Engine dies above rpm 7500 also idling problem, YBR250

[modron]

Hello,

I have a bit of a problem with my Yamaha YBR250. Engine dies above rpm 7500-8000, at the beginning I thought it looses power but today I found out that it actually dies. First time it happened I shifted down to 4th and it went on again. I was 200km away from home so After the same thing happened 2-3 times i decided to ride slower (had some idling problems at the end too) and the next day I took her to my mechanic. I explained the problem and also told him that when I start it cold it idles at around 1000-1200 a bit lower then the manual says, after 10 min it goes down to around 800 and after 15-20min it stalls at every gear whenever Id let the revs drop so low (very annoying), he said that he needs to keep the bike overnight and ride it to check. 4h later he called me and said that he thinks he fixed it but cant be sure about the high rpms cos there are no roads in the city to ride bike so fast. The idling was 1300-1500 (as in manual) when cold and 750 when hot (stalls occasionally). Few days later I went out to ride and at the first stretch the engine died at about rpm 8000. When engine died I puled the clutch and stopped the bike, when I tries to start it it wouldnt. I had to turn the ignition key to off and on again to start. I took it back to the mechanic and he fiddled with it for few hours then he said it should be fine. He also told me its because I ride it too much, meaning too long in one day. I cant see how this is relevant, I usually stop every 1,5-2h for a short 10 min brake.

Today I took it out and everything was fine for first 3-4 hours (apart from idling- still ok when cold and much lower when hot) after the problem came back. It seems like the EFI cuts off fuel at high revs...but its just my guess. Im not sure if the mechanic tells me the truth cos the bike is still on warranty for next 2 months and if EFI is broken they will have to replace it

Do you guys have any idea what this might be

greets

[zhu]

Fuel pump an / or Fuel filter
would be my guess

[modron]

ok, thanks. Is there any way to check if its all got for a person with minimum knowledge? i would be happy to have a look but I dont know what should I be looking for. How to check if they are faulty? I will do some googling

[zhu]

yep connect it to a computer and it will give you an error code , this error code may be translatd to English and corrected by the application of money.

welcome to EFI

[marcrbeaudry]

a quick 'limited knowledge' check you can do on your own is to carefully inspect all your vacuum hoses-
starting from the breather in the tank , and also the injection rail - make sure there aren't any dangling hoses, or
connections that are without a hose or cap. make sure all the hoses are in good shape -not dried out and cracked (subsequently - leaking)
beyond that - with limited knowledge and tools - you don't have many options other than to get it into someone who
can diagnose it for you properly.

[marcrbeaudry]

Sorry - i missed that it's a NEW bike - you shouldn't have cracked hoses - but possibly an assembly issue with forgetting a hose - if it's on warranty ( i also missed that - sorry) - bring it back and tell them you intend to bring it back to them everyday, every single day until it's right. Riding it 'too much' is simply bullshit and non-acceptable as an excuse. Ask the mechanic to show you in the sales brochure or owner's manual where it says you cant ride it more than a few hours per day... anyone telling you that shouldn't be selling or repairing motorcycles.

good luck
marc

[modron]

I dont think its due to some issues with the hoses. If it was an easy fix they probably would have fixed it the first time I brought them the bike.
Anyway, Im waiting for the parts now. Should be few day. Ive inquired about the warranty and apparently its Yamaha warranty not shop warranty which is way better cos they dont need to pay for new parts so I hope they will get what is needed ;) fingers crossed