Im perplexed with carb issue
08-23-2009 | 09:05 PM
#31
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From: altoona, pa
you may be right, but i don't know. You ordered a new one-how much did it cost? It seems like there is spring in it and an arm coming out the back that hooks on to the throttle control putting a little spring pressure on it, but I really don't know. That's what it seemed like to me. When you hook the arm on to the throttle, you can turn it clockwise til you feel spring pressure. If yours can do this, perhaps it's okay. Did you set the air mixture?
08-24-2009 | 09:12 AM
#33
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From: altoona, pa
range, pipes/plugs light brown/grey color. (OEM mufflers with rear baffle removed. Carb and midpipe restrictors still in tact. PAIRS removed.)
if you can't hook it onto the throttle and turn it clockwise til you fell the spring pressure, likely broken.
08-27-2009 | 06:27 AM
#34
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Superstock
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From: Muskego,WI
carb issue
So i was able to replace the TPS and got it set to 498 ohms....
I shimmed the needles with 1 # 4 Brass washer... I think I should have went two as it is down on power from 3-5 k....
hopefully one more washer should do the trick...
I shimmed the needles with 1 # 4 Brass washer... I think I should have went two as it is down on power from 3-5 k....
hopefully one more washer should do the trick...
08-27-2009 | 07:42 AM
#35
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From: altoona, pa
what is the thickness of a #4 brass washer?
08-27-2009 | 08:10 PM
#37
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From: altoona, pa
09-07-2009 | 04:10 PM
#38
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From: Muskego,WI
perplexed again....
I dont have any vaccum leaks, tps is set to 498...
So i shimmed with one washer (#4 washer, appx. .026 or so) huge flat spots.
I then went back to stock and the bike runs great, but for an hour or so. After an hour of hard riding, it starts to act up. stumbling, bucking, generally doesnt want to run after an hour or so of use.
For the first hour, the bike pulls like a raped ape, but like i said after an hour it starts to run like ****...
any ideas? what would do this... currently the bike is stock with the jetting.
I dont have any vaccum leaks, tps is set to 498...
So i shimmed with one washer (#4 washer, appx. .026 or so) huge flat spots.
I then went back to stock and the bike runs great, but for an hour or so. After an hour of hard riding, it starts to act up. stumbling, bucking, generally doesnt want to run after an hour or so of use.
For the first hour, the bike pulls like a raped ape, but like i said after an hour it starts to run like ****...
any ideas? what would do this... currently the bike is stock with the jetting.
09-07-2009 | 07:15 PM
#39
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From: altoona, pa
I guess no one else wants to put their two cents in. Looks like I'm the only one trying to help you.
I don't know what the problem is. Get Oct. Cycle World and look at p 84 "American Idle" that describes a number of issues that can affect carbs/fuel and describes some testing methods.
When it starts all that ****, pull the plugs and see what they look like. Maybe you should go back to stock jetting. Mines stock jetting and just the mods i described earlier and it runs great.
I don't know what the problem is. Get Oct. Cycle World and look at p 84 "American Idle" that describes a number of issues that can affect carbs/fuel and describes some testing methods.
When it starts all that ****, pull the plugs and see what they look like. Maybe you should go back to stock jetting. Mines stock jetting and just the mods i described earlier and it runs great.
09-07-2009 | 08:32 PM
#45
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From: altoona, pa
The reason I suggested the Cycle World article was that symptoms occurred after an hour of riding possibly indicating lean fuel condition. there's likely many possibilities, but if you do the **** suggested, at least you know it's not those that are causing your problem.
09-08-2009 | 12:11 AM
#46
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Joined: Dec 2005
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From: Sunshine Coast, Australia
Nasty.
I would try a good base setting for your jetting. With a free flowing exhaust standard jetting will be too lean anyway. I am not sure what mods you have done, but if it is just pipes and filter then you can get some basic specs off this forum to start with. This should have the jetting pretty close, and you can look at other possible causes.
A FULL carb strip down and clean would be a good idea when you change your jetting specs next. Make sure evertthing is perfect. Same with all vent tubes and hoses etc. I would also make sure your tank vent is not partially blocked.
Synch the carbs. If it runs too rough to be able to do it, then maybe you can get a rough indication by looking at them on the bench when you next have them off.
These problems can be hard to find.
I would try a good base setting for your jetting. With a free flowing exhaust standard jetting will be too lean anyway. I am not sure what mods you have done, but if it is just pipes and filter then you can get some basic specs off this forum to start with. This should have the jetting pretty close, and you can look at other possible causes.
A FULL carb strip down and clean would be a good idea when you change your jetting specs next. Make sure evertthing is perfect. Same with all vent tubes and hoses etc. I would also make sure your tank vent is not partially blocked.
Synch the carbs. If it runs too rough to be able to do it, then maybe you can get a rough indication by looking at them on the bench when you next have them off.
These problems can be hard to find.
09-08-2009 | 06:59 AM
#47
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From: altoona, pa
09-08-2009 | 03:42 PM
#49
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From: Phoenix, AZ
But it is actually possible you have bad coils, because they will misbehave when hot. Not saying this is for sure, but if your problem is only when hot, it might be worth checking.
