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Ogri

xvs 125 you can get a bit more poke

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I was talking to one of the local mech heads form "grease monkeys" and he told me that there might be some kind of restrictor in the fuel lines causing a distinct lack of power during acceloration on my dragstar 125. I replaced all fuel lines and no difference. THEN I found a small plastic valve thingie in the tank breather pipe. It restricts the air flow to the tank. If the fuel cannot be replaced by air then you get a vacuum in the tank and this enevetably restricts the amount of fuel to the carb. Your air / gas mixture goes out of the window and hey presto massive flat spot. Great when your trying to over take something.

So follow the breather hose from your tank, behind the plastic cover and you should find it there. I would suggest you replace it with an ordinary gas filter ( no valve ) besides it's one way of connecting the two bits of hose.

You should find better response in your lower gears and expect a 10mph on your top end. But don't forget this bike has no bollocks it was built to look good. Still I'm looking for other ways of giving it a bit more top end.

Will keep you all posted. OGRi

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Cool m8 just got myself a 125 Dragstar and heard that there was some sort of restriction. So thanks for that

Just one think after you remove the plastic thing is there anything else required to make sure it ticks over or runs smoothly??

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Cool m8 just got myself a 125 Dragstar and heard that there was some sort of restriction. So thanks for that

Just one think after you remove the plastic thing is there anything else required to make sure it ticks over or runs smoothly??

No mate, no reseting the the needle or anything. If you find that your engine is ticking over a touch faster, you can slow it down with the big plastic screw on the left hand side of the carb.

Glad to be of help. OGRi

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No mate, no reseting the the needle or anything. If you find that your engine is ticking over a touch faster, you can slow it down with the big plastic screw on the left hand side of the carb.

Glad to be of help. OGRi

Job done it works and you were right had to turn the ide down a tad, I got an extra 12 mph lol on the top end :lol:

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Job done it works and you were right had to turn the ide down a tad, I got an extra 12 mph lol on the top end :lol:

Now all you have to do is get rid of the scooters. OGRi :D

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Now all you have to do is get rid of the scooters. OGRi :D

LOL m8, maybe some day when im skint or fancy a bigger bike, I like to think they are Harleys as they often break down as much as them :rolleyes:. :blink:

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Ogri - you are legend. Small plastic thingy removed today - I just bought a new length of pipe but same difference. I'll have to let you know if it changes things as, amongst many other things, the fuel tank leaks so is currently drying out before being fixed in some way. Ummm, any suggestions? I figure welding may be a bit dicey on a used tank :P

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I was talking to one of the local mech heads form "grease monkeys" and he told me that there might be some kind of restrictor in the fuel lines causing a distinct lack of power during acceloration on my dragstar 125. I replaced all fuel lines and no difference. THEN I found a small plastic valve thingie in the tank breather pipe. It restricts the air flow to the tank. If the fuel cannot be replaced by air then you get a vacuum in the tank and this enevetably restricts the amount of fuel to the carb. Your air / gas mixture goes out of the window and hey presto massive flat spot. Great when your trying to over take something.

So follow the breather hose from your tank, behind the plastic cover and you should find it there. I would suggest you replace it with an ordinary gas filter ( no valve ) besides it's one way of connecting the two bits of hose.

You should find better response in your lower gears and expect a 10mph on your top end. But don't forget this bike has no bollocks it was built to look good. Still I'm looking for other ways of giving it a bit more top end.

Will keep you all posted. OGRi

having just read the above i notice you say you found a small plastic thingie as you call it? could this be the non return valve fitted on most breather pipes as a saftey function on most motorcycles?The main points about fuel tanks are these: they need a way of letting fuel out to the carbs, and they need a way to let air in as the fuel goes out, to avoid a vacuum buildup in the tank. We will call this "venting" or "breathing."

