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xv 125 non starter help please


fridgedoc
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Hi All

totally new to all of this...born again biker, with a xv 125 non starter, the story so far, bought bike on ebay told "one cylinder low on compression" Tried to start bike, nothing, could not smell petrol, plenty in tank, changed plugs as one was wrong type and checked for spark, spark OK, tried to start again, nothing again, not even a backfire, and no smell of petrol, removed plugs very slight smell but plugs dry, must be fuel problem, removed the necessary and took side off carb had some sh1t in it cleaned out,removed jet, partially blocked, cleaned, blew out all parts with comp/air, reassembled and still nothing, turned over for a good 30 secs with full choke and twisting throttle, held hand over exhaust no smell of petrol, removed necessary for removal of carb, now trying to get carb off but cannot see how it comes off have it half off at the moment (if only I could get hold of a workshop manual, it would get rid of the guess-work) the inlet of the carb was not fitted to the rubber flange either so this may have some bearing, will need to check the air filter.

Well thats enough of me babbleing on, many thanks for listerning, any help gratefully received.

Fridgedoc

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hello there and welcome to the forum, the xv 125 engine are very temperamental you need to make sure that the battery is fine, the sparkplugs are ok and that the carb and air filter are on properly.

you said something about the front cylinder having low compression? open up the cap for putting oil in, if you can smell petrol or get a creamy substance then the piston rings have gone,

after you have checked put a little motor oil (say a tablespoon) in the sparkplug hole on the front cylinder. if it is your piston ring then this should seal it temporarily, then you need to bump start it (with choke off give 10 twists of the throttle then push in 2nd gear down a hill whilst turning the throttle till it catches and starts)

this should at least get it going for now, let it warm up for 10 min then turn it off and it should start with the button, then turn it off and let it cool down for 30 min then try it again with the switch, if it dont start then you know that you need some new piston rings!.

and lets hope that it is just the piston rings! mine decided to blow the bottom end .....again and it always seems to be the front cylinder.

but its a simple job to change the rings (iv had to re-build the whole engine last week)

hope this helps for now keep in touch

.Paul.

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Hi Paul

can't bump start it, it's in bits, carb half off, found a manual for a 250, I'm guessing it's the same bike just bigger engine (can't seem to find a 125 manual)but it does not tell you how to take the carb off, mine is jammed half way out and don't wont to go any further, been working on house this morning, just about to have another look at the bike, tried the oil in the bore already did not seem to make any difference, there does not seem to be any juice going through the carb I'm guessing it needs a good clean hence the reason for getting it off, once I've done that an inspection of the air filter as I think the previous owner was a welk, I have worked on many a bike when I was a lad BSA Bantam,Triumph cub, Matchless 250, ect.and I'm a dab hand at cars just need a little practice on the bike and I should be up to speed ;) as they say!!!

Will have a look at the oil as you said.

Shall keep here checking for any replies

Kind Regards

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you should b able to undo the metal clips top and bottom then just pop it out (it just slides out of the rubber)

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you should b able to undo the metal clips top and bottom then just pop it out (it just slides out of the rubber)

Hi Paul.........undone top and bottom clips removed throttle cable, no idea how the choke cable comes off but would not stop the carb coming out removed wirng and rubber pipes now it will not push up into the top rubber enough to allow the bottom of the carb to come out of the bottom rubber so have taken it out from the top but the top rubber is stopping it from coming out it just needs a cm and it would be out??????

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Paul...............we are winning.............hey I've got a new carb..............no it's not, it's the old one but it looks new now!!!!!!!..........inside and outside.....now all I've got to do is refit it....... I took it out from the right hand side......is this the correct side?

checked oil no white gung could not check for smell of petrol as I had petrol all around me with taking the carb off.

Stopped for supper now (thai seafood curry) will remove top rubber it's really mucky and make sure it fits over top of carb, it was not fitted to top of carb before just touching face to face.

right it's on the table.......speak soon......thanks for you advice and help..

Stephen

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Am I right in thinking that the xv and the xvs use the same engine Paul?

If so, the choke cable will come out like many other cables on the bike - perhaps, if it's too tight, give it some free-play on the handlebar side.

I took apart my xvs125 loads recently - it's DEFINITELY worth checking it out. And I've got exactly the same problem with my engine. When we eventually got it started (by putting oil in spark plug hole) it would max out around 10mph so yeah the compression was f**cked.

I still haven't got round to changing me rings yet. I'm enjoying my new engine as it is :). Perhaps Paul will give me a tutorial sometime! haha.

All I can say is charge the battery, and try starting it with oil in the cylinder. One of those squirty-bottle things is DEFINITELY worthwhile.

Hope this helps.

Chris

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glad you managed to get it out lol do you think it would be worth taking the airbox off to put it back in......itl make it allot easier ;) now the choke cable is either a little bracket with a plunger (like on the dragster chris) or its just a wire going into what looks like a bolt (you undo the bolt all the way then slowly pull it out)

right if you put it all back together then turn the petrol tap on. look on the carb (should be the side where the jets are) there should be a like spout with a screw on the bottom of the carb body, further up should be a line on the carb that shows the float bowl level, attach a clear bit of tube to the spout and hold it up then undo the screw, this will release the petrol from the carb into the pipe and should go up to the line marked on the carb. this is the float leval and it should be bang on.

then if thats ok turn the screw back in (so you dont loose fuel) and then put some oil in the cylinder and bump it, you need to bump it cause the switch wont work if the rings have gone, if you can get it started listen to the engine if you get any loud knocks then turn the engine off and get back to me.

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Am I right in thinking that the xv and the xvs use the same engine Paul?

