suzuki vl 125 problems

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suzuki vl 125 problems


im new to the site, i just got my first bike- a suzuki intruder vl 125, but im having a problem with it and i deseperatly need help,

the bike wont start by normal means of pulling the clutch in and using the electric starter, ive checked the engine cut off switch is in the correct postion, the bike is turned on and with fuel in it, and the lights etc work but it just wont spark up!

i can get it started by using a screw driver on the the two points near the battery to short circuit the bike- and this way it does start and run fine but of course i know this isnt good for the bike and is very annoying!- ive been told it is the 'solenoid'? but me being a complete novice i dont have a clue any advise?

cheers in advance

Hi I've just bought a Suzuki vl 125 Intruder, after a few days i was not able to switch gears, only between 3/4 works, have fitted a new clutch which gave some improvement, but gears still seem to be sticking?, I haven't got a clue, can anyone help, please.Thank you in advance

Can you change gears with the engine off, and rocking the bike backwards and forwards?Is the clutch generally working OK otherwise? Are the gear lever & any shafts / pivots  clean, lubricated & moving freely?

Here on behalf of my son.....he's got a 125 cut out whilst riding along, will turn over but not start...battery is fine, plugs fine, even got a new cdi....still no joy.... any idea's.....please

Thanks Helz

Combustion requires 3 things:Compression. Fuel.  Sparks at the right time.Is it actually sparking? Take a spark plug out, plug it back into its HT lead, hold the plug threads firmly against bare metal on the engine and check it's sparking as you turn the engine over. If yes, is it a good, fat blue spark? Then lift the plug off the engine *ever* so slightly, and gradually increase the distance between plug and engine to guage how far the spark can jump. Next - has it actually got fuel in the tank? If yes, is the petrol tap in the right position? If the fuel's low it might need to be on "res". Is fuel getting as far as the carb? You should be able unscrew the drain screw at the bottom of the carb float bowls. Preferably with a small plastic tub beneath them - that way if there IS fuel in there (there should be) then you can also collect it & check it's condition - looking for dirt, rust, water, emulsion etc.Should only take half  an hour to check those carefully (check the sparks first - BEFORE you're surrounded by petrol vapour)... Also, you DO need to check both...

Thank you, appreciate your help......told him to buy a Honda

Just in case anyone has a similar prob as above.....turned out to be a corroded wire to the side stand.....I know!!! not summat you think of instantly as the bike cut out as he was riding along....have since heard of another suzuki intruder having the same prob, so worth bearing in mind

That's unusual - generally if the side-stand / clutch / neutral inter-lock circuit isn't working the starter motor won't turn over either. If I remember I'll take a look at a wiring diagram and see if it should behave like that.

does the suzuki vl 125 intruder have a problem with over fueling? mine hasnt stopped doing and cant figure out why. end up thinking we've sorted it and it will be fine for the rest of the day and the next if im lucky then starts over fueling again and cuts out on me. we've checked the carbs and it seem to be fine no bits of crap in them and parts seem to work ok, the tank is fine. there just isnt a vacume i have to shut the fuel supply off all the time with the tap. boyfriend thinks it may have something to do with the needle in carbs as it should shut off the fuel supply automatically BUT it doesnt. anyone offer me some advice?

First off, what makes you say it's over fuelling? What are the symptoms? When did they start?Second - yes, if it is over-fuelling then it's likely to be the float valve (not the needle jet). This can fail to close because of dirt in the valve, a worn valve, an incorrectly adjusted float, or a punctured or aged float.

hi im having the same problem Helz had. how did you fix it? please! its driving me to distraction!! 

When you say "same problem" - presumably you mean "cutting out while riding along"? That could be a LOT of things. Is it very sudden & random? Or does it stutter and die over a few seconds?

