Got up this morning and scraped the ice of my seat started the bike and all was good. Sounds great eh? No Driving down the dual carriage way and bang, bike seemed to stall i had no power at all. So I think dayum fuel!! switch to reserve and nothing. The bike was still running but the enigne was knocking and would pull with any power. pulled over in front of a speed camera to see what the hell had happened. Re-started the bike and it wont rev over 1k RPM and if i let go of the trottle it just cuts out. Theres mad knocking aswell. So I have no transport and really need some help!!! Is it a simple case of changing a part or two in the engine or do i order one? I need to sort this asap as im working and need to be able to get there! If you guys can try and help that would be amaaaaaaazing... And GGGRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR there we go that the frustration gone well some :S
IIRC, when I was at seabank the other week, there was a 125 in with snapped valves. Engine had absolutely no power, but it could run under idle. Best of luck in getting her sorted mate. She's been through a lot with you! Honda CG125
maybe check the compressing in the cyclinder ??? if its low then you may of bent a valve, head gasket , not that big thou on a 125 .....
did it happen almost straight after riding off? heard before of engine oil freezing up like treacle in ultra cold conditions and the oil pump cant suck it up the strainer... result - bang, always top end that gets it, valve seizes in the guide, camshaft runs dry in its journal etc.... as daz said, not a major job on a 125 single, but still arse
So new engine then? Yea happened like 2 miles into the journey. So annoyed as today was my first day back to work in a week and a half!
the piston could of gone bang i remember many moons ago gp100 comin home from work splutter bang from 60mph down too aprox 5mph managed to get home 1mile and that was the end piston melt rings gone rebore piston rings sell :thumbdown:
have a look at it first m8. simple compression test, take the plug out and stuff a finger in the hole, turn it over. you should be able to feel a good pressure build up. if it turns over with hardly any pressure against your finger then you can safely say the valves are gone. if thats the case its worth taking the head off for a look see. might be a simple job, assuming it hasnt damaged the piston... or you could pick up a head off ebay cheap enough, not a big job to fit with it being single pot & air cooled, no fairing etc, just have to time it up tdc and make a note of the cam position. should only take you a few hrs tops.
right checked the pressure theres loads! O and i electrocuted myself with the spark plug! I rode round the block and its fine up to about 10mph if i pull down the throttle it just bogs down and loses all power... I need this bike by tuesday at the latest please HELP lol
oh yeh sorry, forgot to mention tuck the ht cap well out of the way lol. well at least you know its sparking! and good news is you havent dropped a valve. strip the carb and have a look. be gentle with the float tho and watch the pin that holds it in place (and the needle valve) doesnt drop out. main jet is the central one about 8mm hex (may be slotted) it screws into the emulsion tube that the long needle slides into. your work area must be meticulously clean when you have the carb apart, the slightest grain of crap can cause problems. clean it by rinsing it in clean petrol and a bit of copper wire. dont be tempted to poke a pin through it or a drill bit - you wont make it go faster lol if you get stuck when you're doing it give us a ring - 07810 501053 have you checked your air filter isnt p*ss wet? could be something really simple m8... have a look in the manual in the troubleshooting guide and it will give you a few tips where to start. theres a manual for it in the honda moto link in the online manuals thread - dont worry if it's a different year, the engine & carb hasnt really changed much in 30 years lol
Will check the filter isnt wet tomoro morning as for the carb would it be quicker to buy a new one or try to fix mine? And btw its still knocking when i try to rev up
the knocking might just be 'pinking' cos the mixture is so weak. does sound like fuelling from what you say, very weak. you could strip the carb on that in 30 mins tops. but take your time if youve never had one apart before - dont worry, springs and levers wont pop out all over the floor lol, you will be surprised how simple they are. no point buying bits until you know for sure what the problem is. if its a blocked jet you will be away in no time.
Just downloaded haynes manual so ill jump onto it tomoro I will check the air filter first and oil level too! Strange that all this has happened not long after putting fresh oil in (the bike have almost none for about 2 months!) When i took the spark plug out i noticed it was very very mucky and black on the bottom end! Does that have anything to do with it?
black plug suggests a very Rich mixture or blocked air filter... have you jetwashed it recently? & what happens when you turn your idle up high? you may well just have a sticking choke plunger in the carb. have a look at this site - you may find it usefull for general info http://hondacg125.awardspace.com/ there is a copy of the manual here - http://honda-cg.ifrance.com/Honda-CG-125-1976-1991.pdf
Stop p*ssy footing around it sounds like its propper fucked, if its knocking & theres no power I would start looking for another engine !! Sorry Elliott :banghead:
nah it just needs cleaning.. thats why i asked if he'd jetwashed it lately!! :lol: tbh if you are planning on getting shut just set fire to the fker!
Elliott, Have a go mate, get some decent tools and start working through the easy/cheap components. If it is none of these strip the engine and sort it yourself, I promise you will be ok. LIke Martin said take your time and be methodical. Its the best way to understand the engine and gain mechanical knowledge, plus there is some guys on here that know a lot and are willing to help.
