HELP I DONT KNOW WHATS WRONG WITH MY BIKE!!!!!!!

hello everyone! just registered due to not being able to find the problem with my bike ANYWHERE else on the net. so here goes, its a Pulse Adrenaline 125cc, everything on it is completely fine, had new tyres fitted new solenoid fitted new brake pads had the carb professionally cleaned, so basically it starts with the choke up and runs and idles fine, leave it for a few minutes to warm up, take the choke off and all is well. until i turn the bike off, it then will have trouble starting with the choke on or off, sometimes it wont even start. it cranks but wont fire up sometimes, choke up it starts choke down it starts after its warmed up, so one minute it will be all good, the next time i start it up it ill sputter and bog down and eventually die with the choke up, take the choke off, it dies almost instantly sometimes will stay running for a good minute or so but eventually dies. one day it absolutely fine the next its a piece of crap, has new spark plug, new battery too. if try the throttle too soon it will bog down until it dies unless i release the throttle. had the carb cleaned then i mixed some carb cleaner with the petrol and it smoked like a trooper so i assumed it worked. but still the same problem. any ideas and how to fix this? there is also a small pipe just under the carb coming from the engine into the air box, it has a split. can this be my problem? if not WHAT IS IT?

oh and also it is only one year old i think it was brought around january-february last year. only has 10,000 miles on the clock.

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Originally Posted by Dodgey2013

there is also a small pipe just under the carb coming from the engine into the air box, it has a split. can this be my problem? if not WHAT IS IT?

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I don't know this particular bike, but several others on this site have it so they may correct me.

1) That sounds like your CCV (Crankcase Ventilation) return line. It takes gases/fumes out of your crankcase and recycles them. Yes, you should replace it.
2) Overall, it sounds like a fuel problem. Is there water in the fuel? Any gunk/pieces of rust inside the tank that may be interfering with the feed through the petcock? Clear breather/gas cap? (do you hear air rushing in when you open the tank cap, during the periods of difficult starting?)

Good luck!

i will replace that pipe on monday as most shops are closed tomorrow but i will check everything else tomorrow fuel has been in there since august as i have been unable to use it because of the tyres, got it done and now this! i think there is a bit of dirt in the bottom of the tank but the petrol has carb cleaner mixed in with it so i wouldnt really like to drain it and replace it in case it is still my carb but if i have to, i will. what does the petcock look like? is it the thing with the fuel thing where you can turn the fuel on or off? i dont know too much about bikes lol wish i did :(

i did also take the pipe that goes from the petrol tank to the carb off, turned fuel on ans the fuel was running out absolutely fine

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Originally Posted by Dodgey2013

is (the petcock) the thing with the fuel thing where you can turn the fuel on or off?(

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Yes.

I once had a bike with a rusty gas tank (on the inside). Little pieces of rust would flake off and obstruct the petcock (bike wouldn't start), until they moved away (bike would start). How is your fuel filter?

When the carb was "professionally cleaned", did they disassemble it?

ok i will check that tomorrow, hopefully its something simple that i can do myself and wont cost me a ton of cash to get fixed! also adjusted the idle mixture screw so it idles better than what it did, where would i find the fuel filter? and yes i took the carb off myself, which was easy to do, took it down to a motorbike shop paid them to clean it watched them take it apart n leave it in ultrasonic cleaner but it didnt look too dirty in the first place but i put the carb cleaner with the petrol just in case. i did remove the carb again and took the float bowl off and blew compressed air into every single orifice in the carb, float is fine float needle is fine adjusted to the correct position.

Just reread your initial post.

So, when the bike is cold, it starts ok with the choke? The problem happens (sometimes) when the bike is warm?

yes it starts with choke up, leave it for a few mins, put the choke down and its all fine, but if i pput the choke down too soon it bogs and eventually dies, if i try to start it after its died is when it has trouble starting sometimes wont start sometimes it will but with choke off it just dies so i leave it to warm up for a few minutes

but sometimes it will start fine choke up or down after its died

Hmmm, sounds like a air/fuel <> rich/lean mixture ummm... I don't think it is worth adding the word 'problem' at the end of that since it sounds more like it is an issue where the engine may not be given enough time to warm up before you push the choke back in all-the-way or in other words return it to the 'off' position.

