Idle-Twist Throttle-Choking

[benzina]

I have a problem,that has progressively got more frequent,and worse, over the last couple of weeks,to the point now that i am unable to use the bike at all.
The problem is when the bike is at idle,and then i go to twist the throttle to accelerate,it just chokes & fouls,and the revs actually drop down from the idle 2000rpm till i release,then it's back to idle,then again it chokes downward on the next twist,and through it all,i get no movement at all.
During most of these episodes,with some throttle manipulation and luck,i have managed to get the revs to splutter upwards of the idle mark,and back into life,where it has enabled me to take off and run and perform as normal,but then again at times when i release the throttle to slow right down,and then twist to accelerate,the same problem occurs,and so i'm stopped and having to deal with this problem.
Now even the idling is slightly rough and inconsistant,where as before,that part was o.k.
I have pulled the plug,and found it completely dry black,telling me that it's far to rich. I put a new plug in anyway,and started it,and just listened,to which it then started to idle slightly inconsistant and rough,and the same twist to go,but it just chokes down badly,and no go.
I am going to truck it to my dealer who is 30km's away on Tuesday,where he tells me he's going to put the diagnostic device on it to see if it tells him anything.
Thinking back,i do remember i had some kind of oil leak or spill, about a week before this all started. I noticed my center stand,and behind the transmission casing had blackish oil on them,and a couple of drops on the ground. I checked to see if i could find where it came from but could'nt,and the engine looks clean.
Could it be the air compressor? or the air injector? i don't know, this is beyond me,but that spark plug looks like it's either getting to much fuel,or not enough air.
Perhaps someone knows these symptoms from my descriptions,and can hopefully pinpoint the cause of this problem,so i can take this to my dealer as a back-up,and cross-reference for his analysis.
This is the first time it's ever let me down,and i have a feeling it's got something to do with one of two things that i have changed to my feeding formula just recently,and that is using 98ron fuel instead of 95,and the other is using Agip Cross 2T oil,instead of my trusted Castrol TTS.
One thing for sure,when we find what the problem is,i'll be going back to feeding it my original fuel and oil.
I really miss riding it,and am slighly annoyed,as it's been great weather,but i'm philosophical about it,and just look at the big picture,which always puts things into perspective.
Reply's much appreciated & thanks in advance.

[muchacho]

Does the bike make any popping noises when you accelerate? Have you seen any fire come out of the exhaust system? If you rev the bike slowly and build up speed, can you then increase the RPMs (slowly)?

Have you cleaned the injector?

Have you checked to see that the exhaust system does not have leaks where it connect to the engine? Is there anything inside it obstructing passage? Have any part of the it' system become loose?

I would concentrate on the exhaust system for the moment.

[Ciudale]

Sludge prob ?

[benzina]

Does the bike make any popping noises when you accelerate? Have you seen any fire come out of the exhaust system? If you rev the bike slowly and build up speed, can you then increase the RPMs (slowly)?

Have you cleaned the injector?

Have you checked to see that the exhaust system does not have leaks where it connect to the engine? Is there anything inside it obstructing passage? Have any part of the it' system become loose?

I would concentrate on the exhaust system for the moment.

#The popping noises were evident when trying to rev upwards to accelerate,yes.
#I have'nt seen any fire from the exhaust.
#Increasing the revs very slowly,has been my technique in getting the revs to go up,and not down,and when it has worked,i have managed to make it struggle up to about 4000-5000rpm,where it takes off,and so do i,as i quickly get it off the stand.
#The bike has covered 11000kms,and i have never had the injector cleaned.
#The exhaust system does not have any leaks as far as i am aware,but i will have them completely check that tomorrow.

[muchacho]

are you able to get the bike up to any RPM (maybe 6500) if you do the slow acceleration method AND you are on the bike?

sound like the sludge issue ha cropped up, but it is strange that changing the plug had no effect.

[benzina]

When i had got it going,whether on the stand or not,it would rev past all the fouling and go up to normal 8500-9000rpm's,and all operates as if nothing is wrong,for a while at least till the next episode.These episodes became more frequent,and the symtoms became worse over the last two weeks. I found having it on the stand when i had this issue, gave me the best chance of getting the revs up,without my weight being a factor.
Yeah,the new plug failed first off,and i gave up after the first minute of trying to get the revs up, knowing that it's now got pretty serious,and even if i did get going,i'm sure i would'nt make it back.So i just switched off,and have'nt started it since. I did pull that plug to have a look at what a few minutes of idling,and trying to go,did to a brand new plug,and it was all black. Perhaps it's not getting the required air it needs in getting the air/fuel balance right,so i'm thinking on those lines.

[Ciudale]

Like on the Morinis there an injection pressure regulator (the infamous "bowl") on the bike, so you should open it and check for over-sludging. Then like you said, a leak or something wrong with pressure/fuel delivery. But the symptoms you are talking about (bike revving on the stand, not when loaded) remind me sludge issues...

[muchacho]

Try this:

Take out the plug and leave it overnight (or equivalent), then put in a new plug and see if it gets better.

I suppose it will only be temporary, better check for sludge in the injector.

[benzina]

Like on the Morinis there an injection pressure regulator (the infamous "bowl") on the bike, so you should open it and check for over-sludging. Then like you said, a leak or something wrong with pressure/fuel delivery. But the symptoms you are talking about (bike revving on the stand, not when loaded) remind me sludge issues...

Where in fact is this injection pressure regulator,and what does it look like? Is it easy to open & check for sludge? If it's not easy,i will ask my mechanic to do it when i take it in tomorrow. Thanx

[tas111sat]

If you have the purejet engine same as mine then if you take out the battery and the thing the battery sits in and maybe the pieces either side of the battery you should be able to see the cylinder head which has a green thing on it. The presure regulator if thats what its called will be underneath it and back a bit facing down its a round black thing with 3 screws holding it on i checked mine and it had loads of white stuff in it.
Sorry if this isnt very clear but its the best way i can describe
Heres a picture the thing you are looking for is right next to the number 1 but item no.1 is the whole inlet valve. i dont think its the right scoot but the pressure reg is in the same place

http://apriliayorkshire.co.uk/catalo...jection%20unit

[benzina]

Thanks tas111sat, i had a quick look,and found exactly what you have described. Now,if i want to unscrew this pressure regulator to check for sludge,do i simply just unscrew it,or do i have to block anything before i unscrew it? Once unscrewed,whats the best method of removing sludge,should i find any?

[Ciudale]

Wait an hour that the pressure in the system goes down, then you can open it, just 3 torx to remove. Nothing more to know, except that if you have the plastic injection body the threads are fragile, so don't over-torque the screws when you put it back, 1-2 Nm is enough. Get a long torx key, easier to access the screws in that area.
If there is any, simply clean the sludge with paper and rince it with gas.

[benzina]

Thanks Ciudale, i'll see if i have time to have a look tomorrow morning,before they come to pick the bike up to take to the dealer,as it is late here now,and i've had a big day. One way or another,i'll post the outcome to all this.
Many thanks.

[Ciudale]

This is really nothing to do, this would be useful to check it before they touch the bike...

[muchacho]

Does this help you at all?