Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

Featured Strange hiccup on my commuter ....

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by jord4231, May 22, 2015.

  1. Hi netriders.

    My little cb125e around 7-8months old 6000kms on the clock has started doing something strange

    It only does it at full throttle although I must admit I ride it very very hard.

    Occasionally it has a little "hiccup" I'll be riding a long full throttle and its like it has a very brief sudden surge of power almost like slipping the clutch briefly but not quite,

    The clutch has not been abused or slipped and its functioning correctly.
    Its had all its services.

    When it first happened it felt more like a engine miss, when it did it tonight it was like a 1 second small turbo .

    Now I'm wondering if I'm hitting a small bump in the road and loosing a little traction although I doubt it
    Or is the clutch having a moment
    Or is the engine smelling my farts and having a momentary boost?

    This surge is very brief and nothing continues to slip or carry on , and its not happening a lot but maybe more often than it used to. Not even once a ride some times not for a week or more

    Anyone have any idea never experienced anything like this before unless it has been deliberate clutch slipping on bigger bikes
  2. This is not a tech answer, just thinking out loud.

    Yes it's a Honda, but very small capacity, built to a (very reasonable) low price.

    The fuelling is not going to be world class and the hiccup may just be a normal response to being ridden harder than the designers intended.

    Happy to be proven wrong.
    • Agree Agree x 1
  3. Not really sure what to think. its a carby bike it could have some thing to do with it if only it had that surge all the time lol
  4. Maybe ask it to hold its breath for 30 seconds. It helps me when I have hiccups. :)
    • Funny Funny x 2
    • Like Like x 1
  5. They are single CV carburetor I believe.

    It's difficult to know exactly what you are seeing. Do the revs jump? Does the bike speed jump?
  6. cjvfr if you have ever been on a bike or even in a car for that matter that has a cylinder not firing due to being flooded or a bad plug and when it starts to clear up you start to feel it kick in. That's the sort of thing I'm getting (not that its running badly, its running perfectly)

    I guess the revs are jumping a little and then back to normal very quickly the bike doesn't have tachometer

    I really don't know how to explain it better I feel silly its something that in 10 years of riding I've never experienced anything like it.

    its possible that I am just pushing the bike so hard its hemmeraging a little
  7. I was thinking about it today, I'm starting to think I'm running out of fuel in the carb bowl and it runs lean for a second maby the fuel filter isn't up to it...
  8. Maybe:

    Float Bowl settings set to low perhaps??
    Fuel pump issues??
  9. Fuel bowl too small I think perhaps no fuel pump gravity fed..... stupid gravity :p
  10. Ah that will be it then, Low Gravity areas ;)

    Seriously though carb float height setting is a possibility.
    • Like Like x 1
  11. Definitely agree cjvfr when I pick it up from the side stand quickly it want to stall....
  12. I bought one of these brand new in 2012. I put 10600kms on it before I sold it (got my full licence).

    Mine never hiccupped as you describe but certainly ran very lean. Yes it is a CV carb

    Longest I held mine flat out was down a hill for about a minute. 108km/h

    You could try to richen the idle mixture by unscrewing the mixture 1/4 to 1/2 a turn. This would at least help the idle and low speed running (and cold starts, They love a lot of choke)

    Do yourself a favour and run 95 ron petrol. I ran mine on mainly 91 (cold starts are easier) and when I replaced the spark plug at 8000kms, it had signs of detonation in the form of small molten bits of aluminium from the piston!

    How old is the fuel in your tank when this happens? I used to get around 400 odd km's from a tank (about 2 weeks worth of running) and by that time it was starting to go off because it miraculously started easier and went a little better after I filled up with fresh fuel.

    Being very low power (10HP) they are sensitive to fuel going off.

    A bit off topic, but good tyres for this bike are Michelin M45. 2.75 x 18 front and 3.00 x 18 for the rear. Soooooo much better than the crap kenda tyres.

    • Winner Winner x 1
  13. Thank you very much for your post hornetS. I ride this bike every day fuel is usually 2-3weeks old tops I get about 500kms until reserve and run 95 because it runs a lot better.

    So far usually find the bike feels like it goes better when the tank is low (I guess the weight reduction)

    I've held my bike flat out for at least 15 -20 minuets at a time 5th gear on the highway although don't get me wrong this is not a bike I want to ride on the highway this is just my secondary commuter toy that occasionally I need to go down the highway with for what ever reason.

    Also having said that I ride my bike basically full throttle all the time.

    Mine has an aftermarket exhaust so it could probably do with being run a little ritcher.

    My bike has always started very easily although yes I use the choke in the cold mornings.

    Detonation Ouch I've only just hit 6000kms I'll have to check that out.

    Glad you mentioned about the tyres because the stock ones suck! Thanks for the tip!
    I've always said I can't wait to replace them
  14. Mine went better when I went on a diet and dropped from 85kg to 72kg :]

    One thing I didn't try was a colder range spark plug. The standard one is CPR8EA but a CPR9EA might be a bit better for your highway runs.

    I did have an aftermarket exhaust (screaming demon from W.A.) for a few weeks but took it off as the noise got too much. Did nothing for performance.
    If you still have the standard exhaust, put that back on to see if it still hiccups.

    Another thing is the engine oil. Honda recommend 10w-30 but I found the engine ran much quieter when hot with a 10w-40.
    The extra viscosity when hot was much better for the little air cooled engine. The gear box felt better too.

    I also changed the oil every 2000km. At a litre of oil for an oil change, it is cheap peace of mind.

    • Agree Agree x 1
  15. Yes I totally agree, the exhaust does little for power mine isn't overly loud but at least cars can hear me now Nearly got hit a few times when it was quiet.

    I was just thinking the other day being I ride it so hard I might do the oil change early every 2000k is exactly what I was thinking

    I'll give the 10w-40 a go next change this coming weekend I would say.

    Speaking of diets I need to get my head out of the feed trough I'm back up to 85 argh!
  16. Hrmm perhaps it is not a fuel issue, I did an oil change on the weekend
    I also tightened and lubed the chain, Hasn't done it since so not sure if it was the oil or maybe the chain was even jumping! it was fairly loose but not crazy loose
    • Informative Informative x 1
  17. Maybe the chain adjustment helped.
    Do yourself a favour and get a good o-ring chain for it (428 size).
    They last a lot longer than the standard one (non o-ring).
    My standard chain developed tight spots in the links after about 2000 k's.

    • Like Like x 1