Out of all my rides, I still have a bike with a choke, my Dragstar 1100. When the outdoor temps are warm (as in the kick arse hot summer one experiences here in this part of PRC) then the choke is only needed for a shorter duration than in the winter which we're getting into here. Snow hasn't arrived here yet, but the worst air pollution I've seen in these parts have (another story).

FWIW with the choke operation on the Dragstar, I apply full choke, turn ignition key on, and press the starter button (no throttle - actually all my bikes I never need to use throttle on start-up). I leave the bike with choke on full for like a minute or two while I put on my riding gear etc. Never ever timed it so maybe more time, maybe less. When the engine is getting warm enough the idle will start to increase on it's own, at that point I will usually back of the choke a tad to find that balance. If it's too cold then the engine will hiccup a little if I back of that choke too prematurely, which it's more likely to do when the ambient temps are also cold like now, and less so in summer. It takes small increments of backing off the choke, until the engine is warm enough to not need it.

I'm not sure OP if this is your issue or not, but try just letting the engine run with full choke for longer, do the RPMs increase when it gets warmer? If so then that is your cue to back off the choke. Rather than shutting the choke off completely try smaller increments towards choke off and see if that works for you.

I did do that earlier today, started it with choke up left for a few mins revved it a little bit, put the choke down maybe a 1/4 maybe a bit less maybe a bit more, and it was fine, took it down another notch after about 30-50 seconds, it was fine, took it down a bit more it was fine, until it was completely off, it was fine. it doesnt always happen but when it does it is a pain in the arse i just wondered if the dirt in the tank could be affecting this and the split in the pipe that i mentioned earlier

^^ what he said +1

After your last couple of posts, I had the sense that you are backing off the choke too soon, and then flooding the bike with too much gas when trying to restart. Tricky to restart a flooded engine, but it usually means you need to use full throttle and full choke to get it running again (it spurts & sputters for a little bit), then back off the throttle completely, and back off the choke slightly, and then manage the running using both throttle and choke.

Really difficult to know via the WWW. Need to see the bike in person, sorry.

i cant always get it to run which is also a pain because i do rely on the thing to get to work and back everyday but thats only a 10-15 minute drive up the dual carriageway so obviously when it wont have none of it i get frustrated and end up late for work cause i had to get the crappy train which is why i need this issue permanently fixed

i will give it another try tomorrow and if it works i will get on it, take it for a ride, empty the tank out and put fresh petrol in and i will also clean the dirt from inside the tank, but if it still wont have it, i will take a video of it and post on here for you guys. Thanks ALOT for the help. much appreciated :)

one more thing, just to be absolutely sure, it is ok to ride with the choke up yes? wont blow up my bike or do any damage i am aware that it can foul the spark plug and such.

Hmm, running/riding with the choke engaged shouldn't really be needed. If you do so for an extended period though you will foul the spark plug.

One thing I read OP, is your giving the throttle a little work out with the choke still engaged. I've never needed to do that, on any bike or car for that matter that had a choke. The only time I might need to use the throttle during use of the choke is when I have backed off the choke fully or too much prematurely. It really is difficult to diagnose anything over the www which is why I don't. Engine's, moving machinery just like humans and other animal species need to be seen directly to really appreciate all the subtleties it takes to make an assessment and get an impression about any issue.

I'd also add that if you are in the habit of starting an engine for only a minute or two then ignition off, then you might end up with certain parameters being met, that lead to a hard start condition.

Ignition on, full choke, press starter, let the engine idle for several minutes or until the engine RPMs increase on their own, then back the choke off a little, wait until the next natural RPM increase with choke still on (though a little less so), and ditto until the engine is fully warm and the choke is not needed. I'm not sure you need to touch the throttle during this warm up period.

