Hi guys! . . . (XJ750R) I got my carbs all cleaned up and put back together, put in fresh fuel and lines, and a new air filter.

The bike turns over fine, starts up revs a little bit then immediately dies. I'm not good at diagnosing these things, seems like it might be starving for fuel so possibly I mucked something up during the carb job. Is this problem recognizable to anyone here?

Thanks in advance.

Something I just though of. . . . .

On the top side of the carbs there is a screw/spring that goes in next to the choke assemblies. I did not know how to adjust this, so I screwed them all the way in, then backed them out 2.5 turns. Could that be part of the problem?

KTA - check out the tech stuff. Sounds like you need to take off your carb and clean it out. From there, you need to reset the mixture screws (all the way in, then out 2.5 turns).

Other things to check
- are you getting fuel?
- was it running before?
- have you checked your coil resistance? (Sometimes the spark plug ends wear out)

Just some 101 bike maintenance KTA. Been there. Done that! Let us know how you make out.

The carbs are cleaned! The mixture screw is 2 1/2 turns out! (didn't I say that?)- haha

I definitely have fuel in the bowls.

I purchased the bike in none running condition. The carbs were very clogged up, now they are clean and shiny. . though I may have to tear into them again. I'm going to check all 4 spark and compression's tomorrow and go from there.

I'll keep you all updated. Thanks mr. fork.;

Spark and compression is good. So into the carbs I go. . . ugh.

Oh yeah, check your float fuel levels (from the tuning section in the links)

Low floats will starve the engine of fuel.

Upon further investigation I think it's actually stalling due to flooding. I've gone through the floats a couple times, they all move freely and are set to 17-18mm but some gas is still getting through the float valve assembly when they should be closed. I think the little rubber tips may be the problem, although they don't appear to be very worn. I'll do some more fiddling and let you all know.

Hey,

Do you know how to properly set your float heights? I can try to find the writeup. Good idea is to buy the XJ 3.0 CD. It's got great tips and tonnes of manuals. It even has the FSM for your bike.

Sounds like you all you need to properly set your float levels...

Well I've set floats on other bikes before, and I found a spec page online that said the XJ750 floats should be set to 17.5mm so that's what a went with. It's kind of strange actually, when I check the float level by attaching a clear tube to the bowls they all look nice and level and are just a little below the gaskets. But if I let it sit for a minute or two the levels will start to rise and gas will leak out the carbs, that's what leads me to think the little rubber nubs on the float valve assembly are not sealing properly. . . . Anywho, thanks for the help Mr. Fork, it's appriciated.

just a thought but is the tap on the tank vaccume operated? the same as the 550?
does it shut off the petrol ok when the engine is stopped? probably nothing to do with the problem but i thought id chirp in ;)

By the sounds of it your float needles are worn KTM. I've always used the clear tube method for float leveling with great results. (7 different XJ750's now).

Zanotti motors should have replacements. http://www.zanottimotor.com/info.htm

I've ordered several parts from them. Great service too from the guys.

Ed