2003 RX-1ER no top end mid range stumble

[JohnnyG383]

basically all you are doing is making sure they all have the same vacuum. If you are going to keep the sled or work on any carb stuff then I would purchase a set. They hook to the nipples on the intake boots. The carbs adjust by phillips screws on the linkage inbetween 1-2, 23,3-4. So there are 3 screws total that you adjust until all the carbs read the same. Moving one screw changes 2 carbs. Once you do it you will be amazed at how easy it is. Make sure you Y into the vac lines for the fuel pumps so that it will stay running as you do it. You can also build your own , there are plenty of posts on here about it. If you need to buy a set they run $40-$100 online like ebay.
Someone local to you may be able to help too.

Thank you again for all your help carbs are cleaned and back on seems to rev up faster found that one of the fuel needles was stuck in the closed position in one of the carbs. I can’t test it out as it’s raining here since yesterday and the snow we had is shot! I’m going to borrow the gauges from a friend. You say you want to the carbs to be the same but is there a vacuum reading that Yamaha says it should be?

 

[smallheadz]

no just all the same , tons of videos on youtube. Motorcycles are done the same way as well.

 

[Pairodice]

Another good way to check is with an infrared thermometer on the exhaust. If it's been sitting awhile. I would replace all the needle & seats and pilot jets. Check your float level while you are in there and new spark plugs

 

[JohnnyG383]

Another good way to check is with an infrared thermometer on the exhaust. If it's been sitting awhile. I would replace all the needle & seats and pilot jets. Check your float level while you are in there and new spark plugs

Everything looks good in there and I cleaned all the parts even polish the needles and seats I see this problem with a lot of quads I fix. My sled only has 1,070 miles Thanks for the tips

 

[RobX-1]

Here's a link I was going to reference to build my own carb sync tool but then found a new 'old school' MotionPro carb sync that utilized mercury and never built this. Did purchase the stuff to build a four line sync tool but never got around to building it once I had my MotionPro.

https://www.hondatwins.net/forums/3...e-made-carburetor-synchronizer-manometer.html