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Fizzeetoast

Joined:

Jul 12

Posts: 51

Fizzeetoast says:

Honda XR full throttle problem

When I apply full throttle on my XR125 my bike bogs down and seems to lose power and drive and won't accelerate properly at all. This happens in all gears I think and means I can hardly get the bike above 40 mph at the moment, would anyone be able to suggest what's going wrong here? Thanks a lot.

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  • Posted 2 years ago (02 November 2012 02:44)

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kcmc

Joined:

Jan 08

Posts: 7614

kcmc says:

Honda XR 125 Year ?

Hi Fizzeetoat

This can be a number of things causing that problem,most of the time its carburetor related,either poor carb fit causing a air leak,or poor adjustment of the carb itself,very often with an older bike it can also be water droplets in the carb float bowel which get sucked up onto the main jet at high R.P.M.s and(effectively cutting off the fuel)then drop off again as the rev's drop.It can also be the choke slide needle needs lifting a notch to allow more fuel at higher R.P.M.s,but the fitment and water and debris in the float bowel and fuel tank would need checking before advancing to carb tuning,also check the air filter,and the fitment of the air box rubber to the carb and air box and the intake duct while your at it.Good Luck

KCMC:tongue:

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ricklincs45

Joined:

Aug 05

Posts: 9

ricklincs45 says:

Carb

Try the points kcmc has suggested; if you need to check for water in the fuel, drain some off into a small container - if there's water in there you should be able to see it as it usually separates from petrol (will look like individual droplets).


If you don't do any good with those, you might want to start looking at the spark plug - your symptoms could also be part of the ignition system breaking down under heavy load.

I take it you are running with a proper air filter in place?

Rick

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Fizzeetoast

Joined:

Jul 12

Posts: 51

Fizzeetoast says:

The bike is 2005

I really appreciate your help and I'd love to know where to start but honestly a lot of what your saying is like a foreign language to me haha, I got my bike this week and it is my first bike, the most advanced thing i've done is changed the clutch and throttle play and lowered my idle speed :wacko: I can probably do some of these things but given my lack of experience do you think I would be better to take my bike in for a service otherwise which would you suggest I tried to tackle first?

Thanks.

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Fizzeetoast

Joined:

Jul 12

Posts: 51

Fizzeetoast says:

Running with choke on

About your earlier suggestion with regards to the choke maybe needing to be on a little bit - would it be safe and healthy for the bike if I actually left the choke ever so slightly or maybe half way on if it's not receiving enough fuel at high rpms because to me it does almost feel as though the engine is struggling to find power/fuel as soon as I go above 3/4 throttle.

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jaffa90

Joined:

Mar 09

Posts: 8945

jaffa90 says:

xr125

You look familiar,

http://www.motorcyclenews.com/MCN/community/Forums/Categories/Topic/?&topic-id=434563

A full choke will only take you to approx 3,000rpm,

Did you buy this bike as faulty?

It could be something simple or serious.

[This Reply has been modified by the Author]

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Fizzeetoast

Joined:

Jul 12

Posts: 51

Fizzeetoast says:

Faulty

No I didn't buy it as fault, the idle problem has been sorted out but i'm a bit more worried today as I have had a slightly more serious problem - instead of the bike bogging with full throttle today on the way home from work the bike bogged out while I was riding normally, I downshifted then went to blip the throttle and the throttle had no response then bike just bogged out and wouldn't start, eventually I got the bike to start I got like 20 meters down the street and it bogged out again. I couldn't get the bike to start for even longer and my electric start began making strange noises and wasn't hardly working at all, once again i got the bike to start running again and it was strangely perfect, was riding and running very smooth and I actually could use full throttle and it didn't bog at all - any help on this would be greatly appreciated and I really hope it isn't serious.

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jaffa90

Joined:

Mar 09

Posts: 8945

jaffa90 says:

bogged

It could be either the fuel/carb or electrical,if possible when it does it again, give it some throttle till it dies then  remove the spark plug to see if it`s dry or wet with petrol,note the dangers involved doing this.

Edit (plug)

[This Reply has been modified by the Author]

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Fizzeetoast

Joined:

Jul 12

Posts: 51

Fizzeetoast says:

fuel/carb/electrical

Right okay so I need to:


a: clean out the carb and jets

b: charge the battery (although I don't know how is best to do this)

and then finally with the fuel would it be a good idea to just brim the fuel tank and see if it kind of sorts itself out or what would be best to do?

one more note is when I received the bike the fuel tap was actually set to reserve so does that mean i've got 7 yearts worth of crap running through my engine?

Thanks a lot

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jaffa90

Joined:

Mar 09

Posts: 8945

jaffa90 says:

fuel

If your satisfied it`s a fuel problem then it could have a faulty fuel tap diaphragm (if fitted) it could be  rust inside the tank (metal i hope),it could crap in the carb partly blocking the jets on and off.

Battery,always use a bike battery charger.

I suggest you get a Haynes manual ,or use google.

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Fizzeetoast

Joined:

Jul 12

Posts: 51

Fizzeetoast says:

Diagnosing the problem

No I'm not suggesting it is definitely fuel related I literally have no idea what could be causing it, I was just hoping someone would be able to tell me after hearing the bike completely bogged out then actually started working better than normal straight after.


edit: after reading up a little bit to try and find the source of my problem I have one more thing to mention which I didn't realise could be significant, it was raining before it bogged out and my bike was out in it while I was at work.

[This Reply has been modified by the Author]

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