Cant get a spark out of my intruder 125. just wondered if anyone has any ideas on how to check the cdi unit? im a bit desperate to get it running.  i have a megga steep drive so i cant just wheel it into the van. just thought someone might have a procedure on what to do first. i have a workshop manual coming but i will be twiddling my thumbs for the next few days. appreciate any advice

CDI units are pretty reliable - it's the connectors in the electrical system that are the least reliable parts what have you tried / tested so far? and how?

well ive not done anthing yet. i think its an o4 or o5 and low miles. it has been left outside for quite a while, nearly a year so maybe i should look at the connector first? i dont have a spark off either coil so doubtfull both coils have gone out the same time im guessing. im hoping when i get the manual delivered it may tell me a bit more. i really need to get it running for the spring and thats not far away now. l could do with knowing what voltages and where just love to know where to start tappy

i dont know if its a dumb question but would an earlier cdi unit fit on this model. i notice couiple of the numbers are different. i cant get one anywhere and theres one on the dreaded ebay for 150 quid. i have to be quick because they dont seem to become available  

OK, you *could* buy it anyway and sell it on again if it's not the problem. That's your call. Personally I don't think it's likely to be the problem - there are many other things that are more likely to be the problem - many of which result from a bike sitting idle, and "sitting idle" isn't what normally causes CDIs to fail. I normally have access to wiring diagrams but can't find one for your bike, but there are some typical issues: On most bikes, several fuses protect several different circuits. The ignition is usually a separate circuit protected by a 10A fuse. It's unlikely to have blown while the bike's been laid up, but the electrical components on small bikes are quite cheap, and you might find that the fuse box or its terminals are pretty rotten or at least full of water. Worth carefully pulling the fuses out one by one, checking for signs of corrosion and furr and cleaning as best you can. Do this with the ignition off, and ideally with the battery out. The fact that both coils have stopped playing does suggest it's not a fault in the HT circuit (HT coils, HT leads, plug caps and plugs). Also, if an HT system isn't sparking outside the engine, then it sure as hell won't be sparking once the plugs are in wet, compressed gas in the combustion chamber! BUT, it actually still could be - it's been laid up so long that one HT lead might've rotted out a year ago, and the HT-cap on the other has given up 2 weeks ago. So, it's still worth popping the HT caps off, making sure the HT-leads aren't rotten, cleaning the lead ends & caps, screwing the caps back on etc etc. Even if it's not the problem - and as long as you're careful - it will only make life easier for the ignition system, and it'll cost nothing. Next - check the battery thoroughly. Have you replaced it? Have you charged it? Has it been on a trickle charger whilst laid up? If not, then that would be the next likely culprit. If a battery's voltage drops below about 10V it can stop the CDI unit charging and triggering properly. When a battery is used to power a starter motor, the current draw on the battery causes the battery voltage to drop. SO, even if you've charged the battery and it's reading 13V without load, it may be dropping too much when churning the starter motor. A battery that's been idle over a winter or two may have built up a lot of internal resistance so it'll hold a charge OK, but the voltage will drop badly when you demand something from it. If you have a multi-meter, set it to 20V DC, and note the reading across the battery with the ignition off. Then turn the ignition on, and the headlight to main beam, and see what it drops to. Come back here with the numbers. If you can get an assistant to help, it's also worth turning the headlights off and hitting the starter and again seeing what the battery voltage drops to. This is hard with only one pair of hands, and a cheap multimeter may simply jump around and not give a decent reading. If you have another vehicle, use some jump leads to connect that battery in parallel (+ to +, - to -). Bikes don't have much space around the battery so be careful to not short the + to the frame. Connect the - first and disconnect it last. Don't have the other vehicle's engine running, and measure the voltage across the bike's battery once it's hooked up. Then try turning the engine over and see if you get sparks or it starts. If the battery's definitely good and jump-leads to another, larger battery don't help, then next possible culprit is the inter-lock and cut-out circuits. This is where a wiring diagram would be useful as not all bikes are the same. The fact that it's turning over at all suggest this may not be the problem, but again - it's relatively cheap and easy to check, and a little careful maintenance is good anyway. Ther

