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99 250
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My bike, after sitting for almost a year, would not get full power under full throttle  

First gear wasnt as noticable, but anything beyond that it seemed like it was choking on itself. Almost like a lope on a muscle car. 

 

I pulled the carb out, and I have a question about the accelerator pump thingy. The part that comes up into the intake looks like the tip of a ball point pen. Is that under some spring pressure and should be moving up and down? It looks like there might be some sort of corrosion on it, but its hard  to tell. 

 

I am NOT a gear head, so this is new to me, and any help would be greatly appreciated. 

 



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Hi there!

The accelerator pump nozzle is fixed in the carb body and, if working correctly, should squirt a jet of fuel into the carb when the throttle is opened.

If you are new to the TTR carb then it's worth looking here where you will find lots more info wink

Brian



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Your nozzle definitely looks covered in crud, but will probably clean up ok, and the most important bit is that fuel squirts through when the throttle is blipped. (I THINK you can check this off the bike by filling the float bowl with fuel and twisting the throttle linkage, but I'm not 100% sure) As Brian says, it should be a tight fit, not wobbly.

The accelerator pump only has an effect when the throttle is twisted, not at a fixed position, so if you're experiencing power loss I would look closely at the main jet. Judging by the deposits in the carb I would suggest it needs a darn good clean throughout.

I think there should be a banner across the top of the home page of this site saying "drain your carb if you're leaving the bike standing" It's not just TTRs, but they're notorious for blocked jets from old fuel.



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mossproof wrote:

I think there should be a banner across the top of the home page of this site saying "drain your carb if you're leaving the bike standing" It's not just TTRs, but they're notorious for blocked jets from old fuel.


Good point well made but, sadly, the people that most need to hear that advice almost certainly aren't forum members cry



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mossproof wrote:

Your nozzle definitely looks covered in crud, but will probably clean up ok, and the most important bit is that fuel squirts through when the throttle is blipped. (I THINK you can check this off the bike by filling the float bowl with fuel and twisting the throttle linkage, but I'm not 100% sure) 


Yes - you can check it off the bike but, if you are clumsy like me, you might spill a bit of fuel!

I am trying to sort out a fuel starvation problem on a leaf blower at the moment and have managed to spill fuel on the floor, on me, and even managed to get a mouthful - yuk disbelief

Brian

PS The problem with the leaf blower was a blocked breather in the fuel cap - the TTR can suffer the same - so engines is engines eh? 



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