Team-BHP - Motorcycle randomly fails to start

Quote:

Originally Posted by SatheeshBHP (Post 5647984)

I think it is due to Engine temperature. Hotter the engine, difficult to start. I also noticed engine tends to stall randomly when idling at hot temperatures. Once on a very hot day, after heavy traffic, engine failed to start for more than 10 mins, So I poured 1 little cold water on the engine and it immediately started in single crank. :Cheering:

But wouldn't pouring cold water be a drastic temperature change on such a hot temperature for the engine block? I have only had the starting issue, no turning off at hot temperatures or anything. It stalls sometimes due to random hiccups but it's very rare.

Quote:

Originally Posted by Gautam_707 (Post 5648622)

Yes, Sharp temp change is not good for engine. But after 10 mins, I thought temperature would have dropped enough to not to cause issues. I was thinking that hot engine should not be affected by splashing cold water (may be like a puddle water splashing?). Honestly I was in a hurry so didn't think much about consequences at that time.:uncontrol

For me also stalling is very rare but happens only in hot engine.

May be we should try with non ethanol petrol (power/premium petrol?) and check if we still have the problem.

I'm now afraid to turn off the engine in signals because it might not again for some time :Frustrati

Quote:

Originally Posted by SatheeshBHP (Post 5648683)

May be we should try with non ethanol petrol (power/premium petrol?) and check if we still have the problem.

I'm now afraid to turn off the engine in signals because it might not again for some time :Frustrati

Not really sure if the higher octane fuel or premium petrol would make such a big difference, especially since our engine is pretty low in compression. It's one of the many, many reasons I picked the fzs25 too, because that just means better reliability. I sometimes worry at the signals as well but since it doesn't take more than 2 minutes at most, it usually starts up fine. The coin rattling sound drastically gets louder when the engine is hot though.

Quote:

Originally Posted by SkylineGTR (Post 5633733)

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).

I own a 2019 FZ25 BS4 and I have been facing the same issue since day1. However, your injector theory seems true and it seems this is by design and not a bug. The reason I say so is because of a video I watched of YouTuber Life of Pal where he claims a Yamaha service advisor / mechanic said this to him. Sharing the link here. Worth taking a look.

https://youtu.be/N-synYK-j4M?si=6aszF447uliAVOx3