OK - that lot was very wordy, so here's a summary: When checking if there's a spark, leave the plug in the HT cap, and make sure the plug is in good solid contact with clean, earthed metal - ideally scratch the plug against the engine cylinder fins. Check the fuses and fusebox for corrosion. There's probably a main fuse somewhere which isn't the problem, but may be 3 or 4 others, one of which will control the ignition. Remove the spark plugs, unscrew the HT caps from the HT leads and make sure everything's clean, making good contact to good metal etc. Measure the battery voltage with the ignition off, with the headlight on main-beam, and with the headlight off and the starter motor turning over (probably need a 2nd pair of hands) Connect a good car battery in parallel to the bike's (+ve to +ve, -ve to -ve), being careful not to short the live to the bike or car's frame. Do the same voltage checks as previously, and also see if you now have sparks, or it starts. Check that the clutch switch & side-stand switch are working - are the connections furry, do the switches change between 0.7ohms (switch healthy and closed) and open circuit (1--- on the multi-meter). Check that the bike is in neutral and that the neutral light is illuminated. If there is a wire of the same colour to each of the coils (say, they both have an orange wire) check that this is showing 12V with the ignition on. More than that and I'll need a wiring diagram. I've noticed that my previous post got cut short so any questions, anything you don't understand etc, give me a yell. If it's been laid up that long it's likely to need fresh petrol and will probably need the tank and or carbs cleaning out, to prevent a summer of glitches and odd behaviour.

Ah man thanks for such a detailed response. I've been in hospital today just to get a tooth out but bought the cdi unit off a working machine for 79 quid or something so as you say I will bung it back on if not that. I will update you on what I find hopefully tomorrow once I can feel my head! And thanks a lot for giving me somewhere to start.

Ok worked on the bike tonight for a couple of hours. Took tank off. Get to whatever connector I could get to and cleaned and wd40 on connections. The coils are clean and so are all the connections. I could only find two fuses. I'm presuming there's a small box somewhere but will consult manual just got. Changed the cdi unit with one I bought from a bike dealer on eBay. Jumped a battery over the connections to make sure getting the full voltage. Switch is on and the clutch is pulled. Still no spark from either plug.
That's as far as I've got so far. One thing I noticed is that when I switch the ignition on, pull clutch in and with one hand on the relay for the stand and clicking the stand back and forth I don't get any clicking from the relay at all. Not sure wether this could be the problem but I'm guessing I should try find out what's going on there. Feel like I'm getting there. Cleaning all the connections even if not that bad needed a bit of refurb.

Further to the above I have checked all the connections now. Most of which were really clean. I will plug the other cdi back in and try that again now I've gone around it. Kick stand switch is fine and also the relay is ok too. Not much else left. I have to check the voltage to the coil and apart from that I guess all that's left is the stater plate. It calls it the generator in the manual. Unless I've been given a duffer of a cdi. Any ideas if I cn get the cdi checked at a dealer??

That relay not clicking is almost certainly related. Something, somewhere is stopping that relay switching and so stopping the reg/rec firing. Any chance you can scan the wiring diagram from the manual and post it up?

Hi bud just got in from five weeks away working. What sort of picture can I get? The actual schematic or just the set up where everything is. Sorry bout the delay. Hope I can work out where everything goes?
Further to my last message just before I went away I also changed the stater plate which a company down the road did a years guarantee on one of theirs for 45 quid. Said mine although readings were not too bad but was definitely breaking down. Funny enough the woman said it looks older than the bike and wondered if it was from a scrapped bike before. Anyways still no spark. Not much else to replace apart from the whole bike ????

What you ideally want is the wiring diagram from the appropriate Haynes, Climer, or even suzuki workshop manual.  There's a CD-copy of the factory one on fleabay for £7

I have a cd with it on. But can't see how I upload it here? I've taken a screen pic with the iPad too.
I'm starting to wonder if its the cdi and I've been sold a duff cdi off a bike scrappy. Unfortunately susuki can't check the cdi so I'm told. I think I will have to find someone who's breaking a few and see if I can pay to plug both mine in to see if its working. I'm getting power to the cdi as the manual says. Then I guess next I will have to measure to see if there's any sort of output to the coils?

Hey. Have similar problem with my vl125, spark comes and goes. Try to warm up the cdi box with a hair dryer or similar. It worked for me - same problem occurred today, when I warmed up CDI box and then everything was ok again.