If so, the choke cable will come out like many other cables on the bike - perhaps, if it's too tight, give it some free-play on the handlebar side.

I took apart my xvs125 loads recently - it's DEFINITELY worth checking it out. And I've got exactly the same problem with my engine. When we eventually got it started (by putting oil in spark plug hole) it would max out around 10mph so yeah the compression was f**cked.

I still haven't got round to changing me rings yet. I'm enjoying my new engine as it is :). Perhaps Paul will give me a tutorial sometime! haha.

All I can say is charge the battery, and try starting it with oil in the cylinder. One of those squirty-bottle things is DEFINITELY worthwhile.

Hope this helps.

Chris

Hi Chris

choke cable out....see above post...have cleaned carb out some of the jets where blocked, not sure whether there is a problem with the rings, the previous owner "was told there was low compression" that was it, I don't think they checked anything else. Apart from the battery being fully charged I linked up a car battery to it as well, to my mind it should have tried to start even if only one cylinder was OK, if it coughed and spluttered but I got "nothing" not one cough, also as posted turned it over for 30 sec choke on and twisted throttle and no smell of petrol I should have flooded the engine and one plug was totally dry and the other smelt a little so no juice getting through is all I determine, I think the previous owner polished it a lot as its nice and clean but spent nothing on servicing it, I will go right through it oil and filter change ect.

Will fit carb tomorrow and take out air filter as I a guessing that will be full of crap, and also get the top rubber secured to the top of the carb which it was not.

thanks for your input chris it all helps.

Stephen

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Hi Paul........thanks for getting back to me.............was I right, the carb comes out on the air box side??

before I try and start it again, I will do as you say regarding float level then I'm going to check and see what the oil is like, I will drop a little out of the drain plug and also check the level, sight glass looks clear so its either clean oil or no oil, its 9.40 here (we are an hour ahead of you) and I've had enough for today, this is what happens when you get old :( ....will give you a shout tomorrow and let you know how I get on.

Thanks again for your time and assistance

Stephen

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Was the problem with mine :P

It's also worth getting some cold-start/easy-start, just so you don't have to stick the tank back on every time to see if it starts :)

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Bike has to upright, not on the stand to check level of oil.

Going back to the apparent lack of fuel earlier, is the fuel cock a vacuum type and if so did you have it switched to the 'PRIME' position?

Hello there........thank you for the info, I guessed it had to upright on a level surface, and yes I did have it on prime, before removing the carb I had the side off and the float chamber had plenty of fuel in it.

Thank you for your input

regards

Stephen

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Hello there........thank you for the info, I guessed it had to upright on a level surface, and yes I did have it on prime, before removing the carb I had the side off and the float chamber had plenty of fuel in it.

Thank you for your input

regards

Stephen

Did you test the fuel tap operation? it seems strange the plugs always seemed so dry.

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Did you test the fuel tap operation? it seems strange the plugs always seemed so dry.

Yes I did check the fuel tap operation same as on my little 50cc Suzuki.....ON RES PRI when on PRI fuel flows freely into carb, turn to ON or RES once bike starts, yes I thought it strange that plugs where dry but if you read my posts even after turning the bike over for at least 30 sec's with choke full on and twisting the throttle no smell of petrol from exhaust and front plug dry rear plug smelt of petrol but dry, both tested on a dry cloth. When I stripped the carb down some of the jets where pretty clogged and the float bowl was pretty crappy.we will see tomorow when I fit the carb back on.

regards

Stephen

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yeah its defiantly sounding like your piston rings. (having choke on when trying to start but no fuel getting through, cause your rings are shot its going into the sump) its up to you but you could either put it all back together or you could leve it striped and sort the rings out. its not a big big job to do them yourself just a little awkward if you have never done them b4, but your in luck i can go through it with you step by step if you want to try it yourself. all you need is a decent socket set ( 10mm, 12mm and 17mm ) a srewdriver (flat head) and a set of allen keys (not sure what size think 5 or 6 mm :blink: ) some needle nose pliers and some liquid gasket then about an hour per cylinder (if your quick) or 2 hours per cylinder (if you take your time) if you have a torque wrench then that would b handy (but i didnt use one) but yeah get back to me on this one.

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yeah its defiantly sounding like your piston rings. (having choke on when trying to start but no fuel getting through, cause your rings are shot its going into the sump) its up to you but you could either put it all back together or you could leve it striped and sort the rings out. its not a big big job to do them yourself just a little awkward if you have never done them b4, but your in luck i can go through it with you step by step if you want to try it yourself. all you need is a decent socket set ( 10mm, 12mm and 17mm ) a srewdriver (flat head) and a set of allen keys (not sure what size think 5 or 6 mm :blink: ) some needle nose pliers and some liquid gasket then about an hour per cylinder (if your quick) or 2 hours per cylinder (if you take your time) if you have a torque wrench then that would b handy (but i didnt use one) but yeah get back to me on this one.

Hi Paul

Have everything you said I need apart from the "SREWDRIVER" :lol:

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lol soz was typing in a rush lol have you ever done piston rings b4? and do you want to do it yourself? if so il write it up for you then you can print it off or something when you get round to doing it . :D

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lol soz was typing in a rush lol have you ever done piston rings b4? and do you want to do it yourself? if so il write it up for you then you can print it off or something when you get round to doing it . :D

Hi Paul

Bit of a dilema now, you seem to think its the piston rings and I can see you reasoning behind it so I am not in any way de-crying your thoughts, I think I really need to test the compression myself. Strange that the plugs where dry though and as I said the jets in the carb where pretty much clogged up, I will go and check the oil now and get back to you.

Regards

Stephen

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