thinking about trying another brand of jet needle. ive got a 727 13:1 raptor that i cant get exactly where i want it in the midrange. lrd ported head, stage 3 web cam,full exhaust,etc. its been a bit since i messed with it,but with it warming up,im gonna fix it now. pretty sure when i quit back in december on it, the best i could get out of it was either the 2nd or 3rd clip. problem was ,neither one was exactly right. one was too rich, one was too lean. so im thinking of trying another set of needles. anybody ran into this? probably going to try a vitos set and see how that goes. just seeing if anybody had ran into this particular setup before.
727 big bore jetting problems with needle...INFO?
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I assume you're using stock needles right now. What are you running for pilots and fuel screw position and what kind of airbox/intake setup do you have?
When I went from a hacked up airbox to an airbox eliminator setup I had a similar problem with some aftermarket needles and switching to stock seemed to iron out the problem. Perhaps a needle change will help you to if you can't get it honed in.
When I went from a hacked up airbox to an airbox eliminator setup I had a similar problem with some aftermarket needles and switching to stock seemed to iron out the problem. Perhaps a needle change will help you to if you can't get it honed in.
well the jet kit that is in it is dynojet,so im 'assuming' thats what they are. maybe they are stock. i really dont know for sure. i have stock pilots at this point. i went ahead and ordered the vitos to try since i need the 25's anyway. the pilot is not where im having the issue though. its more midrange than that.the fuel screw is where it worked best,and i think its around 2.5 but its been aawhile.stock airbox,but its hacked up to basically just hold the filter in. holes everywhere else.
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The pilot actually provides a progressively decreasing but still relevant amount of fuel throughout the midrange.
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All that money on an engine build, you really should have at least a clamp on filter kit and remove the rest of that lid, if not an airbox elimination kit. Aside from the power increase of a less restrictive intake you'll also be protecting that engine better with a good seal between the filter and intake tubes.
You're lacking without the 25 pilots, get them in for now and that might even resolve your problems.
All that money on an engine build, you really should have at least a clamp on filter kit and remove the rest of that lid, if not an airbox elimination kit. Aside from the power increase of a less restrictive intake you'll also be protecting that engine better with a good seal between the filter and intake tubes.
You're lacking without the 25 pilots, get them in for now and that might even resolve your problems.
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It is kind of hard to help with jetting issues with out knowing what is in the carbs. Throwing a different jet kit at it will have the same affect if you dont know whats in the carbs.
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It would be wise to also give the sympthoms rather then just saying that you think this or that about the jetting.............
bike runs fine, and is jetted pretty close,just has a stumble when held at mid throttle at times. 2nd or 3rd clip is pretty close, but neither one gets rid of it totally. pilot may help, not sure. iim not throwing a different jet kit at it. i needed the pilots anyway,so figured a different needle may be worth a shot if the pilots dont clear it up. bike starts,idles and runs great otherwise..
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Needle Clip Position =
Main Jet Size =
Pilot Jet Size =
Fuel Screw turns out from fully seated =
I ran a dynojet kit in my stock carbs with the mods in my signature other than the x4 cam and it ran fine. The dynojet needles are great and not the problem.
Main Jet Size =
Pilot Jet Size =
Fuel Screw turns out from fully seated =
I ran a dynojet kit in my stock carbs with the mods in my signature other than the x4 cam and it ran fine. The dynojet needles are great and not the problem.
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Describe this stumble in more detail....................
im gonna have to get it back out to ride it to remember exactly. i just wondered if anyone had had a similar situation and had to change needles. i know it blubbered like it was rich on 4th clip or more. 3rd made it better but still there. 2nd pretty good, but seeming to be on the lean side. 1st clip was definately lean for sure.
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The only problem I ever had with my Raptor when driving at about 50 mph at part throttle was if it was too rich and I dropped the needles a notch and all was fine............
thats pretty similar to this id say. i remember dropping it though, and gettin popping on decel. the new pilots should fix that hopefully. i dug around and found 2 more sets of needles i didnt know i had that came with the bike.one set doesnt have a solid taper,but a short quick taper at the top, then a slow taper out to the tip. has 5ND16-56 on them. i assume theyre stock. the ones in the bike and the other set have nothing on them at all.
put in the vito stuff today per the specs in the instructions just to start. bike felt real good so far. rode it 2 or 3 minutes. right when i was really ready to test it, bam ,it dies out of no where. no spark now. always something
after all that, its running better. i had it about done,but felt it needed more fuel than the jets vitos had. 160/165,so i put in 180/185 and it was definately th right thing to do i think. then the stumble was back and had to start over. raised the clip from 4 to 3rd and messed with the pilot a bit and got it back really close again. im holding up there cause it acts like it could still like more fuel,so im gonna hunt down some bigger jets just to give it a try and see before i spend any more time fine tuning it.
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Or to compensate for an air leak. No way should the jetting be that high unless you have an air leak, or the carb floats are messed up.
its not detonation. elevation not sure, im in southern indiana.im running 110 fuel. the stumble is in midrange when held steady. and leaning the needle gets rid of it. what jets should it have then? i see numbers all over the place on here with no real pattern. some ive seen over 200?
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