That problem at least you know what it is. All you got to do is carry a hair dryer every journey lol. I wish I could just check the cdi.

I have now changed the side stand relay which previously showed as ok. It now has a spark! Can't wait to try start it tomorrow. I'm sure I have a gelled carb now. Hopefully a fuel drain I can flush through a bit. Thanks tappy your long post I read before looking into it couple days ago. Your a legend

Interesting progress Good luck, hope that's what it is...

I'm pretty sure the cdi unit that is the problem.I have now thrown the hairdryer and bought a new cdi unit. 2500NOK = 430 USD

  Suzuki_Vl125_Intruder_Vl_125_99-09_Service_Repair_Workshop_Manual  16494kb  

HI there,I to am looking at an Intruder 125 with no spark.  Just doing some continuity testing, I get a good "beep" when the clutch is pulled (At the switch) and am also getting a good beep when I check for continuity at the starter button (when pushed). I've just tried testing the side stand switch, and although I get a reading on my multimeter of 590, I get no beep.  Is this a good sign or bad sign??    

That rather depends on what units it's set to. 590 ohms, killohms, megohms. If you get 590 "x" in one position, what do you get in the other? Open circuit? Or continuity?

i have had a vl 125 for the last 3 years as for the problem with not starting although turning over and no spark it happened to me on numerous occasions at least twice a year and usually after running head lights all day lol i got a tip from a good bike mechanic who said " sometimes the ecu/ cdi unit on some jap bikes gets cut out of the circuit if the battery level drops below a certain ( inserts something like ohmage amps or whatever) its not the battery and not the cdi or overfueling which i thought at first you have to keep the battery on tip top charge buy a drip charger or battery optimizer and connect the bits to the battery put it on overnight charge once every few weeks or after using lights all day in inclement weather i tried this and not had a problem since apart from when i forgot to optimize the battery .....hope this helps if it does problem solved for 15 quid optimizer    

Hi,  I've got a suzuki intruder 125 which isn't starting right, I am due to put in another reg/rec as it is not charging the battery (tested with multimeter, battery sticks at about 12.4 - 12.6V when bike starts running and give some throttle). However, another problem I'm having is that when I go to bump start the bike so the battery doesn't drain it's sounds as though something isn't moving freely. Usually when i've bumped it in the past I'd dump the clutch lever in 2nd gear and it would start up fine but now if I try and get it to run with the clutch out it's as though it's struggling to start and there's a clicking sound until I pull the clutch in. I think it might be the starter clutch/flywheel but I'm still a novice on this stuff. 

Well done on checking the output with the engine revving, but always remember that loose, corroded or broken wires (or poor earth connections) can cause the same charging problem and are a lot cheaper to replace than a reg/rec. If the battery hasn't been charging then yes - you wouldn't expect it to start well. 13+ V is well charged but 12V is absolutely pan-cake flat, so 12.4 is pretty empty. The clicking sound could be a lot of things depending on how fast it's clicking etc. It could be something as simple as worn chain and sprockets - with the back wheel pushing the engine (it's normally the other way around) the chain may be clicking on the front sprocket, and without the engine running you hear it. To try and narrow things down a bit: When did the starting problems begin? Did it coincide with anything else? Was it running OK before that? Were there any other problems? Etc etc.

Hey, Names Mitch, im a industrial electrician and have a VL250 (same wiring as the VL125) and it has no spark on either cylinder. The ignition fuse is not blown. So far ive disconnected the ignition coils done the resistance checks on the primary winding, it is 2.6ohm and the secondary winding 19.5kohm which is in spec, i took it one step further and put it on my ignition coil driver and i can fire the coils very well for a long time. I also installed new spark plugs on when i was running it on the ignition coil driver and they where firing no problems. I checked for 12V+ at the ignition coil when the ignition switch is turned on and I get 12V+ on each coil, same with the CDI unit. I put the CRO in parallel with the ignition coil primary coils and tested for volts while cranking, manual says it should be above 250V but i get 0V. Next I checked the pickup coil resistance, its 248ohm which is in spec from the manual. I then checked the peak voltage coming out of the pick up coil (as i cranked the engine over) on a CRO and it is peaking at 4.5V which is in spec to the manual. The neutral switch lights up and the side stand relay clicks in and out correctly, also tested the side stand diodes and they had 0.5V Vdrop across them which is in spec.I then concluded that the CDI was at fault, purchased a second hand one for $80 and installed it today, still no spark! Not sure where to head now? Anyone got any ideas?Mitch.  

