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  • Sat, May 7 2011 9:35 AM

    Squealing noise during HARD acceleration

    A while back I wrote about this same issue and thought that I had it ( after much help from you all ) -- apparently not though since the problem is still there and, short of splitting the cases, I haven't been able to find it. So, here's the run-down on what's going on, when it happens, and what the problem is NOT ( after looking and trying )....

    2003 Heritage Softail, Twin Cam 88B motor rebuilt with an S&S 106" stroker kit a few years ago, after the build, the engine ran flawlessly but, because I was then using a Power Commander, the engine needed to be dyno tuned so, after my break-in miles I took it to a dyno for tuning. To make a long story short, the dyno shop over-heated the motor and the motor needed to be rebuilt again. The rebuild was done by a local indy shop and after picking it up, the squealing noise started during hard acceleration after the engine and drivetrain get hot. I returned to the shop at least a dozen times and every time they said it was fixed, it wasn't and I quickly changed my opinion about this shop from "he is a god" to "he doesn't know jack" -- I really don't believe that there IS a good and honest harley indy out there any more.

    Anyway, back to the noise ...I can let the engine idle til it gets hot and rev it in neutral ( no squeal ). I can then ride it and crank the throttle wide open within the first couple of miles ( again, no squeal ) but, after riding a few miles -- assuming the drivetrain is hot by then -- and grab a hand full of throttle and there is this squealing noise that, honestly sounds like it is coming from my gas tank or dash. I used to think that it only occured when I cranked the throttle wide open all at once but, after all this time trying to figure it out, I have learned that if I slowly roll into the throttle, once I get over 3/4 throttle the squeal starts -- like it's got something to do with fuel, or throttle position. The problem I am having with it being related to engine speed is, the noise does NOT occur in lower gears -- mainly noticing it in 4th, 5th or 6th ( Baker DD6 trans ). When the squealing noise starts, it continues as a steady "chirping - squeal" ( like a dry bearing ) until I let out of the throttle again. It does NOT just squeak or squeal once and then stop. I have found no signs of metal in the oil.

    I have checked belt tension, primary chain tension ( I did find that the indy left the sprocket shaft extension spacer out so my primary chain alignment was way off ), compensator and stator / rotor. Not sure if my compression releases were possibly leaking so, I removed them and plugged the ports, Checked and installed new cam bearings, intake seals, and exhaust gaskets. I have had the top-end apart and, after finding some scoring in the rear cylinder, replaced both cylinders and piston rings, had the valves reseated and new seals installed, heads shaved .020" and installed new top end gaskets. Compression testing on both cylinders are dead-on at 182 psi each. The Scorpion clutch was also suspect for a while until I learned that I was supposed to be using ATF with this clutch -- the clutch disks were cleaned, everything was inspected for being flat and reinstalled with ATF.

    Have I overlooked anything ? As stupid as it sounds, I swear that the noise is coming from the tank or dash ( it really does not sound like its coming from either side of the engine ) but, it's difficult to tell since the noise can only be duplicated while riding it. Any help or ideas you could suggest would be a help. I am just about resigned to splitting the cases again but, because it sounds like it's IN the tank ( I can't make myself believe that the fuel pump or electrocic speedo is the culprit no matter how much I'd like to believe that ) and I don't want to go through all that time and expense to find nothing is wrong there either.

    HELLO OFFICER, PUT IT ON MY TAB !

  • Sat, May 7 2011 7:04 PM In reply to

    • mwelych
    • Top 75 Contributor
    • Joined on Fri, Apr 25 2008
    • Mint Hill, NC
    • Posts 802

    Re: Squealing noise during HARD acceleration

     

    When you did the clutch, was a new bearing a part of the rebuild? Throwoutbearing? Although if it were a throwout bearing, it would do it in all gears. It is difficult to find a noise while hauling down the road, Just tossing out an idea or two. Good luck bro...

     

  • Sat, May 7 2011 7:18 PM In reply to

    Re: Squealing noise during HARD acceleration

    I really appreciate the ideas Bro but, the clutch bearing and throw-out were checked and ruled out. The squeal is so loud that I would swear its coming from the tank. I'm thinking about getting one of those "chassis ear" devices that allow you to record noises from several different remotely mounted microphones ( which are numbered within the recorder ) to see if I can tell where the noise is originating from.

    HELLO OFFICER, PUT IT ON MY TAB !

