AaronBND
TY 4 Stroke Junkie
Just curious guys. I took my sled out today after doing the float bowl updates and the new airbox and it did great. Did really well all the way through except when I shut it off. When I go to restart it , it fires right up but seems to be loaded up and has to kinda blow-out. Any ideas? The new airbox must flow a little better cause I didn't have that problem with the pipe alone. Thanks!
Aaron
Aaron
AaronBND
TY 4 Stroke Junkie
Wow! Nobody?
Is it backfiring? New air box is it stock and what is this pipe you talk of. We need more info the better you explain the better we can help.
AaronBND
TY 4 Stroke Junkie
It's a glass-pac pipe like a few guys on here have done. No problems at all going to it. Rode it a few times with no trouble. I just did Kachess' airbox mod and I guess it flows better than the stock one. It runs strong all the way through. No problems other than restarting it loads up a little. I'm thinking it's running a little lean now.
Aaron
Aaron
If you mean hard starting after it is warm all you have to do is give it a little throttle when cranking it over and it will start right away. You may need to install a valve to shut off the coolant going to the carbs. I did this with mine and it starts better when off only need it when it is really cold. If it is running lean the only way to cure that is go back to stock air box or jet up a bit.
AaronBND
TY 4 Stroke Junkie
I put in the first post "it fires right up but seems to be loaded up and has to kinda blow-out". I know about cracking the throttle to start it. Main jets are for 3/4 to full throttle. It was 34 degrees today so I don't think it was a coolant issue. Thanks!
Aaron
Aaron
Turbo Tim
TY 4 Stroke Master
Might want to check your float levels ,if your flaots are too high , a little gas will seep into the carb throats and cause it to be rich when you try to start it.
AaronBND
TY 4 Stroke Junkie
Would the float-bowl updates of affected this Tim? Thanks.
Aaron
Aaron
Turbo Tim
TY 4 Stroke Master
AaronBND said:
Doesn't seem like it unless one of the tabs on one of the floats got tweaked a little bit or something.It could even be something like a speck of debris caught between the needle and seat .
Rx1M5
VIP Member
Is the problem worse if the sled is sitting pointing slightly downhill? Mine does the same thing. I lowered my floats and much of the problem cleared up. I am going to reduce my pilot jet by one size but its not bad enough that that I'm willing to make a project out of it. On days when the barometric pressure is low it will do it more but like I said I can live with it. Once I lowered the floats the downhill stalling problem went away which was the only one that was really getting to me. All in all runs pretty strong now. I'd take a look at your float level if for no other reason then to rule it out as a cause. A Yamaha mechanic I know said the RX's were delivered with pilots that were way too fat.
M5
M5
AaronBND
TY 4 Stroke Junkie
Good to know. That's like me, not sure I want to make a project out of it. Just wondering if it was something easy. I am going to put new plugs in it and run them for a week or so and see how they look and maybe go from their. The float-bowl update did fix the up and downhill stalling. Thanks for the post.
Aaron
Aaron
Kachess
TY 4 Stroke Junkie
Where are your needles. We run our's with the clip in the center position, or one higher (needle lower) for 3 to 6k feet. Never messed with jets. Always have to crack throttle to start. Sometimes have to clean it out on starting if it's warm out. All the guts back in your airbox? Trim the intake boot? I noticed leaving anything out seems to screw things up.
AaronBND
TY 4 Stroke Junkie
Well it was actually 34 degrees that day. Wonder if that was it? Like I said it runs awesome under full load, just had to blow it out a little on restart. Not sure where needles are. Will check them. We are about 5-8K so where should I have them? Box is complete! You get your mail?
Aaron
Aaron
Kachess
TY 4 Stroke Junkie
Got the $. Thx. Any trouble just give me a PM.
Trxster
TY 4 Stroke Junkie
Turbo Tim said:
Actually I believe it is because of the new bowls...they have the tube in there which when the carbs are warm at all (34' is warm....trust me) they pressurize the bowls and that sends gas up the tube and through the needle which is why it loads up. Next time you have the bowls off.....check the float height and set them out to 15mm. Also, the coolant shutoff is the easiest to add.... and when it was 34' my coolant would be off. You don't need the coolant at all unless it is cold (like 10'). Even then I usually crack it open to start and warm up then turn them almost all the way off. I did end up going to 15 pilots and turned my fuel screw in a bit (1.25 turns) and it started real good. Good luck.
Rt
