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XT125x misfires a lot and will not idle.


Agibson3hr2
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I seem to be having a lot of issues with my bike such as misfiring when I'm throttling the bike and even after being sat for 5 minutes with the choke on the bike still will not idle when the choke is released.

http://www.youtube.com/watch?v=hp91D4DgS9k&feature=youtu.be

And it will not start when on the side stand either :\

Edited by Agibson3hr2
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Hi there mate, there are actually alot of bikes on the road that will not idle, mine for example! lol

Its almost certainly the carb that needs a clean and adjusting, i have tried but can never quite get it right!

I will have to soon though as i'm planning on getting rid of it.

So yeah carb cleaning/adjusting is my bet

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Hi there mate, there are actually alot of bikes on the road that will not idle, mine for example! lol

Its almost certainly the carb that needs a clean and adjusting, i have tried but can never quite get it right!

I will have to soon though as i'm planning on getting rid of it.

So yeah carb cleaning/adjusting is my bet

Yeah, I've taken my whole carb to pieces and cleaned it out, but tbh.. nothing seems to be working... when I turn the revs up on my carb it will idle nicely but as soon as I've been riding round town for say 20 minutes and stop... my bike is then idling at like 2000 revs instead of say 1200-1400 I have no idea what to do, it's annoying me and I'm thinking about getting rid of it and getting another bike.

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I'm thinking about getting rid of it and getting another bike.

They are pretty nice bikes, cheap on fuel, pretty light-ish, looks good, nice sitting position and seat but there is always maintenance or bits and pieces that need doing.......i guess every bike has things break from time to time but the problem i think with the XT is that people buy them as reliable commuting bikes and people expect not to have to do much work on them but you do, when it's something you can't do yourself garages take the piss with the prices they charge so people get annoyed and look for something else.

But lets be honest as far as bikes go the XT is pretty good reliable bike. You certainly could have picked a much higher maintenance bike thats for sure!

but yeah i'm not sure what to suggest mate, best of luck!

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They are pretty nice bikes, cheap on fuel, pretty light-ish, looks good, nice sitting position and seat but there is always maintenance or bits and pieces that need doing.......i guess every bike has things break from time to time but the problem i think with the XT is that people buy them as reliable commuting bikes and people expect not to have to do much work on them but you do, when it's something you can't do yourself garages take the piss with the prices they charge so people get annoyed and look for something else.

But lets be honest as far as bikes go the XT is pretty good reliable bike. You certainly could have picked a much higher maintenance bike thats for sure!

but yeah i'm not sure what to suggest mate, best of luck!

Yeah that's true, but I could put up with doing the maintenance myself if I were doing silly speeds to cause the bike to break in the first place, but with my XT I'm literally going to college and back every day and that's it... It's annoying me how a few of my friends thrash the s*%t out of their 2 strokes such as the RS125 etc and nothing has gone wrong with them but I can't get above 65mph and I treat my bike like royalty and it's breaking haha. I dunno, I love the bike but its just frustrating y'know? :P

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Actually on further thought! maybe the carb needs to now be set at a different level then the book says to make up for the big bore exhaust.

There is a lad on here 'prichard xt' he seems to know a heck of a lot about these bikes, see if you can contact him, he's on my friends list. Don't forget to post a comment when you get to the bottom of it so that others can :)

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Yeah that's true, but I could put up with doing the maintenance myself if I were doing silly speeds to cause the bike to break in the first place, but with my XT I'm literally going to college and back every day and that's it... It's annoying me how a few of my friends thrash the s*%t out of their 2 strokes such as the RS125 etc and nothing has gone wrong with them but I can't get above 65mph and I treat my bike like royalty and it's breaking haha. I dunno, I love the bike but its just frustrating y'know? :P

I understand matey! i'm sure theirs does break they just don't say anything ;)

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well that dosent sound right :)

have you changed anything else on the bike

air box, carb main jet, removed AIS, spark plug

or made any adjustment to

idle screw, fuel mixture sxrew

seems like a mixture problem

also is it a full system or just end can

hows the fitting between the can

downpipe and engine this could be an air leak

I use an over sized tail pipe which every 500 mile

the connection between the upsizer to down pipe degrades and lets an air leak

and back fires like fuck soon to be welded tho

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well that dosent sound right :)

have you changed anything else on the bike

air box, carb main jet, removed AIS, spark plug

or made any adjustment to

idle screw, fuel mixture sxrew

seems like a mixture problem

also is it a full system or just end can

hows the fitting between the can

downpipe and engine this could be an air leak

I use an over sized tail pipe which every 500 mile

the connection between the upsizer to down pipe degrades and lets an air leak

and back fires like fuck soon to be welded tho

well that dosent sound right :)

have you changed anything else on the bike

air box, carb main jet, removed AIS, spark plug

or made any adjustment to

idle screw, fuel mixture sxrew

seems like a mixture problem

also is it a full system or just end can

hows the fitting between the can

downpipe and engine this could be an air leak

I use an over sized tail pipe which every 500 mile

the connection between the upsizer to down pipe degrades and lets an air leak

and back fires like fuck soon to be welded tho

I haven't changed any of the above and it is a full spring loaded system.

I'm not too sure where the idle screw is exactly on my carb and where the mixture screw is... It was to my understanding that the idle screw was on the left hand side.

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My idle speed was all over the place! I've sorted all the idle speed/mixture out, you may need to adjust your cam timing, that helped mine loads! And its pretty easy to do just takes a bit of time and a couple of tools.

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Alex Do you mean adjust the cam chain tension? Not timing? the cam chain if loose will mess with timing but to my knowlage the cam timing is fixed and not adjustabl unless you slot the sprocket mounting holes and index the cam using a degree wheel.

Personaly I think you need to check the valve clearence.

Then if thats ok then set the carb up

set float height to factory spec.

fuel mix screw at 1.5-2 turns from fully seated,once you have the bike ideling again you can keep adjusting for off idle performance IE no bog when snaping the throttle open. But only go 1/8of a turn at a time

Also not starting on side stand will it start standing upright with side stand down? if not you have a problem with the side stand saftey switch could be cutting out your spark then when it allows spark you firing raw fuel which could back fire in the pipe. And realy mess with the back pressur in the cylinder.And stop your bike from idleing.

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Have you richened the mixture for the pipe?

Anything else non stock.

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iv had recent back firing an it was due to the hose from fuel vac to manifold being kinked and perished

I this will sound abit of a novice but could you change the value timing by

turning crank to TDC

take the cam covers off

remove tensioner

and rotate the cam side chain gear by

1 tooth or however many times either way

keeping the chain in the same place (use markings)

then fit back together

not the most technical but you get the idea

I may try it before I change engine

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and what did you set it to if you don't mind me asking

stock intake valve is 0.08 closed

stock exhaust valve is 0.12 closed

im going to spend some time tomoro

messing and tweeking to get her running better

so this would be helpful

I assumed you had to change the cam

to get the valves to a lift higher

or is there limit on the free play

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