  • Sun, May 8 2011 7:42 AM In reply to

    • lesty
    • Top 500 Contributor
    • Joined on Fri, Mar 5 2010
    • Posts 156

    Re: Squealing noise during HARD acceleration

    As soon as I read your post I thought about fuel pump.  Keeping in mind I know nothing about how HD fuel pumps work...Could you somehow remove it and get it spinning as fast as it would be in 4-5-6 gear?  That would tell you if it was the pump.  Could a drive belt be rubbing on something?  Does it only happen in certain gears...RPM's...road speed:  if you are doing say 60mph and you hear the noise...if you pull in the clutch would the noise still be there or does it go away?  What about an exhaust leak?

    Keep em coming,

    L

  • Sun, May 8 2011 9:11 AM In reply to

    • FX
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    Re: Squealing noise during HARD acceleration

    J,

     Okay, I'm probably gonna get myself in trouble here. but get that ATF the hell out of that primary. Although some clutch manufacturers recommend it, it is just plain no good for the primary chain, and may cause problems. ATF will make the clutches grab faster, but are you drag racing the bike?. Do you tear down. and check everything after every run? I don't think so. I would recommend regular primary oil...............The noise is not the fuel pump. That runs at a constant speed..........Noises are very hard to find, as you know. There is echo involved...........Since the noise comes on under load when hot, it could possibly be the Baker. What oil are you running in it? Regardless of Bakers recommendation, I  would try Bel Ray 85/140 (they have it here). Many of us use it, and are quite satisfied with it. If it is the transmission, the damage may have already been done with the bigger engine and harder pull. if you go to the Bel Ray and or primary oil, and the noise goes away, or lessons, then there's the problem. There is less strain on the transmission bearings/bushings at no pull, and lower gears when accelerating. That may be why you're only hearing it in the higher gears............I don't think it's the engine.................

    FX

    Don't force it, get a bigger hammer.

  • Sun, May 8 2011 9:42 AM In reply to

    Re: Squealing noise during HARD acceleration

    L., I am thinking about looking for a pump ( or tank with a pump ) on Ebay and trying that. Another idea that I had was the "electronic chassis ear" to try to pinpoint the source of the noise ... Is it really coming from my tank or, is the noise being transmitted through the engine ? The answer to those questions would lead me right to the problem I'm sure.

    For all the wrenching I have done on my sleds over the years, I've never removed a H-D fuel pump -- not to say that I didn't try --and it was a pain in the ass to say the least ( I never did get it out ). I THINK that the electric fuel pump is a "plunger" type of pump ( I don't know for certain ) meaning that the pump action is "up and down" vs. "spinning". If this assumption is true then the thought of it being the pump is a possibility, I suppose, based on the "pulsating squeal" frequency ( that is to say that the noise is not a steady tone but more of a pulsating tone ).

    As for the drive belt -- that has been suspected and checked and rechecked several times. Belt tension and alignment have been checked and verified as properly adjusted.

    Now, WHEN I hear the noise and under what conditions will almost automatically make you think it's the clutch -- If I rev the engine in Neutral, there is no squeal. I have tried to accel hard in lower gears ( 1, 2 and 3 ) and do not think that the noise is there when I do. Here is a scenario that will hopefully give everyone a better understanding of when the noise occurs:

    I have left the house after allowing the engine to reach operating temperature. A few miles through my subdivision and secondary roads to I-95. A moderate acceleration down the ramp, as I approach the merge I am in 5th  gear at around 60 mph and am faced with the choice of HARD acceleration to merge with traffic travelling 75 - 80 mph or, continue on the accel lane to a gradual merge. If I choose ( and I usually do ) to grab a handful of throttle ( 30 % throttle to 75 % throttle all at once ), the squeal starts and continues as long as my throttle position is over 75 %. It doesn't matter what speed I am travelling, what my engine rpms are or what gear I am in ( although I have mainly heard the noise in 4, 5 and 6 ). Now, I have wondered; Is it relative to "high engine load at lower rpms" or is it related to "throttle position: so, instead of cranking the throttle wide open, I tried a slow, steady roll on in 4 and 5th gear while on secondary roads and found that the noise occurs as my throttle position exceeds about 75 % -- roll off the throttle and the squeal stops, roll back on and the squeal returns. Disengaging the clutch is the same as trying to duplicate the noise in neutral -- no noise. So again, you would think it's in the clutch of tranny or final drive but, at the same time that you are removing the drivetrain from the equation, you are also removing engine load and fuel requirements.