If you inadvertently end up with the engine cutting out during this period, and there's a strong petrol odour lingering about, then it's likely you have a flooded carb. WOT (wide-open-throttle) is most likely what you need to use to attempt to get the engine restarted immediately afterwards, and you may not need to use the choke at this point. But, again, really hard to work that out without being there.

If all else fails, take the bike to back to a motorcycle mechanic for a diagnosis etc. Oh, and yes replace that split pipe/tube...

Ok I will post an update once I've given it another go, battery died trying to start it so is on charge, thanks again for the help :)

Just gave it a try, sounded very promising until the choke was down about 3/4 it was sputtering and struggling the revs were climbing but then going back down and climbing until it died

Many years ago, we were struggling with a similar issue on a friends' bike and in the end it turned out to be a "loose" intake valve. After valve adjustment there were no more starting issues.

Btw, ambient temperature and moisture must have changed since the bike ran OK, so it could be poor carb settings, that are simply "amplified" now in the cold weather. When it runs (after it's warm enough and all), does it rev properly? Any sputtering or flats? Can you check spark plug colour?

When I do manage to get it running properly it revs fine no sputters or anything, my dad seems to think there is a flat spot in the throttle but I don't believe there is cause he tried it and yeah it was pretty much like there was a flat spot, but I tried it yesterday and there was no flat spot and when it dies it will either start straight back up if I try or I'll have to leave it for a while before it'll start again

Got it started with choke up, wouldn't idle and died, switched fuel to reserve took choke off, started fine and is running fine and revs fine switched fuel back to prime and it's fine.. Wtf is wrong with it?

Sorry mate, but it sounds like you might have to get a local mechanic to look at it. It would be good if you had a friend with the same bike, because you could swap parts around to see which, if any, are faulty ... or if it is an adjustment that is needed ... or both.

If it was running well back in August, there are a couple of things:

1) as Krasi notes, it is colder now, so your bike will behave differently; and,
2) whatever changes you did between August and December is immediately suspect. It is not uncommon for new parts to be faulty, or the process of replacing the parts somehow knocking something else out of adjustment.

There are so many possibilities that you could be chasing your tail while we offer "Check A" ... not it? "Check B" ... not it? "Check C" and so on. Perhaps unnecessarily replacing parts along the way. An experienced mechanic should be able to quickly figure out the problem(s) on a single cylinder 125cc with the bike sitting in front of him.

My own mechanic rolls his eyes any time I tell him I did some of my own maintenance, troubleshooting &/or repairs. He claims a sizable portion of his work is fixing customers' shade-tree mechanical efforts.

Despite all this, I have a suspicion that your problem is somehow related to fuel delivery (actually, mixture delivery). Because you've R&R'd the carb a couple of times, are you certain that the mounting seal/gasket between the carb and engine is still perfect? If it isn't, it can now be sucking in outside air. A quick test is to spray carb cleaner around the joint when the bike is idling. If RPMs increase, the carb cleaner is being sucked in where it shouldn't be.

Bike is fine now! Must of been a dodgy fuel delivery because when I changed it to reserve then back to prime it started with choke off didn't sputter bog or hesitate took it out and it runs like a beauty :) one other problem is that my indicators and horn don't work but it's weird because sometimes they will just randomly start working out of the blue

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Originally Posted by Dodgey2013

Bike is fine now! Must of been a dodgy fuel delivery because when I changed it to reserve then back to prime it started with choke off didn't sputter bog or hesitate took it out and it runs like a beauty :)

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Very good news. Let's hope it stays that way. Seems you might need to remove and clean the tank.

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Originally Posted by Dodgey2013

one other problem is that my indicators and horn don't work but it's weird because sometimes they will just randomly start working out of the blue

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Easy - check your tire pressure. :icon10:

Seriously, good luck with electrical gremlins. You need patience and a multimeter. If they are on the same circuit (and share a fuse), start by looking for corrosion/loose connections.

Ah it's no biggie actually one of my work mates is a qualified electrician I'll get him to take a look