First time bike maintenance

[wacho678]

Hey all.
I picked up a 2006 ninja 250 last fall for 1500$. First bike, the previous owner seemed like a good caretaker. I started noticing a few issues at the end of the season and then stored the bike for the winter. My main issues are as follows:

Fluctuating idle, it would rise/fall by abt 300rpm give or take once it got warm.
Knocking when I let out the clutch in neutral
Very laggy throttle, when I let off it drops rpms very very slowly

I also have to get new tires and probably adjust my chain as well.

Anyway, I wanted to tackle basic stuff first and decided to tackle the carbs. I got them off, opened, cleaned and attempted to bench sync(Thank you ghostt). I noticed my pilot jets were slightly messed up, not quite stripped but a little bit damaged. I also found that one of the diaphragms was ripped so that it wouldn't seal and the slide was not opening properly.

As it stands my bike is sitting in pieces and I'm waiting for new diaphragm to come in. Does anyone have any advice on how to move forward, particularly with the idle issues(whether it is a carb sync, new parts, or valve adjustment) and the laggy throttle. I read that the knocking in neutral is normal/ hopefully a nonissue. I wish I had a video of how it runs for more context I can dig thru and see If I can find one.

Sorry for the wall of text, thanks in advance.

[Triple Jim]

Welcome to the board, Will!

Fluctuating idle speed could indicate misadjusted or dirty carbs, or out of adjustment valves. If you don't know when the valves were last adjusted, it would be worth going though that procedure very soon. Out of spec valves can make you chase carb problems forever.

The knocking sound in neutral with the clutch lever released is probably the old clutch rubber dampers not doing their job, and it's mostly just a matter of the noise. Mine does it a little.

Ducatiman here on the board is the resident carb expert, and can get them into new condition quickly at a reasonable price. Don't hesitate to ask him questions or send him your carbs.

Here's a diagram showing the hard-to-clean passages: https://n4mwd.blogspot.com/2013/10/s...-passages.html

[ducatiman]

welcome Will.

to be able to do carbs...a few tools necessary.....
you must have access to powerful compressed air, not from a can, but from an actual compressor.
An ultrasonic machine also quite helpful, as is soda blasting equipment.
Without it? IMPOSSIBLE.

Anyways, let me know if i can help at all.

[ducatiman]

the ability to turn this into that is critical

[Hogges]

Just follow the service manual to rebuild your carbs. You don’t need any special tools, despite what ducatiman is saying. Just go about it carefully. A laggy throttle on a CV carb comes from a misadjusted idle setting. If the throttle blade is not closing enough, it will prevent the slide from closing quickly. Often people will mess with the idle adjustment to fix carburetor issues, with this unintended consequence.
The float height is also important. Check that carefully. Most likely you already found the main issue with the diaphragm. I’d also make sure that all jets are the correct size.

[wacho678]

Thanks for the responses all. I think if the problems persist post carb service I'll look into a valve adjustment. My carb parts looks clean like in the pic @ducatiman, but could you elaborate on why you need an air compressor and soda blasting vs just a can and some carb cleaner? I'm assuming being thorough and such.

Another probably silly question, but what is the best way to get the wheels off? I'm planning on getting new tires asap and don't have a stand. I'm assuming I should bite the bullet and get one. Any recommendations?

[Triple Jim]

If you have the stock center stand, it lifts the rear wheel off the ground. Once on the center stand, a jack carefully placed to lift the front of the engine, with a block of wood to protect the aluminum, will lift the front wheel. Just be careful.

[ducatiman]

"could you elaborate on why you need an air compressor and soda blasting vs just a can and some carb cleaner? I'm assuming being thorough and such."

Correct, with another before/after pic to prove the point

[Hogges]

Originally Posted by wacho678

Thanks for the responses all. I think if the problems persist post carb service I'll look into a valve adjustment. My carb parts looks clean like in the pic @ducatiman, but could you elaborate on why you need an air compressor and soda blasting vs just a can and some carb cleaner? I'm assuming being thorough and such.

Another probably silly question, but what is the best way to get the wheels off? I'm planning on getting new tires asap and don't have a stand. I'm assuming I should bite the bullet and get one. Any recommendations?

You don’t need a stand. You can lift the rear tire and support it with a piece of two by four or jack under the right side footpeg or similar. Same for lubricating the chain. Then when the rear wheel is done and back in, you can lift the front by putting a jack under the front of the engine. In both cases you use the side stand and the other tire still on the ground to make a tripod, basically. I have done many tires like that, or oiled chains. The front is a little more awkward because the steering will of course swing to the left side unless you strap it back to the frame.

[CaliGrrl]

Welcome to the board!

My friend had ducatiman rebuild her carbs and he did a stellar job.

[wacho678]

So I got the new diaphragm but I'm confused on how to get the old one off the slide. Something something soak in hot water and pull it off? I'm tentative to just pry it off in the event the slide breaks.

[ducatiman]

S...T...R....E....T....C....H it..... both off and on.

[wacho678]

Roger Dodger. Thanks for the help y'all