Aftermarket Main Jet Needle size XJ650 (Y-262 vs Y-10, Y-11 etc)

Hi guys,

So I'm in the process of doing a full carb clean and rebuild where I've bought the following kit on eBay:





In the description for this kit, and also on the Main Jet Needle itself, it says Y262.

I read in another thread on this site (post by @chacal ) that the following original sizes are from Y-10, Y-11 and so on:



So my question is, does anyone here know what the aftermarket Main Jet Needle size Y-262 translates to in terms of the original sizes?

Best regards,

 

If all else fails, clean up and use the original needles. To be safe doing that, you might also want to clean up and use the original needle jets too, so they work together correctly. Or...buy the correct needle and jet pair from Chacal if the originals are not usable.

 

I had a similar issue on tearing down my carbs. and got this from @chacal "Y-262 are the markings on the aftermarket versions of the Y-10 original needles."

 

Hi. Thanks for the replies.

@Huntchuks yes, I might actually do that. They cleaned up fine in my ultrasonic cleaner. Only worry is the difference in needle yet size - see my post below.

@Eric Hughes thanks, that is very helpful. I guess you do not know the aftermarket size version for needle Y-11 ? @chacal - do you? Please also see my notes below regarding cone size of Y-10 / Y262.

As you can see in attached picture, my Haynes manual specifies jet needle size Y-11 for my XJ650 version (4K0). All other jets etc in my carbs have corresponded with the 4K0 version - except for the jet needle which in fact are Y-10.


I guess someone at some point can have replaced the original Y-11 with Y-10, unless there are some exceptions to the specifications mentioned in the Haynes workshop manual?

So the question is, should I try to get hold of new jet needles in size Y-11, or should I keep the Y-10/Y-262 ?

I also noticed that the shape of the Y-10 and the Y262 are not identical.
As you can see in the picture below, the angle of the cone shape breaks at different locations.
I would expect this to have an impact throughout the throttle level?