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New Member Introductions / Well hello!
« on: July 03, 2018, 12:59:08 AM »
Hello from a slightly desparate recent Honda enthusiast.
First of all, I have a little CB125j 1978, no cb750 as most on this forum seem to have (or is that the wrong impression?), so I am not sure if I qualify. Single overhead crazines yes. only 125cc's though.
To make my commute more fun I have bought a cb125..... hahaha
No real experience with motors, I didn't have a cbt yet, bought it on eBay and had it delivered. Arrived and even though I was over the moon, I didn't really know how to start it or change the gears... read the owners manual, got my CBT, great fun.
It was running quite rich though and the big heaps of smoke following me around, people desperately overtaking me and pinging sounds lead me to believe there was an issue. When it started to stall I blamed it on overheating. Adjusting the floats after carb cleaning fluid in the petrol helped to make it run lean. But there was still oil on the spark plug...
I took the engine off, it sat in my garden for two weeks while I studied all I could find (Haynes, fora) about the engine and got started on it. I had imagined that the valve seats were leaking and indeed the o-ring under the intake valve was pulverised. There was literally a pool of oil on the piston. The pistons were caked, piston head also and I spent many hours cleaning/polishing them. Got one of those suction thingies with the grinding paste, voila.
The sides of the cylinder wall looked smooth and as the bottom part of the cylinder didn't come off at all I left it at that.
I put it back together, made a few mistakes... but in the end got it in one piece. It worked! that feeling.... prouder than a monkey with three dicks.
That feeling didn't last long. Although it did pass the MOT and I could ride it to work it started cutting out after a while... new points, timing set, gap set, valve clearance re-set. still hiccuping after 5 minutes of riding, or sometimes just flop dead. New condenser, same problem, new coil... same problem.
I love that little bike, makes me happy, people smile at my when I pass them on my orange machine.. but my problem is, I don't have a place to work on it, I do it on the sidewalk in front of my house in the evenings... and I need it to get to work... Ok, bad choice to get a 40 y-o bike for commuting but I don't believe in spending money on something I'm not super excited about.
So here I am in a last call, am I overlooking something? Or would it be as simple as a leaking gasket.... I hope not, really don't look forward to taking off the engine again..
Peoples' stories on fora have helped me a lot to avoid and/or solve mistakes I made. Someone offered to buy my bike the other day, as is. He would take apart rechrome redo everything and sell it... I know I should sell it sooner or later, but I really don't want to. At least not until I have fixed it and enjoyed it a bit more.
If anyone could share some of their experience and knowledge to help me solve this "mystery" I would be more than grateful.
So, it cuts out; when it cuts out the blinkers don't work, but the normal lights do. I can normally start it by kicking with the choke on and taking it of quickly. After that it'll ride for less than a mile before it cuts out again. Normally cuts out when I am coasting. Battery seems healthy at 6.7 volts.
Any help greatly appreciated.
Cheers!
First of all, I have a little CB125j 1978, no cb750 as most on this forum seem to have (or is that the wrong impression?), so I am not sure if I qualify. Single overhead crazines yes. only 125cc's though.
To make my commute more fun I have bought a cb125..... hahaha
No real experience with motors, I didn't have a cbt yet, bought it on eBay and had it delivered. Arrived and even though I was over the moon, I didn't really know how to start it or change the gears... read the owners manual, got my CBT, great fun.
It was running quite rich though and the big heaps of smoke following me around, people desperately overtaking me and pinging sounds lead me to believe there was an issue. When it started to stall I blamed it on overheating. Adjusting the floats after carb cleaning fluid in the petrol helped to make it run lean. But there was still oil on the spark plug...
I took the engine off, it sat in my garden for two weeks while I studied all I could find (Haynes, fora) about the engine and got started on it. I had imagined that the valve seats were leaking and indeed the o-ring under the intake valve was pulverised. There was literally a pool of oil on the piston. The pistons were caked, piston head also and I spent many hours cleaning/polishing them. Got one of those suction thingies with the grinding paste, voila.
The sides of the cylinder wall looked smooth and as the bottom part of the cylinder didn't come off at all I left it at that.
I put it back together, made a few mistakes... but in the end got it in one piece. It worked! that feeling.... prouder than a monkey with three dicks.
That feeling didn't last long. Although it did pass the MOT and I could ride it to work it started cutting out after a while... new points, timing set, gap set, valve clearance re-set. still hiccuping after 5 minutes of riding, or sometimes just flop dead. New condenser, same problem, new coil... same problem.
I love that little bike, makes me happy, people smile at my when I pass them on my orange machine.. but my problem is, I don't have a place to work on it, I do it on the sidewalk in front of my house in the evenings... and I need it to get to work... Ok, bad choice to get a 40 y-o bike for commuting but I don't believe in spending money on something I'm not super excited about.
So here I am in a last call, am I overlooking something? Or would it be as simple as a leaking gasket.... I hope not, really don't look forward to taking off the engine again..
Peoples' stories on fora have helped me a lot to avoid and/or solve mistakes I made. Someone offered to buy my bike the other day, as is. He would take apart rechrome redo everything and sell it... I know I should sell it sooner or later, but I really don't want to. At least not until I have fixed it and enjoyed it a bit more.
If anyone could share some of their experience and knowledge to help me solve this "mystery" I would be more than grateful.
So, it cuts out; when it cuts out the blinkers don't work, but the normal lights do. I can normally start it by kicking with the choke on and taking it of quickly. After that it'll ride for less than a mile before it cuts out again. Normally cuts out when I am coasting. Battery seems healthy at 6.7 volts.
Any help greatly appreciated.
Cheers!