Kelum

Hi Guys... When I ride my xv125 I feel the engine goes off few secs and then catches again...When this happens in the traffic when you go slower the bike stops...when starting again it starts as if there werent any issue.. I thought it was the CDI, so I swapped my it with my other bike's....problem was still there. Then I thought it were coils ...swapped them with other bike's ..... problem still there. When I checked sparking, I have seen the spark stops sometimes.. Plugs are new, carb doing ok, new rods and piston rings.. My culprit I think most likely is the pick up coil....as I feel, the problem comes when engine gets hot... Pick up coil continuity is ok, it doesnt short the crank case... Anyone have some idea of its resistance values so I can check... Your suggestions on this will be highly appreciated..

Hellow?

Hey DT do you copy?

Well, you know it all started with the worn out plastic wheel of oil pump you know..engine ceased as I was riding one night around 10.30 pm far away from home....happened in an area you had only coconut lands....It was scary...after the cease I tried really hard to start it thinking it was some minor issue.. Then at the garaj nearby next day the guy tried to start it...actually it was starting but without oil running engine was two tight..He gave up! Then I took it to another mech who worked on carb, and tried full time to start it....actually it did start and had few runs also...it was at his I first heard this strange fut sound once...he opened the engine on my force ( he didnt like opening it as he didnt suspect it was some serious issue ) However, I forced ad we got to know oil sump filter was clogged and the pump wheel was shot and in oil there was worn out metal...we installed wheel and bike was starting on and off...problem was still there...they didnt think they should install new rings... Then I took bike to the mech who fixed my other bike really well..He removed all the engine parts and there was a small play in rods.. we put new genuine rods...bought rings matching the bores at the vendor but after installing all 5, the mech said it was too tight...so he said he would mix new with old at each piston and we fitted the engine...initially it started really well..but not for long ...since engine was ok I thought various reasons were behind not starting...After fitting the engine was of course rough and noise was strange..some deep steady on with some fut fut beat...mech cleaned all the valve deposits to offer perfect shut...He said we would put rings this way and see...the strange noise and poor pick-up..reluctance to start...now am pretty sure its due to this ring problem...I told him and said we should install new rings...He agreed..

Actually I bought two new ring sets...but when mech tried to install them, he figured out that the piston was not moving up and down with required amount of friction..he said with new piston rings installed, it was too tight...so he decided to leave a one or two rings as it is, which means he let few old rings to stay there...I think this is the reason for entire thing...I dont think the strange fut fut coming from top..not tappets...in virago xv125, this exhaust opening is the original setup...you cannot fix it...the barrel left open...but in my other bike I dont get unburnt fuel/oil smell even though the same place is open..with everything checked so far...this seem to be the issue..if it were a carb issue...it wouldnt have come this far...probably one of many fixes I tried so far would have solved it...

I went through some low compression symptoms...as I feel everything works fine... Last week bike was startng and today when I cranked it didnt... I forgot to mention the rough uncontrollable kinda start..and the very strong oil burn or unburnt oil smell comming from under your seat where there is an exhaust opening next to rear cyllinder head..its so strong that when you rev the engine you feel very dizzy...engine has some strange noise and roughness when it runs...this is not the case with my other bike...and I really feel the bike is trying to start when I crank...... When the mech was going to install new rings, it wasnt possible as they made piston's up and down movement very difficult, so his idea was to use the same old rings with 1 or two new combined...Bike doesnt start due to low compression...it starts sometimes though...what do you think?

Hey DT, you there?

I went through some low compression symptoms...as I feel everything works fine... Last week bike was startng and today when I cranked it didnt... I forgot to mention the rough uncontrollable kinda start..and the very strong oil burn or unburnt oil smell comming from under your seat where there is an exhaust opening next to rear cyllinder head..its so strong that when you rev the engine you feel very dizzy...engine has some strange noise and roughness when it runs...this is not the case with my other bike...and I really feel the bike is trying to start when I crank...... When the mech was going to install new rings, it wasnt possible as they made piston's up and down movement very difficult, so his idea was to use the same old rings with 1 or two new combined...Bike doesnt start due to low compression...it starts sometimes though...what do you think?

