Won't start

[lt.danhaslegs]

Hi guys, I have a 98 Katana 750. It's been running well for me, but it has had trouble starting. If I start it after it's been sitting for a while, overnight or whatever, it picks right up, but if I don't have the throttle open enough and keep it running, it'll die and can't be revived. I'm assuming that is flooded when this happens. I let it sit for 45 minutes or so, and it'll do the same thing.

Before when I've had this happen, I could just start it kind of "hard" and it'd stay running and I"d be off and on my way. The last two days when I've gone to start it, I've had the throttle wide open the whole time and it'd still die..

I replaced the spark plugs today thinking that would be the problem, but when I went to start it after putting it all back together, I found the same problem, though the old spark plugs were very much in need of a change.

Does anyone have any help? I'm lost at what to do from here and how to diagnose and fix the problem. Thanks very much.

[5forty2]

Why do you open the throttle to start the bike? That is not necessary. Use the start cable (aka choke) and leave the throttle alone, it's not helping.

[lt.danhaslegs]

Why do you open the throttle to start the bike? That is not necessary. Use the start cable (aka choke) and leave the throttle alone, it's not helping.

That was to provide it with more air. That is presuming that flooding has been my issue. Is my logic wrong there? I feel like I'm decently experienced and knowledgeable, but I could easily be overlooking something and misdiagnosing my problems/how to fix it.

When I choke it, it still doesn't start though...

[Kreylyn]

That was to provide it with more air. That is presuming that flooding has been my issue. Is my logic wrong there? I feel like I'm decently experienced and knowledgeable, but I could easily be overlooking something and misdiagnosing my problems/how to fix it.

When I choke it, it still doesn't start though...

The most common thing I see that causes an issue of flooding only after it's been run a while, is the float needles not seating correctly.

Simple to test... fill the fuel lines then blow on them. If you can move air through them at all after the bowls full... then your needles are not seating.

A full cleaning and service of the carbs should resolve that issue for you.

Krey

[lt.danhaslegs]

The most common thing I see that causes an issue of flooding only after it's been run a while, is the float needles not seating correctly.

Simple to test... fill the fuel lines then blow on them. If you can move air through them at all after the bowls full... then your needles are not seating.

A full cleaning and service of the carbs should resolve that issue for you.

Krey

Thanks very much. After looking at the bike the past couple days I've been starting to lean carbs. I didn't want to have to get into it all, but I'm starting to think I will.

A mechanic whom my dad has trusted and has worked on jap bikes since the 60's said I should put in hotter spark plugs. This makes sense to me, I might try it especially if I can return my "new" plugs that I put in the other day. Either way, I'll probably end up working on the carbs.

Thanks so much for the help.

[kat600rdr]

Use the stock type plugs, air filter and fuel filter.. Clean the carbs and replace anything that might need fixed... In the Katana Wiki.. Search Carbs 102 and follow that to clean them.