#50 pilot jets

[elyislander]

Yes I have done some lake riding and it has fresh gas, 91 nonoxy, it holds up longer than 87. Still has cold start and idle issues.

 

[elyislander]

Have not had it out on the trail since putting the 50's in it yet. But had it out on lakes the weekend before, so it has fresh gas.

For the 2nd time this season, I drove it up from my outbuilding to the heated garage to work on it, and all of the little snow we had in the yard melted while it was in the garage. In MINNEAPOLIS no less, so I have pretty well written off riding around here this year. Maybe I'll get out on it in NE MN another time or 2 yet this year, we'll see.

I see you have an 08 vector so you probably do not have an issue with the timing being off. I have given some thought to bringing it to my dealer but dont want to drop a few hundred bucks just to check timing and find out its ok, so maybe i'll tackle that one once shorts and tshirt weather returns. Which should be only a few short weeks away the way things are going!!

 

[elyislander]

ok, just back in from tuning...again. sled does better when warming up, with the 50's in it. No die outs after the temp light went off. its all sync'd and ready to go. still not perfect but I guess I will chalk that up to 'It just aint fuel injected...'

 

[Tabor Rider 973]

About 2 minutes longer warming up after the light goes out works for me.Seems to get rid of frost on drive components too. Also a dose of Sea Foam seems to help the idle and cleans out the storage "cobwebs". Pretty poor year so far here in Vermont.

 

[Metallicat]

Mine acts strange now. With the 45 pilots I couldn't touch the throttle until it was nicely warmed up, otherwise the engine would cut out and die. With the 50 pilots I have the opposite case. I need to give it some throttle after the temp light goes out otherwise it will cut out and die and will not want to restart without some throttle input. I'm guessing that the fuel screws on my sled need to be adjusted to compensate for the larger pilots. I pulled my carbs off again today and inspected everything. Fuel and jets are fine. Even dumped in 4 gallons of fresh fuel and checked the carb sync, they are perfect. So since I have a 2008 my fuel screws are plugged for emissions. I may unplug them before next season to get to the screws. There is little chance I will be able to ride at all this year. Once it is fully warmed up though it seems just fine and will idle nicely.

 

[elyislander]

I have drilled out the plugs and have the screws set 2 turns out.

 

[oldguy2]

Can anyone give me a part no for the #50 jets? I have a 2010 RS Venture carbed 987? engine. Same problem when cold.

 

[elyislander]

8ES-14948-07-00

 

[09nytro]

Any dealer should have them in stock .you will pay out the a## for them from yamaha call local dealer

 

[elyislander]

I ended up having the same problems as Metallicat. I adjusted the fuel screws to 1-1/2 turns out and it is better. The cold idle really only is rough from the time that the temp light goes out until it is fully warmed up. I wish I knew what was going on in the sled that makes such a difference when the temp light goesout. Does anyone know??

 

[twomorestrokes]

These engines are exceptionally cold blooded due to the somewhat aggressive cam profiles. That coupled with the archaic choke and carb system make this what it is when started cold. I never even think about trying to ride or give it throttle until the light goes off. It is interesting that the idle smooths right out an instant before the light turns off on mine.

I always wonder when I hear that some folks have had good luck with the 50's if something isn't partially plugged in their carbs?

 

[elyislander]

That could be, I have done all of the carb jobs myself, focusing on the pilot jets. If it continues to act up It might be time to bring it in to a dealer.

After reading the cam chain tensioner posts and hearing how the shop manual may have misinformation in it on setting the timing marks when the tensioner is replaced, I wonder if my exhaust cam is off since my sled has the new tensioner. Which is why I am curious about how the engine control works during the warmup period.

 

[Metallicat]

I gave up on the larger pilot jets. It just wouldn't idle smoothly after the warm-up light turned off. Back to stock jets. I think if I had the motivation to pull the carbs, drill out the fuel screw plugs, and adjust from there I could have possibly made them work.

 

[lenman20]

I made a carb sink tool today it took 5 min. they were way off. she runs a lot better / smother. i was wondering if this might help you guys out

 

[Metallicat]

My carbs are synced. I have a nice carb sync tool that I use. The problem is once the cold engine light goes off it will not idle with the larger pilots. It needs constant throttle or it will stall. The opposite of the stock jets. Too much fuel and not enough air I imagine. I guess that's why nobody makes carbed 4 strokers any longer.