check that out later However back to the exhaust 1: Thanks Vez for the spare exhaust, overall its a good one which is unusual as the headers are often shot through neglect with repainting and cleaning. 2: Took said exhaust to a local engineering / welding oufit today and instructed them to chop it in two so i could remove the internal sound absorbing mesh and restrictor rings 3: Arrived back an hour later to find that theres nothing whatsoever in there 4: so i wasted my time and money on that little exercise, and apparently the older DTR's ie 88 - 96 dont have these things inside but do still have the header restrictor Well at least now its in two pieces i can power wash the carbon out of it

Very informative thread Vez, if my old DT wasnt so 'new' i would be tempted to strip it down

Bought me an 'Apico' stand today. lifts the bike off the ground for cleaning, inspecting lubing etc. motocross riders may well be familiar. Down height 12.5", Up height 16.5", lift weight max 120 Kg. Nice piece of kit, will do for both my DT's But would buckle under the bandit Price...£40

Charge battery Set choke to on No throttle (or very little) Try again

No its a number, they stopped doing it years ago for obvious reasons, perhaps your bike came after the change, ask nets she will know. Have you got any owners manual, maybe someone wrote down the number in there,,,,I would thats for sure