Pilot screw messing me up?
02-11-2018, 01:14 PM
#1
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Pilot screw messing me up?
After the carb rebuild ive been getting some odd cruising behavior.
At 60mph in 4th the bike surges causing the chain to slack and slowly buck at times.
Idles great and when im WOT it pulls without a studder.
When I did the rebuild I put 48 jets in and set the Pilot screw to 2.5 turns out. I dont have a way of doing an idle drop adjustment with the current setup, although JackFlash has those nice screws.
Could this adjustment at 2.5 turns be giving me this sort of behavior?
At 60mph in 4th the bike surges causing the chain to slack and slowly buck at times.
Idles great and when im WOT it pulls without a studder.
When I did the rebuild I put 48 jets in and set the Pilot screw to 2.5 turns out. I dont have a way of doing an idle drop adjustment with the current setup, although JackFlash has those nice screws.
Could this adjustment at 2.5 turns be giving me this sort of behavior?
02-11-2018, 02:04 PM
#3
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I believe it was 4k in 4th at 60mph.
5th and 6th I really never use because they lug real bad unless the bike is WOT.
Are you talking about the main needle raising it up? I think the main needles were aftermarket but set at stock settings if I remember right. I can toss a washer in there. That should be about .5mm
5th and 6th I really never use because they lug real bad unless the bike is WOT.
Are you talking about the main needle raising it up? I think the main needles were aftermarket but set at stock settings if I remember right. I can toss a washer in there. That should be about .5mm
02-15-2018, 11:04 AM
#5
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To get rid of the surge (lean spot) would then be either open the pilots more (try a 1\4 turn open and see what happens) or like I stated earlier, raise the needles a little bit.
I doubt you will need to go too far from where you are at now. Just make 1 change at a time and keep the adjustments small and you should get it dialed in soon.
02-15-2018, 10:37 PM
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I had a similar surging at low to mid throttle opening at 2-3500rpm in upper gears when I bought my '98 Firestorm(Superhawk) 5 years ago. Before i even started straightening out the jetting, I set the TPS a@ 500ohms, because that's what this forum suggested and curiously the surge was gone.
02-16-2018, 12:55 PM
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I also just adjusted the TPS to 500 recently and some of the surge went but not enough for the bike to be fun to ride yet.
Its terrifying having the bike lunging when at 45mph in traffic.
Its terrifying having the bike lunging when at 45mph in traffic.
02-16-2018, 04:51 PM
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Im going to try just moving the needle from #4 to #5. washers in the same place. Its about .8mm of an adjustment.
Also checked the pilot screws again and they are in fact 2.5 turns out.
Also checked the pilot screws again and they are in fact 2.5 turns out.
02-17-2018, 06:29 AM
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The rubber bit at the front of the box is there yea. I replaced the screws to the box because there were only 4 of 8 on there.
Looks like there is supposed to be some plastic "skins" in the front of the frame but I have nothing there. Maybe too much air is coming in the front end?
Also noticed that the slides had 3 lift holes. Should I cover over the one that was drilled for the dynojet kit?
Looks like there is supposed to be some plastic "skins" in the front of the frame but I have nothing there. Maybe too much air is coming in the front end?
Also noticed that the slides had 3 lift holes. Should I cover over the one that was drilled for the dynojet kit?
02-17-2018, 07:44 AM
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After reading the huge carb thread sticky I think I should be looking for stock needles and springs and doing the slide mod.
Anything to get the bike running good.
Anyone have stock needles and springs laying around?
Anything to get the bike running good.
Anyone have stock needles and springs laying around?
02-17-2018, 09:22 AM
#17
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Floyd,
Buy and instal #1 and # 3 ( Not sure what #3 is ) before you do anything else. That part is there for a reason, not sure what but it serves a purpose.
Early on in the piece I removed that part when I first started mucking around with the VTR.
I can't remember the symptoms however I know my bike didn't run properly.
I refitted it and problem solved as bike ran much better. You will have to remove the carbs and there are a couple of clips that hold it in place.
I have seen these parts on fleabay for about $20 bucks.
Also, when I did my DJ kit I drilled the slides only to experience a change for the worse. I refitted standard slides and the bike went a lot better.
A pain I know but get it right and you will be happy.
Buy and instal #1 and # 3 ( Not sure what #3 is ) before you do anything else. That part is there for a reason, not sure what but it serves a purpose.
Early on in the piece I removed that part when I first started mucking around with the VTR.
I can't remember the symptoms however I know my bike didn't run properly.
I refitted it and problem solved as bike ran much better. You will have to remove the carbs and there are a couple of clips that hold it in place.
I have seen these parts on fleabay for about $20 bucks.
Also, when I did my DJ kit I drilled the slides only to experience a change for the worse. I refitted standard slides and the bike went a lot better.
A pain I know but get it right and you will be happy.
Last edited by kenmoore; 02-17-2018 at 09:25 AM.
02-17-2018, 09:49 AM
#18
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Im going to fill the holes in the slides so ill have one lift hole in the front and two in the rear per the carb sticky.
I wonder if that will work with the current DJ needles and springs though.
I wonder if that will work with the current DJ needles and springs though.
02-17-2018, 12:24 PM
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So first find the plastic bit on e-bay as it will never work right without it.
Then you can mess with the carbs.
02-18-2018, 01:45 PM
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Also found that the plugs are junk and the pair delete was not done right...
The list goes on and on.
At times it feels like I might benefit from just dropping the engine and starting from the ground up.
The list goes on and on.
At times it feels like I might benefit from just dropping the engine and starting from the ground up.
03-13-2018, 10:55 AM
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Ive installed all stock needles and springs and its working great but now I fear I might be a little rich.
The bike starts idles and runs smooth as butter now but im down on power. Its almost bogging when I go WOT.
Im thinking about dropping in the stock 45 pilot jets instead of the 48s that I put in there and seeing what that does for me.
I just HATE that I have to pull the tank and all to adjust the carbs in any way. Oh well, once its right im never touching it again!
The bike starts idles and runs smooth as butter now but im down on power. Its almost bogging when I go WOT.
Im thinking about dropping in the stock 45 pilot jets instead of the 48s that I put in there and seeing what that does for me.
I just HATE that I have to pull the tank and all to adjust the carbs in any way. Oh well, once its right im never touching it again!
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