Hiccup/gasp cruising in 4-5th gear

Maxdar

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I have a 2008 CBR 125, when cruising in 4th or 5th there is occasionally a short hiccup or gasp. I've had the bike about 3 months and put about 1700Km on it, with 2 self administered oil changes and due for one shortly. It had 1700Km to start, I'm the 3rd owner....bit of history never hurts, right?

The gasp is only a blip. I back off the throttle and it has not repeated right away so far. It has happened about 3-4 times. Only noticed it in higher gears and not every time either. I have not been on any long trips, each ride has been about an hour or two at most. Once I got up to Jackson's Point from Pickering and that day I had no issues.

I've googled and read suggestions on missing O-rings or that the bike doesn't like the cold.
 
First change was more practise(first time ever) and I used the wrong oil. Small engine with high revs, I read that frequent oil changes are best way to ensure long term health.
 
Only 3400 km in 4 years? If the bike has sat around for a long time, fuel might have gone bad in the tank at some point. It's fuel injected. Install a new spark plug. Run it as close to empty as possible. Lift the fuel tank up at the front (see owner's manual) and verify that the tank vent hose is not kinked - this is the hose attached to the bottom of the tank at the back close to where the hinge/pivot is. Fill it with Shell V-power 91 (reason: does not contain ethanol), put in a small amount of fuel-injection cleaner (avail at Canadian Tire ... don't forget to proportion it according to your small fuel tank! don't dump in the whole bottle), then run that tank out as empty as you dare.

On those bikes, it's really easy to kink the vent hose when installing the fuel tank. If that happens, you'll get a fuel-starvation situation. DO check this, because if you ignore it, aside from making the bike run crappy, it'll eventually ruin the fuel pump due to cavitation. Don't ask how I know that.
 
I'll check/replace the plugs. It's a 2008, but was bought from dealer in 2010 and only use premium fuel, so not that bad. Doesn't sound like a kinking issue, I would think the problem would be more frequent if it were. But the plug and injector cleaning sound plausible. Will check filters too.

Thx for the tips, the impression I get is there is not an immediate sign of anything major, just keep up good maint.
 
might want to put in a iridium plug also....will burn a incorrect air/fuel mixture better than a copper one.
 
Dunno these bikes at all but any chance yer hitting the rev limiter?
 
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