I'm new to motorcycles and have purchased a 2nd hand ZXR250c 1992. I've been having some issues with getting it started and just have some questions. So basically its really cold where i live right now and i have to start the bike with full choke in neutral when its cold, it starts first time. but when my bike has been warmed up it will not start in neutral at all(even with choke on) but in first gear it will start first time, is this normal? if not why would it be doing this? so basically when its cold i have to use full choke in neutral to get started and after its warmed up i can only get it to start in first gear.
I'm at a loss, the correct starting procedure is to have the bike in neutral, full choke, no throttle then press the button. Once the engine has warmed up, you shouldn't need any choke, by putting the bike in first, means you have to have the clutch in and the side stand up to allow the starter circuit to work.... that's very weird indeed
yeah so starting the bike up cold its pretty standard procedure but after it has been warmed up, if try start it in neutral i can hear it trying to start but it won't quite catch, but if i shift into first gear it will start fine. I've never riden another bike before so i have no idea if this is just how it is. if its not normal would anyone know why its doing this?
hrm, if it was simply not starting while warm i would assume its flooding.... but the first gear thing is queer as...
The only thing I can think of is the thermostat... when its heated it cuts out something somewhere... Maybe a bit of a long shot but it could also be a fuel tap thing. Extra fuel flow when cold is encouraged, as it helps the bike to start. Not so much when the bike is hot, it will flood. Not that i've seen a wiring diagram for your bike or anything though. It is a bit strange.
Well, talk about being confused??? Cold, with choke on the bike starts fine. After it has warmed up to operating temp it won't start unless it is in gear???????????????? This makes no sense at all.. Ok, it has started in first gear? secondly when you have started it in gear and put it back in neutral,what happens? Have you tried starting in any other gear?? Sorry about the ????? but this has me scratching my head
Have you tried a tiny amount of throttle no choke in neutral when warm starting? It actually socks in more air
Hey Stu, The thermostat is mechanical so it couldn't interfere with the electrical system... I'm wondering if its more that carbs \ petcock that need a tickle. Rose what would happen if you had the bike in neutral while it warmed up, stress the starter a give it a tiny bit of throttle ( not too much) , my old ZXR250 would start fine when cold with the choke, but I either had to give it choke or give it a bit of gas if I had to start it when it was warmed up. It ended up being a failed seal in my carbs, once that was replaced the bike started fine when hot. My advice is carefully check the plumbing around your carbs, next step would be a Litetek seal kit The starting in first gear thing has me perplexed Cheers Chris
After starting the bike warm in first gear i can put it back into neutral fine. I have not tried starting it in any other gear but I will give it a try next time to see what happens. I have tried every combination of throttle and choke whilst in neutral when warm but it just won't catch.
Have you tried starting it in neutral when warm whilst pulling the clutch lever in ? I wonder if it's a faulty gear position switch or (less likely) a side stand switch.
I thought the same to start with, however I dismissed this as cold it starts fine in neutral with choke on. Sure there is a reason, I just can't find it!
Hmm. I was thinking about this today and have a couple more ideas. Try looking at the fuel line(s). On older bikes (due to the age of some things) they can become a bit thin and may warp when hot, which will throttle the fuel flow meaning you're not able to get enough to start. The other thing is the electrical connections. I'd start with the spark plugs, take all the leads up and have a good look at them, and push them back on tightly. Also ensure that the leads are screwed into the heads correctly. What may be happening is some kind of thermal expansion when warm which separates the connections somewhere causing you issues. It doesn't exactly explain why it only happens when starting because technically this would also happen when running. But perhaps when running there is already enough current for a spark to bridge whatever gap is there, but when cranking this may not be the case. Not sure on the gear thing though, starter clutch? Dunno.
I don't think it can be fuel as the bike starts with it in gear. I am inclined to look towards a bad earth connection as the bike may be earthing through the neutral wire when hot and need the extra power for spark when cranking. Suggest you run a multi meter over the earth connections and through the clutch switch as well as the neutral switch.