I can't find a wiring diagram for one of these, but there's often a wire to earth from the CDI unit (usually black & white). Sometimes it passes through the ignition switch and only connects to earth when the key is turned. Point is - if this path to earth has failed then the CDI won't fire. Similarly, there are sometimes wires that go from the CDI unit up to the ignition switch, through a resistor, and back to the CDI or to earth as an anti-tamper measure to prevent hot wiring. Again, if this is interrupted then the engine won't run. If you have a wiring diagram post it up somewhere & I'll take a look. I would also ask: when did the running problems start? If they can be tied to an event or period then that's generally a good clue.

OK - I found an entire service manual instead. There are two black & white wires from the CDI. One goes to the pulse generator (which you've checked) and the other to earth as I said. There's an orange and red wire that goes to the ignition and then back to earth via a black and white wire. Where there's a resistor in the switch I don't know - you obviously know what you're doing enough to test for resistance across the switch! Most of the other circuits you've already tested, but this diagram also shows a throttle position sensor. I'd only expect this to modify the advance curve, not stop it firing at all so I doubt that would be the problem. Other than that it's just the usual looking for corroded connections etc between the CDI and the various items that you've tested.

I've had a Suzuki vl 125 for about 6 or 7 months now and can't imagine riding anything else. But recently it's developed a bit of a problem which I'm hoping somebody might be able to help with!
Bike works absolutely fine when running and moving so no trouble there. However when I go to turn the bike on, I get a horrific squeal from the front of the bike and sometimes it doesn't turn over. Fresh spark plugs, battery, oil change and filter, and I'm not sure where to go with this!
Like I said I've only been doing the whole "bike thing" for about 6 months so I'm not too experienced with the more detailed problems. Maybe someone here could give me some advice before I take it to the dreaded mechanics!!

I've been riding my vl 125 for about 6 months and it's an amazing bike but recently developed a problem which I'm hoping someone here might be able to help with!
Bike rides like a dream and sits at idol fine so no drama there. However recently whenever I start it up its developed quite a violent squeal from the front of the bike and sometimes it won't tick over. Really sounds horrible!!
I've recently replaced oil and filter, battery, spark plugs etc so I'm at a loss. Like I said I've only been doing the whole "bike thing" for about 6 months and I'm not sure on a lot of the more detailed problems. Maybe someone here could point me in the right direction before I have to take it to the dreaded mechanics!!

You say "whenever I start it up" - do you mean that the squeal lasts about as long as you've got your fingers on the starter button, or does the squealing carry on for a bit? If it carries on and won't tick over then that's likely a leaking head gasket or a cracked cylinder head OR - a spark plug that isn't tightened correctly.And by correctly I mean seated squarely, threads lubed etc, not just "not tight enough". They're quite tricky to do sometimes. If you didn't clear the spark plug area properly then maybe it tightened down onto a bit of dirt or something? Best bet is to carefully clean around the areas, then un-screw it, remove it, inspect everything, and insert / torque it as per the instructions.    

Literally just when I turn it on. Just a loud squeal when you press the ignition then as soon as its ticking over it stops. I'll give the spark plugs another look and make sure I did them properly

Well if it stops once it's ticking over then that sounds like a problem with either the starter motor or the starter motor sprag clutch (the bit that lets the motor disengage once the engine's started). So when will it "not tickover"?

Hi, New to biking, recently bought an Intruder vl 125 and would appreciate any advice on a problem I've got with the throttle/engine response. It starts up fine, sits idle with what seems like no problems but when engaging the throttle there is a definite delay in response and is sluggish....Any ideas? Thanks

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