Yes, must do that....will do the tank that way....and saline system... Yep I have two bikes...one am riding has a very tough bus hose fitted between carb top and bike frame to allow air from air filter come in...I dont wanna toy with it as it was very difficult to fit in even for the mech...Otherwise I would have tried that bike's carb with this one already....Dont wanna toy with it mate, I mean it...dont wanna let her fall and stay home once again..

Yes I agree regarding bike disassembles... I always kept the bike at PRI...I didnt see an issue regarding flow, but must check if rusty debris in tank blocking the required flow...Is it ok to add petrol into tank, shake well and remove, will it flush the tank? I blew air through carb gas feed line and tested floater valve open, closed positions rotating the carb...no problem with close/open.. I think what you say has a point.....lets see....thanks for the time...

Ok....but here in this particular place they buy bikes even if they are working and disassemble and sell parts at a lower price but the ultimate of all parts will exceed the price they bought bike at...Its a business they are doing... Last time as you suggested, I poured a teaspoonful of petrol from top of the carb and bike started right away..So I thought carb was faulty....thats why I bought another...this replace seems to be better than the original... Bike is 42km away at my mom's place, am at wife's place now..but going there once a week...pls log in everyday or I'll PM you when going there so you could stay in touch..I must clean the new carb very well...I didnt do tht, just installed...lets see that tooo...

Thanks a lot DT....my point is that I have replaced the whole carb and the bike still having issues...at least one carb has to do the thing right...now I feel like some tappet issue...but still why does the bike start on and off...? When you leave the bike for say 15 minutes and crank, it would try to start...but wont hold on, the second time you crank, it just cranks...no starting attempt at all...so this suggests me that leaving it for some time kinda seeps petrol in slowly...I dont know I feel it that way...I dont think anyone has played with floaters...no sign of bending etc...so I think all are at original settings...to be exact DT, the bike has been down for more than 1 year now...

Can someone tell me about the function of the 3 jets inside float bowl? The two bigger ones dipping in petrol it seems...the petrol level inside the bowl could be estimated by the upper lift amount of the floater right? at this level however, the smaller jet at left does not seem to be able to suck in petrol...is that the one causing issue? What does this jet do? As I have marked in the pic above, if I take the lower edge of floater as the petrol level, when floater shuts the petrol flow into carb bowl, this little jet at left does not dip in the petrol, so what is the function of it?

Hi guys.... Just to wrap up, my xv125 engine ceased as the oil pump wheel was worn out and the oil wasnt circulating inside...Then I replaced piston rods, piston rings and wheels with genuine Yamaha parts. Replaced manifold joint and it was not fitting well. So placed some spacers with gasket material cut accordingly between engine head and manifold joint. Bike started well after this but after sometime started to just crank like fuel starvation. I bought another fitting manifold joint and replaced non-fitting with it. Tried to start...Bike would start for sometime at first crank, however, it would not start later... I thought my carb had issues, cleaned it with carb cleaner, checked the needles, diaphragms,,, all were ok, float was doing its job right... Starting problem went on, I thought carb was faulty...bought a good condition second hand carb at 40USD....Installed it and the same problem still exists... According to yesterday's attempt, when u push the bike at first gear, bike tries to start but wouldnt hold on...when cranking it sometimes start...not always...when starts you can ride it, it revs better.. When it stops starting, if you let her stay like that for say 10miuntes at PRI and crank, for few secs the engine struggles to run....but wont hold on, sometimes she starts ok...Its like when you keep the bike stand still, by some means some petrol finds its way to inlet manifold and when I fire it burns for few secs...but it wouldnt happen continuously... membrane has no cracks, membrane piston is ok...float is hanging freely...its needle too ok... Two longer jets in float bowl dips ok in petrol at float's closed position...what does the shorter, smaller left side on do, it doesnt seem to dip in petrol...what does that jet do? To me however, this seems to be a petrol starvation issue...cos for the second time the mech confirmed timing and tappets all ok...

I always believe that I should be an all-rounder, you know jack of all trades...It makes you least rely on others...