And finally, there are safety considerations, mainly involving the situation where the bike falls over on its side. The concern is that we don't want fuel spilling out all over the place when this happens, so we need to block the fuel path and the venting path, so that the fuel stays in the tank in a "down" situation, this is one of the functions of a non return valve

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having just read the above i notice you say you found a small plastic thingie as you call it? could this be the non return valve fitted on most breather pipes as a saftey function on most motorcycles?

You mean the one that allows air to escape from the tank, for example due to thermal expansion of the air in the tank, that if removed could pose a serious threat to ones health and safety? :o;)

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You mean the one that allows air to escape from the tank, for example due to thermal expansion of the air in the tank, that if removed could pose a serious threat to ones health and safety? :o;)

thats the one lisa, bonfire nights only a couple of months off lol

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thats the one lisa, bonfire nights only a couple of months off lol

I thought so.....

Toasted marshmallows anyone...... :huh::lol:

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Excellent I like a good bonfire, at least I will go out in a ball of fire. If your going to go do it in style :mellow:

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Excellent I like a good bonfire, at least I will go out in a ball of fire. If your going to go do it in style :mellow:

Hi, I'm back girls. Just spent a couple of weeks in Crete where there were loads of kids having fun on any bike they could afford to hire. They didn't have a clue about which side to overtake on or if they should be wearing a helmet or not, or if they were a fire ball hazard or not and further more they didn't give a shit! Sorry but that's rock and roll as far as I'm concerned. Bikes especialy little ones are for a bit of fun. Who cares if there is a tiny fraction of a chance that the bike may fall over ( your not supposed to fall off the bloody thing anyway!) on a little Draggy if you are tryin to overtake and the faffy plastic valve restricts your flow then you're knackered anyway! If you start out of a "T" junction with almost no acceleration and MR BMW comes flyin round the corner then your equally goosed! Anyway the damned thing causes a vacumn in your tank and if you thought about it properly it reduces the air intake and was not designed to stop juice comming out. So don't start being a smarty pants untill you have thought about it first. The valve works the opposit way round.

Enjoy bonfire night, but if your scared of setting your bikey on fire leave it in the garage. OGRi

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Hi, I'm back girls. Just spent a couple of weeks in Crete where there were loads of kids having fun on any bike they could afford to hire. They didn't have a clue about which side to overtake on or if they should be wearing a helmet or not, or if they were a fire ball hazard or not and further more they didn't give a shit! Sorry but that's rock and roll as far as I'm concerned. Bikes especialy little ones are for a bit of fun. Who cares if there is a tiny fraction of a chance that the bike may fall over ( your not supposed to fall off the bloody thing anyway!) on a little Draggy if you are tryin to overtake and the faffy plastic valve restricts your flow then you're knackered anyway! If you start out of a "T" junction with almost no acceleration and MR BMW comes flyin round the corner then your equally goosed! Anyway the damned thing causes a vacumn in your tank and if you thought about it properly it reduces the air intake and was not designed to stop juice comming out. So don't start being a smarty pants untill you have thought about it first. The valve works the opposit way round.

Enjoy bonfire night, but if your scared of setting your bikey on fire leave it in the garage. OGRi

Thing that gets me is...What on earth is the great 'OGRI' doing faffing about with trying to get more power from a gutless 125 cruiser wannabe?...Should be on a supercharged Triton or summat, or have he should leave this to the hapless Malc, and sneer from the sidelines as he does his 'Great balls of fire' act.

OGRI why dont you leave the fuel cap loose to prove whether fiddling with this plastic widget is really going to improve things, personally i doubt it but i'll give you one thing..If you remove it the bike will be lighter so that should improve accelleration somewhat. <_<

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Hi, I'm back girls. Just spent a couple of weeks in Crete where there were loads of kids having fun on any bike they could afford to hire. They didn't have a clue about which side to overtake on or if they should be wearing a helmet or not, or if they were a fire ball hazard or not and further more they didn't give a shit! Sorry but that's rock and roll as far as I'm concerned. Bikes especialy little ones are for a bit of fun. Who cares if there is a tiny fraction of a chance that the bike may fall over ( your not supposed to fall off the bloody thing anyway!) on a little Draggy if you are tryin to overtake and the faffy plastic valve restricts your flow then you're knackered anyway! If you start out of a "T" junction with almost no acceleration and MR BMW comes flyin round the corner then your equally goosed! Anyway the damned thing causes a vacumn in your tank and if you thought about it properly it reduces the air intake and was not designed to stop juice comming out. So don't start being a smarty pants untill you have thought about it first. The valve works the opposit way round.

