Clunking noise, and slight stutter when take off
07-25-2008, 09:20 PM
#1
Junior Member
Squid
Thread Starter
Join Date: Jan 2008
Posts: 20
Clunking noise, and slight stutter when take off
I've had this bike for alil over 2years now and really don't know bout bikes. I've tryied looking into this and found several threads about the same problem but wanted a second opinion. i bought the bike with i think bout 12,000 miles on it and have bout 19,000 on it now. it has D&D pipes. i found out about a year ago that the bike has had other mods done to it... it has been bored out with over size head and & cams something done with the carbs... etc etc etc. (i met the orginal owner coincidencly at a gas station and spoke with him for a slight second so i really don't know)
when i bought the bike it had a clunking noise kinda like a chain slapping against the front of the engine around 2500 to 3500 rpm along with a slight hesitation or slight jerk. it never does it at any other rpm. it does it sometimes when warming up at that idle also.
i haven't riddin the bike in a while, i just replaced the air filter to a K&N filter and took it out for a ride. the past 2 days the clunking noise seems to be even worse. (it doesn't help that i live in a small town witch the speed limit is 30mph)
i noticed that when i take off it is very hesitant. it also died out couple of times from a dead stop taking off with the same clunking noise except it seemed louder.
things that i think i need to do... adjust (jetting) the carbs bcause of the K&N. mayb 0W 40 oil???
i just want to know if it would hurt the bike if i keep ridin like this and mayb some tips. thanks
when i bought the bike it had a clunking noise kinda like a chain slapping against the front of the engine around 2500 to 3500 rpm along with a slight hesitation or slight jerk. it never does it at any other rpm. it does it sometimes when warming up at that idle also.
i haven't riddin the bike in a while, i just replaced the air filter to a K&N filter and took it out for a ride. the past 2 days the clunking noise seems to be even worse. (it doesn't help that i live in a small town witch the speed limit is 30mph)
i noticed that when i take off it is very hesitant. it also died out couple of times from a dead stop taking off with the same clunking noise except it seemed louder.
things that i think i need to do... adjust (jetting) the carbs bcause of the K&N. mayb 0W 40 oil???
i just want to know if it would hurt the bike if i keep ridin like this and mayb some tips. thanks
07-25-2008, 11:29 PM
#2
Thats Mr Dill hole to you
Superstock
Join Date: Aug 2007
Location: Sioux Falls, SD Beeeotch
Posts: 389
I would search the CCT threads if you have the original CAM Chain Tens. with modified heads etc it may have caused premature wear just and idea. I would stop Riding the bike
until you rule out the cct's if they go you talkin big time money to fix it.
until you rule out the cct's if they go you talkin big time money to fix it.
07-25-2008, 11:43 PM
#3
Senior Member
SuperSport
Join Date: Dec 2005
Location: Sunshine Coast, Australia
Posts: 963
It sounds like you need a good tune up or some jetting work.
But, just as a hunch, I would try some high octane fuel first. What you are hearing may be detonation if you have an increased compression ratio, which is common with modified engines. Higher compression ratios require higher octane fuels, so I would try this as an experiment.
But, just as a hunch, I would try some high octane fuel first. What you are hearing may be detonation if you have an increased compression ratio, which is common with modified engines. Higher compression ratios require higher octane fuels, so I would try this as an experiment.
07-26-2008, 04:32 AM
#4
Senior Member
SuperSport
SuperSport
Join Date: Dec 2006
Location: Victoriaville, Quebec, Canada
Posts: 880
You definitely need to re-jet the carbs, or to go back to the stock filter.
You probably have a DJ kit installed, but you don't have the other jets that comes with the kit.
Try to pull the needles one notch (lower clip), that may cure it, if you say it'S ok at WOT
The noise you hear is likely to be an airbox backfire, you usually feel it on the tank.
If the needles adjustment is already maxed out, you need to increase the pilot jet by a bit.
You probably have a DJ kit installed, but you don't have the other jets that comes with the kit.
Try to pull the needles one notch (lower clip), that may cure it, if you say it'S ok at WOT
The noise you hear is likely to be an airbox backfire, you usually feel it on the tank.
If the needles adjustment is already maxed out, you need to increase the pilot jet by a bit.
07-26-2008, 11:04 AM
#5
Junior Member
Squid
Thread Starter
Join Date: Jan 2008
Posts: 20
Thanks guys for the tips.
i am going to try to adjust the CCT which could cause this also..?...
so i am reading and looking into more about the CCT
also i have tryied higher actane fuel with new spark plugs before (not with the K&N), seemed like it was wanting to run faster but needed to be adjusted, noise was still there even after runnin a few tanks with higher octane so went back to the cheapest fuel.
gboezio is right it almost sounds like my carb is back fireing in my air box. also when i took my stock air filter out which it was a lil dirty but on the bottom metal side it was black stuff on it. kinda looked like back fire along with some oil. i dont know if that is a sign of anything but im going to look into that also.
havent adjusted my carbs yet but im going to be doing that along with adjusting my CCT to see if that helps.
if it still acts up im thinking about going back to the stock air filter to see if that helps any. which ive seen alot of people say the stock is better then the K&N, but since its been tuned alil i wanted to try the K&N.
i think im taking the right approach, if anyone has any other suggestions please let me know.
Thanks
i am going to try to adjust the CCT which could cause this also..?...
so i am reading and looking into more about the CCT
also i have tryied higher actane fuel with new spark plugs before (not with the K&N), seemed like it was wanting to run faster but needed to be adjusted, noise was still there even after runnin a few tanks with higher octane so went back to the cheapest fuel.
gboezio is right it almost sounds like my carb is back fireing in my air box. also when i took my stock air filter out which it was a lil dirty but on the bottom metal side it was black stuff on it. kinda looked like back fire along with some oil. i dont know if that is a sign of anything but im going to look into that also.
havent adjusted my carbs yet but im going to be doing that along with adjusting my CCT to see if that helps.
if it still acts up im thinking about going back to the stock air filter to see if that helps any. which ive seen alot of people say the stock is better then the K&N, but since its been tuned alil i wanted to try the K&N.
i think im taking the right approach, if anyone has any other suggestions please let me know.
Thanks
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