Hello beemer, thanks for the advice buddy, the thing is these bikes are not very common here and unlike in your countries they practice it by experience...most work on Indian crap...I take bike to them when there is something I cannot handle only...actually engine opening, rod fitting, rocker arm fitting etc were done by a mechanic...last time also mechanic and I did the overhaul and fitting...They work on Japanese bikes but the experience is less on them..but the guy did a good job...also these guys do not have proper tools so when ripping off he damaged some parts and I had to take those parts to soldering and lathing...all by hand...even though he does a great job actually... The other problem is he wouldnt at least roughly specify a date he would fix and return...I will always have to be there for get him to work on it..if am not there he will simply leave it like that...last time I spent months of time there...that was a waste...you dont know what it feels like, there is no proper place even to sit...so as a whole, loads of issues...he's the only one working there..anyway I call him and get his advice ....sometimes he's drunk Am not disrespecting him but with all the probs above it is better I nibble with it and with advice guys here give, fix the problem... Sometimes if you take the bike to mechs, they just make it run without a lasting solution and give it to you...We know the symptoms better and at home you have enough time day and night to play...

The reason was I absolutely didnt think floater did not have something to do with the issue...and when I compared the two floaters , they looked different..I thought I should keep the old one.. Actually, both carbs are used ones...new carbs arent available here...the are on ebay.. I should put the old new arrival's floater and will update you...hope it will heal the issue..

It was tea brown....I put new plugs in and cranked to notice that there was no discoloration which means there was no burning inside...plugs sparking ok so the fuel does not go in to the bore... seriously the carb does not feed the engine for some reason...as I remember, when I replace the carb, I placed old carb's floater in the new carb....I'm guessing I should swap floaters and see...

I thought the same regarding the compression....How can I check it? The finger on plug hole method? Well the sparks...when I put a teaspoon of gas directly into carb, the bike starts... what do we have here...? carb not delivering gas into the system right? In that case the sparks should be ok...I checked the sparks they jump from wire to crank around 10mm gap...so it cant be weak... I feel like someone has toyed with floater level adjustment..like the jets do not immerse in gas in float bowl?

http://www.graniterock.co.uk/400manuals/Miscellaneous_Carb_Questions_FAQ.pdf Every biker should go through the above PDF...Reading tomorrow, hope it will bring me solutions....

Problem is still there...I replaced the old carb with another disassembled one and bought another used manifold... She tries to start..but doesnt hold on...still the idle screw setup is confusing....Like dt502001 told, idle screw should be the issue? Removed air filter and cranked to see if its the cause. NO What if the float chamber does not get adequate fuel level to immerse jets in gas so the jets cannot suck in? I feel suicidal...it has been more than 1 year now, still struggling with this stupid bike..

Hello...thanks for the comment old1eye.. Bike didnt start long even with choke.. I bought a used carb and a manifold...with carb alone fitted she started a bit but not for long, then I thought the manifold had leaks so I bought a good condition used one, installed manifold today.... Bike tried to start several times but didnt hold on...I am totally lost, carb bowl receives gas...removed air filter and cranked to see if it was blocked...no it didnt start.. I found the crank breather pipe was loose...it had a crack...since it goes to the frame...would it be the cause? It appears to me the bike does not suck fuel in...but what is the cause.. I checked for sparks, they were ok...CDI unit properly fitted... All I see is the vacuum created by engine to suck fuel in is nor enough...the crank case breather should be the reason? pls help..

I agree... There was a capacity limit for bikes in Sri Lanka, recently it was lifted, but still I dont see bigger bikes on the road... Honda steeds (400cc) and rarely xv400, xv535 and XV750 are there, most are unregistered or registered as 250cc bikes.. Wht about widening 1.5" from each side...will it kill the bike? thanks...

Thanks for the response mate, I thought the same anyways...I will see what's possible...are those tires very much heavy? Friction should be low though cos the area that touches the ground is very small...I dont know of the weight... Its a beautiful mod mate...

Hiya Guys, What changes would you have to make to your existing xv125 to have wider rear wheel, and may be matchingly wider front wheels too...? I know the swing arm should be wider to accommodate the big wheel... To widen the front sprocket arm and you gonna need some trick.. Has anyone done this mod? pls advice..Thanks..