Facing random starting issues with my 8 month old Yamaha FZ25

It never happens in the morning when I start the bike to go to work.

BHPian SkylineGTR recently shared this with other enthusiasts.

I have a Yamaha FZ25 BS6 model, bought 8 months ago. I have a rather strange issue with the bike: it will randomly fail to start on some occasions, behaving as if it has run out of fuel. I will have to crank it 4 to 5 times in order to start the engine, sometimes by giving it some throttle (which is bad for FI vehicles)

The issue happens completely randomly so far however I have noticed some patterns:

• It never happens in the morning when I start the bike to go to work.
• It mostly happens when the bike is started a short time after turning it off. Say I get home from the gym, park it, then 20 minutes later I have to go out, so I start it again; and it refuses to start.
• Many a times this happened when the bike was parked in direct sunlight. I have a theory that the sun is causing the injectors to heat up and making the petrol inside them evaporate, requiring extra fuel when starting again. Cranking it 4-5 times provides this extra fuel which allows it to start. Don't know if this theory is technically sound though. Another reason I am not sure about this theory is because it has sometimes happens in evenings too, after sunset.
• Everytime this happened, the bike was parked on a side stand. I initially thought it had something to do with the side stand kill switch but the SVC said it was all good.

Its not a major issue, but it is still annoying to have a new machine behave unpredictably. You expect starting trouble on machines with carburetors, not FI ones.

Any advice is appreciated, thanks in advance.

Here's what BHPian Balaji31582 had to say on the matter:

 It happened to my FZS25 also. I was told that we need to maintain certain fuel level as sometimes when we have the bike with side stand it could eventually take little more seconds to regulate the fuel flow. I also have a main stand added to my bike. I also tried using main stand but still had this issue. I am not 100 percent sure about this theory. But once I start maintaining the fuel level with minimum 2 bars, I haven't face this.

Here's what BHPian windrider had to say on the matter:

Get the fuel lines checked for small leaks or blockages. Also get the injectors and fuel pump checked since you say the bike is behaving like it is not getting fuel. If these three systems are fine, ask the service centre to check for any electrical issues. I had similar experiences with an old Suzuki gs150 and my own BS3 unicorn and the culprit was a faulty CDI unit in both cases. They would run fine most times and out of nowhere start behaving strangely. Sometimes they would turn off as if starved for fuel and refuse to start. Then after 5 minutes would turn on as if nothing happened Mind you, the bikes were already around 8 or 9 yrs old at that time, so I don't know if this issue can arise in such a new bike. Could also be due to fouled spark plugs.

Here's what BHPian RD150 had to say on the matter:

Hey, faced the same issue with my R15 long time back.

Please check if:

• Fuel pump is ok
• If there's water in fuel tank
• If injectors are ok

Here's what BHPian Baristyro had to say on the matter:

• Maintain a chunk of fuel, basically 2-3 litres of pseudo-fuel capacity one shouldn't ever use, lest you cook your fuel pump
• Contend with an inaccurate digital fuel-level indicator
• Protect the fuel pump like an infant, from the heat, from the water, from itself!
• Clean the throttle body every so so kms
• Shoddy self-starter motors, along with no kick start to start with...
• Connectivity features that may randomly drain the battery
• Fragile ECUs about which regular mechanics know jackshit, replacement is guaranteed a 5-figure slap to the pocket

Why are these BS6 bikes such wussies?! How did we come from an era where some bikes used to function completely normally without any battery, or without any fuel in the tank(fuel in the carburetor), to these dark times where one risks catastrophic failures by using all the fuel that they pay for. A double whammy for someone who lives paycheck to paycheck, for whom these two-wheelers are supposed to be a necessary means of transport.

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