Gen 1 Wont start hot

elquefaltaba1

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Hello!
I posted my problem on the Newbies forum but maybe its better to post it here, any kind of advice would be appreciated.
Im a proud owner of a 2000 Hayabusa and obviously... having problems to start the bike when its hot.
The bike is 100% stock and the odometer reads just right. The bike starts like a champ when its cold, no problems at all. Once its hot, if I let it off for around 20 min then It wont start until 2 hours later when it is cold again. Everything sounds good but it just feels like its not getting fuel.
I tried changing Plugs, battery, starter, temp sensor, radiator additive... it didnt make a difference.
I cleaned fuel filters and replaced the pump for a Bosch 69420. The fuel lines look good. If they were getting kinked I assume the bike would have trouble starting neither hot and cold? When I ride it everything feels fine.
I tried to cover everything with heat insulation material since I read heat could be an issue. Maybe it helped a little... but Im not sure.
If the bike its hot and doesnt start, I tried to start it by opening the gas tank but it didnt help.
Lately I found out that once I switch the ignition on, when the bike its hot, I can listen to the pump working and a lot of bubbles... during 5 secs. Or that is what I believe, after so many tries Im getting crazy. I think the problem is vapor lock caused by the heat, I just dont know how to solve the problem.
Thanks a lot for your help.

dadofthree

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You could try engine ice but more than likely you’ll end up adding a second fan or G2 setup on the bike. The water pump could be the issue or the radiator cap. Best of luck. Experts will be along soon.

dadofthree

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Vapor lock was a problem with the out of tank fuel pumps. An old trick I remember is putting a beer cuzzy around the pump. There’s a butt load of threads on these issues.

Peter1127

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I have a 2003 model with nasty fairing and bought a 2002 mint set including gastank. Didnt want to do the external fuel pump downgrade so decided to modify it using the whole interface. No worries about the pump anymore. Purist probably wont like it but it works.

tank2.jpg


tank1.jpg
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