    During my last attempt at resolving the noise, I pulled the top end apart, inspected the cylinders, rings, pistons, valves and S&S electric compression releases. Not convinced that the compression releases weren't leaking, I removed them and plugged the ports. The cylinder heads were shaved .020" to increase compression slightly and ensure that the heads were flat. Copper head gaskets were used during reassembly with Copper Seal. Valves were reated and new stem seals were installed. I changed the lifters ( which I wanted to do anyways ) to Jims PowerGlide hydrosolids and tapered adjustable pushrods. new intake gaskets and exhaust gaskets were also installed during reassembly.

    I appreciate the ideas L. -- Eventually, I'm sure I'll find it -- and, as ridiculous as the idea sounds, I need to rule out the tank, pump and dash somehow. The idea doesn't sound AS ridiculous since someone else also thought that it was a possibility as well -- Thanks !

    Jcal

    HELLO OFFICER, PUT IT ON MY TAB !

  • Sun, May 8 2011 10:09 AM In reply to

    Re: Squealing noise during HARD acceleration

    FX ! What's happening Bro ? I expected that I would hear from you again on this ( as you helped me out with it before ). I know that the primary oil issue is contradictory to everything we have ever done before but, I have to say that when I was running 20w50 in the primary, the Scorpion clutch was impossible to adjust -- if I adjusted it so that the clutch would disengage fully when I needed it to ( like sitting at a traffic light ), it would slip its ass off after it got hot. If I adjusted it so it wouldn't slip, I could never get neutral and the bike would continue to pull while sitting at a light ( I HAD to keep my front brake applied to hold the bike still ). I contacted Barnett Tech support about this and Pat ( Barnett Senior Tech ) first asked what oil I was using -- When I told him, he advised me to remove the clutch pack, clean everything, and scuff all friction plates and steels with a Scotch Brite pad, soak in a good ATF ( he specified Trick Shift, but emphasized that any GOOD ATF would be fine ) and refill the primary using ATF. I'm kinda caught between what I know -- or thought was right ( 20w50 in the primary ) and being unable to properly adjust the clutch and what I am told is right ( by Barnett ) to use ATF and everything adjusts and operates perfectly -- no grab, no slipping, no problems finding neutral and the smoothest shifting I have EVER had since the addition of the Barnett clutch.

    For the trans, I use what Baker recommends -- 75w90 synthetic. The conversion to the Timken bearing in the left side engine case was primarily to give better side load capacity in the engine. One more thing ...last year, I took the bike to the local dealer who was offering free dyno passes ( as a service sales tactic ) so, I thought, I would run the bike on the dyno and try to duplicate the noise there where I could stand next to the bike and hear where the noise was coming from. Well, it was only a 2nd gear roll-on and there was no noise. Again, this is a low gear run but, just another fact that I keep thinking about. I'm goind to try the heavier gear oil in the trans and see what that does, if anything -- I'll let you know, Thanks FX !

    HELLO OFFICER, PUT IT ON MY TAB !

  • Sun, May 8 2011 10:20 AM In reply to

    • FX
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    Re: Squealing noise during HARD acceleration

    J,

     Real long shot here. The fact that the noise comes on in higher gears may not be mechanically related at all, but speed related. If you say the noise seems to come from the gas tank, the air intake is right there, and might be the culprit............Try a run without the air cleaner. I've heard Hyper Chargers can make noise, and by the way, they don't work................I believe the fuel pump is a rotary pump, as in automotive.

    FX

    Don't force it, get a bigger hammer.

  • Sun, May 8 2011 7:01 PM In reply to

    Re: Squealing noise during HARD acceleration

    FX, long-shot or not, its an idea I hadn't thought of before. I DID check and replace the intake gaskets but never really gave any thought to a leak between the inlet and the intake ramps .... hmmmm, you might be onto something there but, one question about the scenario ( help me make it make sense ) ... If it was a leak, wouldn't it be worse during closed throttle ( when the butterfly is closed ) ? I will pull the air filter off tomorrow and take it for a ride. If the squeal gets louder or goes away completely then I will know for certain that the problem is in the intake somewhere. Thanks again Fx.

    HELLO OFFICER, PUT IT ON MY TAB !

