DT125R ARCHIVE

syks · DTR Respected Member

RE: Power Valve Exact Guide and Position ??

polsta · DTR Senior Member

nice one mate sounds good !

read the end of page 1 on this thread, you must of just missed it !! its now an animal !!!

let me know when your on the road then,il see about riding up to andover and what way id have to go etc, as ive never been there !

im just gonna see about getting abigger main jet now, gonna search net n ring local places

syks · DTR Respected Member

Nice one mate,youve finally got her sorted,i think you will probably need a 260 main jet and its prob best to just ring your local bike dealers/yamaha dealer to get the main jet,i might be on the road tomorrow mate if i can raise the cash for the cbt and insurance etc.

polsta · DTR Senior Member

nice one mate, good luck with it !!

im with a quote insurance fully comp , with nowich union , £160 with breakdown cover !! paid £30 odd up front then £15 a month or sommin silly !!

,just rang round local shops, 1 place is shut today but spoke to him on mobile and hes got them in, and another place said they got a few but is mine hexagon or a screw one, do you know ????? , and best to pop in with my haynes manual and theyl see

i think its 210 in here, would 260 not be a bit much and i need a 240 ??? , would there be much power /fuel consumpsion difference between the 2 ??

she f**kin flys now tho,i cant wait to go out for another ride in a bit ,i might ride up there this arvo then i can get my mate to help me do the jet tonight , woder what shel do with that in ?? lol

-- Edited by polsta at 13:11, 2008-08-11

syks · DTR Respected Member

I thought the same mate,(that it had a 210 as standered) but everyone on the yamaha site recons it has a 240 as standered? if it is a 210 then a 240 will be fine but if its a 240 standered then a 260 it would have to be and yes i think it is a hexaganol jet and yes the fuel consumption will be more,you will get less miles out of ya tank.Ive raised the cash mate thanks to me dear old man lol so im gona try n book my cbt for tomorrow,a quote was the cheepest ive found to mate and will be going with them but only third party fire and theft,cant wait to be FINALY legal.

polsta · DTR Senior Member

sweet mate, shud fly through your cbt, how much is that costing ya ? think mine was 60-70 odd

just put all the bike back together all proper and put everything away, shes good to go apart from the main jet now ,il give it a week or so like this to really get used to it, then il try it with the servo on and see how i find that !!

whats your bike set up mate ? year/exhaust/power valve/ jet size, and speed ?

the haynes manual says its a 210 jet, but spose i wont know till i take it out ? does it say on it what size it is ?

or doesnt acttualy matter and will give more power anyway to just put a 260 on weather its a 210 or a 240 ?

cheers mate

-- Edited by polsta at 14:43, 2008-08-11

syks · DTR Respected Member

Got my cbt booked for saturday(was the earlyest i could get it) Ive got a 94 dtr,not sure if the valve has been done but ive got a full dep system on it,ive got a small hole in the front pipe though so might have to put the standered exhaust back on her,it does 80mph and is FAST getting there,theres a vid on here(i think in this section)of me bike with the exhaust on it,its called DEP EXHAUST SOUND

polsta · DTR Senior Member

nice one mate il check it out, il make a vid of mine when ive sorted the jet

also got a brand new blue seat cover i need to do, to change mine from black (the bikes blue)

you need to sort that hole, cant ya patch it up somewhow ?

what size jet are you running ?

i reckon once that jets done and it revs to the max rather than spluttering at 10.5 il do 80 surely ? its gotta add at least 5mph youd think ?

syks · DTR Respected Member

I havnt touched the jet myself but my bike redlines in every gear and runs out of petrol quick so one of the previous owners may of done it already(theres been 12 previous owners of me bike lol) it should defo make it faster as it is letting more petrol through to the engine.

polsta · DTR Senior Member

ok mate nice one

im all showered n just off out for a nice ride n some fun !!

hopefully i can get a jet tomorrow in the morning and get it in tomorrow too, i cant wait !

