Hi, my wife has a xr125 which she is using to get her confidence up before going for her big bike license.

2 weeks back I was informed that the bike was going like a dog.....it would start but was behaving peculiarly when accelerating - it appeared the choke was on.
A week later it appears that the bike is behaving in a similar fashion (x1000), but the choke isnt on this time.

- The bike starts fine.
- The bike revs fine in neutral.
- In gear, the bike will not accelerate beyond a dawdle before wanting to stall, followed by stalling if you deccelerate immediately - it has the same feel as driving with the choke on but exaggerated.

Any advice would be appreciated, Id like to try fix this myself so may ask plenty more questions.

Thanks

Gotta check fuel flow - disconnect pipe from tap - and run into a jar to see is flowing nice for at least 10 secs +, & check filler cap breather hole by undoing cap whilst draining fuel into jar (does it flow quicker with cap off?) .

If OK - drain carb and check for shite

Is air filter clear ????

Take plug out & check colour (post photo if not sure wot you're looking at.

Awesome, sorry for delayed replying.

I will give this a go this evening, wanting to pick up some carb cleaner and a new plug.

The exhaust is blowing a bit and has gotten a bit worse - could this be the problem ?

A leaking exhaust will effect the running - but probably only marginally

Pigford......I think I need help.

1. I disconnected fuel line between tap and carb, fuel flowed well.
2. Opened petrol tank cap and fuel flow did not alter - no blockages.
3. Carb...well, that is now in my kitchen. Removed Float chamber and there appears to be some (tiny amount) fine black powdery stuff at the bottom. I have drained this.
4. Air filter...looks a mess to me (as attached). Was planning to get a new one tomorrow and fit. Is it ok to use clean engine oil on the filter ?
5. Spark plug....another mess...as attached (Black, powdery, gungy..not wet).
6. I didnt check compression, but replaced the plug and shocked myself while testing....wow, the current can jump to earth itself.



A few question to questions....
1. Can one use a general degreaser to clean the carb, in addition to carb cleaner ? (how would one clean a carb?) - I read one can boil a carb in lemon juice (dont laugh). Why should one not use water to clean a carb, assuming it is dry before refitting ?
2. How do I remove the throttle valve slider from the bike ? - Do I need to take the entire throttle cable off ?
3. I notice on the choke there are 3 settings...the butterfly is full open, partially open...and closed ??
4. The obvious question....what next to get the bike run ?

PLENTY more questions to come.....hope that is ok.

Im going to nose around a bit and check of the jets are clear....

Thanks for the help.

Attached Thumbnails

 

 

That plug is BLACK.. Althogh , with a filter that old and clogged, im not surprised lol..

It could also be that black from the choke sticking or you're burning oil. Checked the level ??

Anyway, while the carb is in pieces, make sure the float bowl valve doesnt have a fine filter hiding under it. These often get wet.

It's a shame you took the carb off before checking the fuel flows from the carb drain freely too.

Anyway. Dont use degreaser on your carb. It leaves a residue. You can use petrol, or carb/parts/brake cleaner.

Blow out ALL the jets while your in there.

Take the top of the carb off and check there are no holes in the diaphram. Thats how you get the slider out too. BE VERY CAREFUL not to lose any parts and be very systematic taking it apart. Keep things in order.

The choke has three settings. Its nothing complicated or fragile. You will be able to see it open and close now the carb is off.

__________________
Did some trips.
Rode some bikes.
Fix them for a living.
Can't say anymore.

That looks like a paper air filter. You're not supposed to oil those, just use them as they are. Oiling a paper filter will clog up the pores in the paper, restricting the air flow and causing the problems you've mentioned.

Only use oil if the filter is made of foam. The holes are much larger so the walls can be coated in oil and still allow air to pass through.