I understand Ca 2017 TW jetting is way too lean, and my bike is stock. I have the carb apart currently to replace bad needle and seat, what jetting is recommended by you been there done that people?
Thanks in advance
Jetting typically is lean from the factory. I wrote up a how-to a week or two ago. Rather than make you do a little leg work using the search feature, I've decided to grace you by copying what I wrote and pasting it here. It's a little different than your situation since you have the carb off, but you'll figure out those differences and make it I suppose. So, here's the down-low on how to set up the carb, Ski Pro 3 version;
First, my mods are;
1. Pilot fuel mix screw set 2.5 turns from full in. (turn in to seat, then back out 2.5 turns)
2. I used two shims. Ordered from Amazon here; .010" shim from Amazon
3. I up sized my pilot jet from #30 to #34 Here's the pilot jet I bought from boats.net website
5LB-14342-17-00 JET, PILOT (#34) (Yamaha Motor) $7.94 Also, here's a link for the jet from Partszilla; #34 Pilot Jet
4. I did NOT change my main jet size. Mine runs fine from sea level to over 7,000' elevation with the changes I made.
5. I replaced all the bowl Philips head screws with Allen head stainless steel screws purchased at the local hardware store. Now is a good time to do that.
My bike is a 2013. Your carb on a 2017 is the same.
The Pilot mix screw is located under the carb nearest the motor. There is a metal cap over the screw head. Poke a small hole into this and use a screw to thread in a tiny bit so you can pull this cap off. Use a flat blade small screw driver to find and adjust as follows;
1. Screw the adjustment in all the way using a flat blade screw driver, seating very lightly so you don't damage the o-ring.
2. Back the screw out 2 and 1/2 turns. This is the start point. I ended up only 2 1/4 turns out when I did the final adjustment which is done with ethe motor warmed up. Take a ride for a few miles, make sure the bike is fully operational temperature, then adjust for the max revs. Set throttle idle adjustment as needed as the RPM's increase.
The Pilot jet is accessible by loosening the carb boots and rotating the carb bottom towards the left/shifter side. You may have to remove the seat and tank in order to get enough slack in the throttle cable, but you will not have to remove the carb. Now you should be able to remove the carb bowl. The pilot jet is recessed up in there. Use a flat blade screw driver to remove it. Partszilla link I attached earlier will have an exploded diagram of the carb for locating the pilot jet if you are unsure.
The shims are installed on the needle. The needle is accessed via the top of the carb. Roll the carb so the black top is now towards the shifter side of the bike. Take the black top off. Be careful and remove the diaphragm. There will be a large spring, a white plastic cap of sorts, a small spring under that and the needle. The needle will have an E clip and a white spacer. Remove the white spacer, and put one shim on, then put the white spacer back on. You can do this without removing the e-clip. Reassemble being very careful with the order of the springs.
The pilot screw is adjusted for highest RPM when the bike has been well warmed up, but starting a 2.5 turns is a good place to start. However, I found it had little effect until I increased my pilot jet size so keep that in mind.
The replacement #34 pilot jet will make the bike start so easy, you probably won't need the choke unless the temperature is below 50 degrees. Yamaha jetted this bike so lean, it's a bitch to warm up.
The needle shims lift the needle, allows more fuel when the throttle is barely opening and cures that dead/flat spot in the throttle right off idle.
I recommend you take photos as you go along in case you need refresh how things go together. You do not need to pull the whole carb unless you really want to. Hint; you do not really want to...
I also recommend you have the shop manual in front of you or at least an on-line manual that shows all the parts and the assembly order.
Here's a link that has photos of the needle and shows the pilot screw covered by the cap, but it's the TK carb, not the late model carb. The needle shim set up is the same. This link shows upsizing the main jet, not the pilot jet. Look for the pilot jet hole. the jet is recessed in a bit. Carb Link 1
This link is to a description on the process of accessing the needle and the pilot jet. Reading this will help understand what you need to do. Carb Link 2