Gixergav · DTR Senior Member

Glad i could be of service! Try a NEW plug to cure the spluttering first.Cheap and easy.If that doesn't solve it then yeah fine, try upjetting to a 260 main jet.I have never needed to upjet a dtr though personally.Whats your mixture screw set at? It should be at stock setting at 1 1/2 turns out.Make sure the airfilter is clean.Have you been inside the carb? The jet needle should have its clip fourth from top.

polsta · DTR Senior Member

ive tried 2 plugs and both same, 1 (that ive left in at mo) is a new irridum one

the spluttering now is not major and none at all if you dont rev past 10 ,i know you shouldnt rag it anyway all the time, but it just needs addressing to get it at its best

ive never touched anything on the carb, never touched the screws or anything ?

spoke to my mate earlier, he said if i get the jet tomorrow hel help do it,and show me how to take the carb off and clean it etc, said we can clean the floats out and stuff

i presume the carb is at stock , but i cant be sure !

do you think it might just need fine tuning then rather than a new jet ? would the new jet be good to do anyway to get more fuel/power ?

any idea what %%% more fuel it will use ?

, so the mixture screw 1 1/2 turns out...what does that mean excatly ? can you give me an exact guide how to check it how it is now and how to get it to how you say ? as i dont want to balls it up

is there only 1 ajustment screw on the carb that can be fiddled with ?

thanks mate , top man !!

Gixergav · DTR Senior Member

At the side of the tickover adjuster screw you will see a brass straight headed screw recessed in a hole at an angle.Use an exact fitting screwdriver and turn the screw in until it stops.DO NOT FORCE IT ANYMORE THAN THIS.Then turn the screw back out 1 1/2turns.The jet needle is on the throttle slide.Undo the two screws at the top of the carb where the cable goes and pull out the throttle slide.You will see a long thin needle.Use your manual cos all the infos there.Make sure the clip at the top of the needle is fourth from top.If that doesn't clear the splutter then upjet to a 260.It wont make a great difference on fuel.

polsta · DTR Senior Member

right ive just had a quick look , and see the screw in the hole !

what is the tickover ajuster screw ? is that the bigger cross head brass screw ? can i ajust that then when the bike is ticking over to ajust how fast it ticks over ??? what is best for that to get it just right ?

is that the only 2 things you can ajust on the carb while its on the bike still without removing anything ?

,il give the mixture screw a go in a min and test ride , il take a little screw driver with me, so can it be ajusted while im on the road ?

do i just need it 1.5 turns out ? if i find it is already and still splutters, can it be ajusted more to see if that fixes the splutter ?

Gixergav · DTR Senior Member

The tickover screw does alter the tick over speed.Around 1200rpm should be fine.Turn it in to increase the revs.Set the mixture at 1 1/2 turns only.If you turn it out too far it will run lean and a lean two stroke becomes a seized two stroke.

polsta · DTR Senior Member

ok mate nice one, im just going to see now and have a go

il be back soon...

polsta · DTR Senior Member

right just got back in, it was more than 1.5 turns out ,more like 2.5 i think

but set it to 1.5 and its still a bit spluttery around 10k in , in gears 2/3 sometimes its about 9 , later hears its later

so does that mean i need bigger jet to let more fuel in ?

im a big lad at about 6`3 and 8 stone, so maybe with my weight on it it needs more fuel gettign through at them speeds and revs ?

Gixergav · DTR Senior Member

Try a 260 jet and check the clip position on the jet needle

syks · DTR Respected Member

polsta wrote:

right just got back in, it was more than 1.5 turns out ,more like 2.5 i think

but set it to 1.5 and its still a bit spluttery around 10k in , in gears 2/3 sometimes its about 9 , later hears its later

so does that mean i need bigger jet to let more fuel in ?

im a big lad at about 6`3 and 8 stone, so maybe with my weight on it it needs more fuel gettign through at them speeds and revs ?

8 stone mate,that bike should fly with you on it lol im more like 14 and a half stone lol but im only 5`10

polsta · DTR Senior Member

LOL , 18 stone sorry not 8 !! im a big lad, it goes 75 now and gets there fast, it gets to 50-60 lighting fast...so for it to shift me that quick its got the power

Gixergav wrote:

Try a 260 jet and check the clip position on the jet needle

...gonna get one tomorrow mate and get it in, also gonna give the carb a clean too

cant wait to get it sorted , il be happy then !! then just be able to concentrate on cosmetic stuff then as shel be an animal, im lovin how she is now smile

-- Edited by polsta at 00:18, 2008-08-12

syks · DTR Respected Member

Mate when you get it sorted you will be well chuffed but theres no need to red line it all the time,even though mine will redline i usually dont take it past 9/10k and its still fast as fook,i dont think it will be healthy on the engine to give it too much stick all the time

polsta · DTR Senior Member

yeah i know mate ,i never really red line it , just the odd occasion when you want that power right to the end of the gear !

i just want this spluttering sorted so i know its sorted and all running fine and can red line if i wish and the bike will go maximum speed then, as in the early gears it splutters slightly earlier !