Enjoy bonfire night, but if your scared of setting your bikey on fire leave it in the garage. OGRi

well ogri where do i begin well first let me thank you for calling me smarty pants!i am guilty as charged if by smarty pants you mean that with 45yrs of riding and repairing bikes i unlike your self know what the parts of a bike are called and how they work unlike yourself who refers to things as that plastic thingie,firstly what makes you think that yamaha have put something on the bike to restrict its power it was built for its looks it is a 125cc twin trying to pull a lot of weight, on a power to weight ratio they have no need to put any form of restricter on it the weight if the bike compared to the size of engine is restrictive enough, i dont need to think about the valve and how it works because i have 40 yrs experience building and riding bikes and am still learning, i also have the same bike as you its not my only bike it is my day to day bike for economic reasons not as oldgitonabike suggests because we are harley wannabees if i wanted a unreliable over priced bike then i might get a harley but no i will stick with yamaha and when i want to go faster i will get my other bike out

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Guys i wouldnt even bother. He obviously knows best about what the results of removing the plastic "thingy" is - leave him to it. Someone who thinks that riding without helmets, not having a clue how to ride and performing dangerous manoevres on a bike you know fuck all about in a foreign country is "rock and roll" then you clearly can't know anymore than him - i would save your advice for someone who deserves it and shows a bit more respect.......... :rolleyes:

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Feck me ppl, that just mental riding with no helmet

I bought the bike purely for getting to and fro from work but wanted abit more poke as well. As I am a lazy git I havent bothered sitting my test and the nearest test center bloody 40 miles away, I just sit my CBT test every couple of years. Like most driven on two wheels for 20 years but confess this is my first motor bike of this type. I bought the dragster not because I wannabe Harley cause hate the fecking things but because when you ride the bike it very simliar to driving lambretta scoots you sit in an upright position but just found that these things have no guts and was look for a cheap fix to get a little more guts out of it.

Reading some of the replies and having thought about things the wee platic thingy is going back. Is there any other way of giving the bike more guts without spending a ton of money?????. Oldtimer or Goff seem to be the experts whats your thoughts????

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Seriously badbrad, if you want more performance from a 125 sitting upright...Get a DTR125, It'l eat the little draggy for breakfast IMO

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You could always put a hypercharger on it...........

But Old Git is right - the cruiser 125's are a bit sluggish and will be no where near as fast as the race reps or sit up and begs! My 650 is slooooooooower than a snail in a virgins knickers - im lucky if it tops 110! They aint made to be fast, so if you do want something a little more pokey - what the Old Git says!

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the answer to your question badbrad is twofold with the bike we both have its horses for courses it was never designed for fast acceleration or a top speed like a lot of 125s,its a cruiser comfortable to ride and good looks with the harley fat boy look,yamaha continued with the 650 and 1100 but dropped the 125 although it sold it did not sell in the numbers to enable them to continue to produce the main reason customers gave was slow acceleration and a poor top speed i was told this at a bike show by a yamaha executive so if they couldn,t get any improvement with all there expertise i dont think we will have much luck but if your happy with the looks and comfort enjoy it as its my day to day bike i love it for those reasons,did you get yourself a sissybar? i got one of e bay £107 +£10 delivery highway hawk it said on the box for 1100 dragstar but it does fit the 125 and is good quality it is 7 day delivery but worth the wait, and as oldgit said if you want a bit more speed there are plenty of other 125,s out there capable of a bit more, have fun mate

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