  • Mon, May 9 2011 7:57 AM In reply to

    • FX
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    Re: Squealing noise during HARD acceleration

    J,

     Do'n good Bro...............The reason I don't like ATF in the primary is mainly because of the chain. Would you lube a rear chain with it? then why would you use it to lube the primary chain? Also, the very thin ATF may be bad for bearings/bushings...very little film strength. I just put a set of Barnett's extra plate in a Bros Dyna wide glide. Barnett recommends ATF, as we know. I put regular primary oil in it, and operation is fine in all aspects...........Have you tried 'primary oil'?........As you probably know, it's formulated for best service to the chain bearings, and clutches...........You're right, vacuum would be greater with no load. That's not what I meant. I meant a whistling type screech by the air passing through the air cleaner element.................Heres something else to consider. A failed rear wheel bearing under load and with the extra weight of acceleration can cause such a noise. I mentioned 'echo' before. A noise from the rear can echo within the fender/frame/gas tank, and give the impression of the noise coming from the gas tank, especially if you're running a windshield............Good luck, keep us posted............

    FX

    Don't force it, get a bigger hammer.

  • Mon, May 9 2011 9:01 AM In reply to

    • Ironhead
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    Re: Squealing noise during HARD acceleration

    J - is there a different dyno shop that has a rear-wheel dyno that you could put the bike on and try to re-create the noise? 

    The first tool out of the box should be the "book"  Geeked

  • Thu, May 19 2011 7:34 AM In reply to

    Re: Squealing noise during HARD acceleration

    FX:

    J,

     Okay, I'm probably gonna get myself in trouble here. but get that ATF the hell out of that primary. Although some clutch manufacturers recommend it, it is just plain no good for the primary chain, and may cause problems. ATF will make the clutches grab faster, but are you drag racing the bike?. Do you tear down. and check everything after every run? I don't think so. I would recommend regular primary oil...............The noise is not the fuel pump. That runs at a constant speed..........Noises are very hard to find, as you know. There is echo involved...........Since the noise comes on under load when hot, it could possibly be the Baker. What oil are you running in it? Regardless of Bakers recommendation, I  would try Bel Ray 85/140 (they have it here). Many of us use it, and are quite satisfied with it. If it is the transmission, the damage may have already been done with the bigger engine and harder pull. if you go to the Bel Ray and or primary oil, and the noise goes away, or lessons, then there's the problem. There is less strain on the transmission bearings/bushings at no pull, and lower gears when accelerating. That may be why you're only hearing it in the higher gears............I don't think it's the engine.................

    FX, you still on the anti ATF band wagon?

    The stuff works good and is perfect for a chain case.

    The object of a wet clutch is to be able to function,,,, wet.

    The ATF is perfect for the primary chain.

    It's the clutch, or the tranny; look there for the problem.

    Nowhereman.....who else?

  • Thu, May 19 2011 9:05 AM In reply to

    • Henry
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    • Joined on Tue, Jan 21 2003
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    Re: Squealing noise during HARD acceleration

     With you Nowhereman,ATF used in many apps.Like chain driven transfer cases,tremec transmissions all have gears,roller bearings,sun and planetary gears are you paying attention FX

     

  • Thu, May 19 2011 9:50 AM In reply to

    • FX
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    Re: Squealing noise during HARD acceleration

    I mainly don't think the ATF is good for the primary chain. Would you lube a rear chain with it? I can see a 50/50 mix, maybe.........pay me now, or pay me later...............Old die hards die hard, I guess..............Cool

    henedjer, Those boxes of which you speak if designed to run on ATF, would be fine, Harleys are not..............In my humble opinion................. What do ya think Harley would say if you took a bike back to them on warranty with a primary problem, with automatic transmission fluid in there?...................I'll shut up now, and not mention this again..............

     

     

    FX

    Don't force it, get a bigger hammer.

  • Fri, May 20 2011 8:09 AM In reply to

    • Henry
    • Top 200 Contributor
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    • Joined on Tue, Jan 21 2003
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    • Posts 256

    Re: Squealing noise during HARD acceleration

     The rear chain is not in a constant oil bath just a drip now and then,I don't thing any bearing manufacturers specifically design bearings for ATF, Take my bike back to the dealer,PLEASE bought new ones every year since '99 modify 'em immediately F@##@ Harleys warranty they don't cover anything but their own asses.and on your last comment you know what opinions are like.                   btw still hasve two old shovels been runnig ATF inthe old girls and the mew ones over 40 yrs.

     

     

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