MC19 Failing to Rev

[Brevin]

Hi Guys, i'm a bit of a lurker on these forums but now it's time to ask for some advice.
I bought a MC19 CBR250R a year back, and the motor was getting tired so the previous owner replaced it with a MC22 (CBR250RR) motor. Now some custom wiring had to be done but up until now it's run mint.
Coming down the mway this morning my bike started to cut out... knew it wouldn't be petrol so i put the hammer down. The bike started to feel like it was running on three cylinders, and sounding similar to and if i put the hammer down it felt like i was drowning it, and when i came off the throttle it'd run right.
I've just recently had it serviced, changed the plugs etc. and now this is happening.

I'm freaking out cause i don't want it to be something major and unfixable cause my bike is my freedom!!

[breakaway]

If the problem started suddenly, then could it be because crap got sucked into the Carbs? Maybe water in there?

I had similar problems, my bike had been sat for ages and the carbs were WAY out of sync when I got it. It struggled to idle, but changing the plugs + synching the carbs made a world of difference. Gonna run a few tanks of "carb clean" through it as well (You buy it a the bike shop and mix in like 40ml of it with your petrol (there is a proper mixing ratio), and it cleans the crap out of your carbs - unblocks the jets etc)

[babyblade250rr]

Hi Guys, i'm a bit of a lurker on these forums but now it's time to ask for some advice.
I bought a MC19 CBR250R a year back, and the motor was getting tired so the previous owner replaced it with a MC22 (CBR250RR) motor. Now some custom wiring had to be done but up until now it's run mint.
Coming down the mway this morning my bike started to cut out... knew it wouldn't be petrol so i put the hammer down. The bike started to feel like it was running on three cylinders, and sounding similar to and if i put the hammer down it felt like i was drowning it, and when i came off the throttle it'd run right.
I've just recently had it serviced, changed the plugs etc. and now this is happening.

I'm freaking out cause i don't want it to be something major and unfixable cause my bike is my freedom!!

there's also a possiblity of a faulty plug? or perhaps gap setting in one of the plugs? who serviced your bike maybe something they did wrong, another possibility is when the leads were put back on one wasnt on properly and worked its way loose

[Brevin]

If the problem started suddenly, then could it be because crap got sucked into the Carbs? Maybe water in there?

I had similar problems, my bike had been sat for ages and the carbs were WAY out of sync when I got it. It struggled to idle, but changing the plugs + synching the carbs made a world of difference. Gonna run a few tanks of "carb clean" through it as well (You buy it a the bike shop and mix in like 40ml of it with your petrol (there is a proper mixing ratio), and it cleans the crap out of your carbs - unblocks the jets etc)

In regards to this Carb Clean... is it the same stuff you'd buy from repco or anything? Because i phoned around and can't find any that stocks it for motorbikes... perhaps you could give me a contact number of someone who i can get it off?

[babyblade250rr]

In regards to this Carb Clean... is it the same stuff you'd buy from repco or anything? Because i phoned around and can't find any that stocks it for motorbikes... perhaps you could give me a contact number of someone who i can get it off?

same as the car stuff dude just make sure you get the ratio correct or you foul your new spark plugs

[breakaway]

I'm not sure if it's the same as the car stuff, but I was told Mt Eden Mc has it. I would go in and have a look. Get the Fuchs one, it's good shit. I need some myself.

[Brevin]

Cheers guys, your guys are awesome... will go and try that nowish and will let you know how it runs

[jim.cox]

A copuple of thoughts...

How long has it been since the air-filter(s) was(were) cleaned?

Maybe water in the fuel tank - it can be hard to eliminate as the petrol floats on top. Suggest you drain the tank completely - just adding fresh fuel will not fix this problem

.

[Ragingrob]

Check out my thread in the electrical forum, my CBR's done a similar thing recently and I think we've narrowed it down to the regulator ...

When it's cut out has the dash and all cut out too?

[hurricane_r]

hey mate, long time no see,

im "the guy" who sold u your mc19, good to see it went hard for a year,

i know that bike top to bottom so run through these

spluttering = try ur fuel pump, they eventualy die and mc19s have em mc22's dont, make sure no wiring has come loose, try to hard wire it to see if it is working,

pull your plugs, inspect them make sure they all look the same, and arnt fouled,

re-inspect the clutch earth i made on the handle bars, to by-pass the microswitch

full taps on mc19's can sometimes break make sure ur tank still dumps gas !

sounds like simple prob , pm me ur address and i can come have a look

anyway we should go for a ride sometime, let me have a spin on my old sensei
good luck !