09-08-2009 | 03:57 PM
#50
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From: Belgium, WI
I am starting to think that if it runs fine for the first hour that it may be an electrical issue. these would normally show up sooner, but there are no good reasons why it couldn't be a coil or cdi that just starts to crack up after they see some heat after extended riding. The hour of riding is what gets me...
09-08-2009 | 08:01 PM
#51
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From: Muskego,WI
well today took it for a ride and it acted up about 7 minutes into the ride.... choke did help some, but the rpms hang way up as I pull the choke out when riding at about 35 mph, is that normal to show a lean condition
09-08-2009 | 08:35 PM
#52
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From: Belgium, WI
the choke system that we have rely on needs vacuum to operate (i.e. closed throttle), the more open the throttle, the less fuels is added. But anywho, I just thought of something that I noticed about our choke. The elbow can be pulled out of the plastic nut that threads into the carbs. make sure that one of those isn't mis-routed.
I think that at this point, everyone here and you are ready to throw the kitchen sink at it. For us, its the lack of contact with the bike. There are many people that are very skilled on this forum, but like any vehicle problem, interpretation and descriptions lead to something lost in translation. Good luck, and let me know if you need help beyond couch quarterback.
I think that at this point, everyone here and you are ready to throw the kitchen sink at it. For us, its the lack of contact with the bike. There are many people that are very skilled on this forum, but like any vehicle problem, interpretation and descriptions lead to something lost in translation. Good luck, and let me know if you need help beyond couch quarterback.
09-08-2009 | 08:43 PM
#53
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From: Muskego,WI
thanks Bill I agree. I need to get to the bike, As I got alot of **** going, work travels, etc. winter should be a good time to work on the jetting!!!!!!
i am going to shim the needles to about .060 and see if that does anything, should richen enough to get through the season then look at the dyno for help with the jetting.
i am going to shim the needles to about .060 and see if that does anything, should richen enough to get through the season then look at the dyno for help with the jetting.
09-08-2009 | 11:14 PM
#54
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From: Sunshine Coast, Australia
Mixture requirements for an engine will change with temperature. The warmer it is the less fuel is needed. This is why you use a choke when cold.
I stand by my jetting comments above. Use a setting that lots of bikes use, and then you can rule out that possibility I think. This will allow you to look elsewhere, unless it fixes the problem.
I stand by my jetting comments above. Use a setting that lots of bikes use, and then you can rule out that possibility I think. This will allow you to look elsewhere, unless it fixes the problem.
09-21-2009 | 07:54 PM
#55
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From: Muskego,WI
hopefully problem solved... looking back at when it started acting up... I was putting the seat on. I knocked the electrical connection for the gas tank loose.
finally followed the KISS method and took 1 minute to track down after steping back for a week (forced work trip)
finally followed the KISS method and took 1 minute to track down after steping back for a week (forced work trip)
09-27-2009 | 06:39 PM
#57
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From: Muskego,WI
you are correct Shayne my problem has not been fixed....
so it ran well for an hour or so then acted up.... I looked over the carbs, cleaned, etc. no vacuum leaks that i could find.
symptoms -
low rpm - off idle to 3k runs really rough ( sputter, miss, occassional dieing)
above 3k it will pull hard in first ( will wheelie, etc.)
the bike still has a 3k-4k carb fart, but right now I need driveability down low...
DO you think a 48 pilot is in order... i think this hawk needs move fuel.
what do you guys think????????
so it ran well for an hour or so then acted up.... I looked over the carbs, cleaned, etc. no vacuum leaks that i could find.
symptoms -
low rpm - off idle to 3k runs really rough ( sputter, miss, occassional dieing)
above 3k it will pull hard in first ( will wheelie, etc.)
the bike still has a 3k-4k carb fart, but right now I need driveability down low...
DO you think a 48 pilot is in order... i think this hawk needs move fuel.
what do you guys think????????
09-29-2009 | 06:59 PM
#58
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SuperSport
Joined: Dec 2005
Posts: 963
From: Sunshine Coast, Australia
The problems you describe are too bad for it to be a slight jetting change, and from memory your jetting specs have been discussed at length and are pretty close to being right.
I would be checking for air leaks using water. Get a spray or bottle that allows you to spray water in around certain parts, and then carefully do each bit at a time. If the engine runs REALLY bad at one spot that may be an air leak that you hit.
This thread is also getting too long to remember all you have done, so maybe you should put up a list of components you have tested. For example, have you checked the plastic choke fittings are not broken?
Maybe it is time to get a shop to give you some help.
I would be checking for air leaks using water. Get a spray or bottle that allows you to spray water in around certain parts, and then carefully do each bit at a time. If the engine runs REALLY bad at one spot that may be an air leak that you hit.
This thread is also getting too long to remember all you have done, so maybe you should put up a list of components you have tested. For example, have you checked the plastic choke fittings are not broken?
Maybe it is time to get a shop to give you some help.
09-29-2009 | 07:17 PM
#59
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From: altoona, pa
Good call Shayne.
10-20-2009 | 01:59 PM
#60
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Squid
Joined: Oct 2008
Posts: 49
From: San Pedro, Ca
I had an odd problem recently that was similar... actually the symptoms were a little different but it's worth a look. Try disconnecting the petcock vacuum line (to the rear of the petcock pointing to port) and see if any gas comes out... I just replaced my petcock vacuum diaphragm, and it fixed a problem where my bike would run fine initially then go to hell after about 1/2 hour of running.
