Odd one that smarter people can help me with — my father has a Royal Enfield twin. Solid bike; buzzes around town with it. He's put about 6,000 miles on it in the last couple years.
A few weeks ago, after being out large rainstorm, it had some trouble starting. It ran a bit rough, and then stalled out. It wouldn't restart. Starter and everything seemed fine, but wouldn't start. He asked me to take a look, so I went through the usual checklist. Sparks seem fine. Air filter seems fine.
I don't have a lot of experience w/ fuel injected bikes, but I pulled the tank off. Fuel pump seems OK. I can hear it priming when turning the key, and if I disconnect the tank, fuel sprays out. Then I yanked off the fuel injectors. They seemed fine as well — or at least, fuel sprayed out of them while starting the engine. OK. Let's put it back together and....*boom* — it started. It ran and idled fine, responsive to the throttle and everything, but under a load it kind've seemed to bog down and stalled out.
I had to leave it for a week or two, but got back to it. Given that I was messing w/ the fuel and fuel injectors, I pulled them again, and this time tried to clean them out with a jerry-rigged canister of carb cleaner to keep it under pressure. Assembled them again and... *boom* ... started fine and idles nicely, responds to throttle, etc. I poured a bottle of seafoam into the tank, in hopes of doing something.
My dad has taken it for a few rides...says it's a bit "rough" sounding, but OK. Then, yesterday, he is riding it again...rides about 2-3 miles. Stops for a meal. And then it won't start, just like before.
What could it be? Water in the fuel? Why would run it sometimes? What would pulling off the fuel injectors and then putting them back on do? (I'm assuming they weren't dirty, though I did try and clean them). Why would it come back to life (for a little while) after pulling out the fuel injectors?
Thanks for any thoughts!