CBF 125 cold start issue fix

[mikesaa309]

I had an annoying problem with my CBF 125 awhile back and thought I'd share how I fixed it just in case someone has a similar or same issue with the same bike or maybe other bikes are prone to it too.

The Problem:

So the problem is that when cold the engine doesn't like to idle. You start it up fine and it will idle for a few seconds until it stutters or loses power then just stalls. But will start up again fine. The only way to get around it was to keep slightly blipping the throttle to keep bringing the revs up slightly until the engine got warm. Once the engine was warmed up it would idle just fine. Another thing that would happen is that acceleration was poor. It was worse than normal. You could be pinned back on the throttle and it would not want to go like riding a 50cc twist and go but with less noise. This was embarrassing coming out of college especially as it goes slightly up hill so I need more power to accelerate up it and you'll have people walking home and there's me revving the shit out of it just to make it to 30. Again once warmed up the bike would accelerate as normal.

The Solution:

Me and my dad were puzzled as to why this was happening. We thought maybe the fuel management system was faulty and not supplying the right air/fuel mixture. We replaced the air filter as we read online that if it is dirty it could be an issue. We tried a lot of different things and nothing worked. In the end we gave up trying and took it to a Honda dealer. The mechanic came out and we told him what was wrong and straight away he said "The exhaust valve is too tight" We got it home and we adjusted the tappets ourselves and sure enough when I started the bike up with the engine cold it worked fine. I can't remember if we checked the tappets or not when trying to figure it out and if we did I can't remember why we thought it couldn't have been them.

Anyway if anyone is having this problem especially on a CBF 125 then this is most likely the problem. Also apparently the exhaust valve sometimes tightens up on this bike according to the mechanic.

By the way if anyone has an issue with a CBF 125 feel free to ask I've had near enough every problem under the sun with it but then i do ride it far too much for what it is. Most likely worn it out doing around 30,000 miles in a year :/

[davebike]

Air filter / plug ??
Oil clean and the right level ??

Dave
____________________
Dave
NC750Xdct + others at work !
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