im just off to get the new jet after breakfast and should have it fitted in by this arvo and she should be tasty !!

in just noticed in the manual, 99 onwards dtr`s have a 240 jet , pre have a 210

so where mines a 98, it might only have the 210 , so i might by a 240 and a 260 if they are only a few quid each and they have both , so when i take the carb off if it only has a 210 il put the 240 in or if it has got a 240 put a 260

syks · DTR Respected Member

jets are only a couple of quid mate,didnt know that about the year of bike and the jet sizes,think someone might of done my jet already cause i get no splutter and my bike dont overheat.

polsta · DTR Senior Member

i had a 240 in , cost me £3 for the 260, its all in now and im good to go , was all straight forward apart from being hampred by frequent showers, carb was all brand new clean looking inside and out and didnt have any problems and learnt more about the bike today !

just waiting for the water/anti freeze mixture to cool down so i can fill up the coolant tanks , then im good to go

only troble is its pissing down with rain at the moment so might not be able to have a proper test ride for a bit

(((((((((((((

polsta · DTR Senior Member

finaly stopped pissing down and dried up a bit, been out for a ride and theres no spluttering now and its running real nice

only thing now, it wont rev past 9.5/10 , weather in gear or neutral so must be a restiction not letting it

so that leaves me to think the only thing it can now be is the exhaust, and is the inner restrictor bit in the front pipe hasnt been removed ?

surely it cant be anything else ????

Gixergav · DTR Senior Member

Sounds like the 260 jet is slightly too big and flooding the cylinder at max revs.Try the 240 but raise the jet needle by one clip position.And 10k is really all you want to be revving to on a dtr.Anymore is asking for trouble

syks · DTR Respected Member

Mate i would try the big one exhaust on it again to see if it will rev past 10k with that on it before you change the jet again as the standered could still be restricted.

polsta · DTR Senior Member

i dont think the 260 is too big gav ? , its more or less the same as it was with the 240 just a touch smoother, and when i held the 2 jets up next to eachother to the light they looked exactly the same

when i had the standard front pipe on originaly it wouldnt rev past 8k anyway, which is why i bought the big one then it reved all the way

the bikes rides lush how it is, but in 2nd n 3rd sometimes it has the burb arund 8k, slightly more in the higher gears, and you cant get a 100% smooth ride, if you rev that tiny bit in to that area it does it....so i need to get it sorted

but when you rev it in neutral, you can see it hit around 9, then like get kicked back/burbs a touch and wont let it rev right up

my mate whos had a lot of bikes over the years was with me he said..you can see its got something in the exhaust not letting it rev right up

thats all i have to sort to get that final bit of power and il be 100% happy with the bike

sorted the coolant and gave the air filter a proper clean and just re-oiled it and put it back in

, spoke to my mate whos got a grinder and a welder, were gonna do the exhaust tomorrow night

anyone here ever de-restricted a front pipe before ??? and got any hints/advice about cutting it then re welding it ? , as ive never seen or done it and neither has my mate !

also....gav, what is the jet needle ? i completly forgot about that and didnt check what one it was on, im not sure what it is im looking for ?????

nice one !

Gixergav · DTR Senior Member

A 240 and 260 jet will look identical,there is only the tiniest difference but it has an effect.The jet needle is attached to the slider in the carb.Remove the two screws at the top of carb where the cable goes.Pull out the slider and you will see the needle.Use your manual cos its all in there.The clip on the needle should be on the 4th groove from top.If it isn't then put it there.Thats the stock setting.If its on the 4th groove then raise it by one groove and try that.If your bikes powerbanding as you describe then i doubt the pipe is still restricted.It may be worth cutting it open to check anyway.Cut the weld that joins the expansion chamber to the bottom half.A kinda ring of weld that runs round the fattest part.If its restricted then thats good news and set to getting the restrictor out.

polsta · DTR Senior Member

ok mate il check that all out !

i know the manifold restrictor has been taken out, as you can see !! but im not sure about the inside one, with how it was before where it wouldnt rev past 8k, and then all i did was put the big one pipe on and nothing else at all...then it reved all the way , would that indicate there is a restrictor still in the standard one ???

, so the bit i have to ajust, i did look in the manual but couldnt see that bit, so its the needle on the 2 screws bit ?? , ie i dont have to take the carb off again , i canm just undo that top bit ? ,what clip is it exactly ??? i dont quite get where you mean ? im looking at the manual now but cant see the clip bit or what you mean ?