Piston slap at 30,000 miles?

[Hoople]

I guess this would be a good time to do a 95" kit.

Don't just install a kit and ride off happy. This happened over the last 25K miles for a reason. The old parts are yours to keep. Mark the parts and inspect them after they have been replaced. It doesn't take a 1/2 million dollar machine shop to make some quick measurements especially when you can compare the "bad" (rear) to the "good" (front). Try to understand what took place and why it happened.

With the engine noise being as bad as you describe, you should be able to insert the piston into the bore (without rings) and see the excessive play. The allowable numbers are listed in the service manual. I also would check the oil pressure now and after the job was completed.

 

[corrigon]

In 1989 we bought a new ultra with the plans of making an Alaska tour we had wanted to do. I wanted at least a 1000 miles before the trip. Right off the bat I heard this noise and having worked as a mechanic my whole career figured piston slap. Harley dealer checked and agreed. Harley factory said bull. So I contacted the factory myself and informed the guy that if this thing self distructed in the middle of the Yukon I wanted it on the record I had notified them. He said I was right that it was piston slap and the reason was because of the way the pistons were shaped so that they would conform to the bore after so many miles. A classic example of a line of (EDIT) in order to get out of warranty work. Anyhow I had a record so if it left us sitting on the Alcan highway it would be on them. We sold it in a little less than 20,000 miles and it was still rattleing away. It would take about 30 miles riding to start the noise and then stay about the same from there on. On the project bike I am on now the back piston has defintely been slapping but I don't know the mileage on it. Not a fun thing to put up with but I wish you luck in trying to get them to do anything about it.

Please read this...

HDTimeline Language Policy - Harley Davidson Community

 

[GARVIN]

have been a tech for over 35 years & could have swore my 09 ultra had piston slap . after many they all do it from different dealers I replaced lifters & push rods (adjustable) - the engine has gone to a slight ticking from hard knocking , at times it sounds like rocker are being pushed sideways under load - i`ll deal with that over the winter

 

[dolt]

Based on your description of the noise; not noisy cold but noisy when it warms up; still not buying the noise is piston slap. The only way you will know will be to have the tech bolt the cylinder up in torque plates and check piston to cylinder fitment before proceeding with a big bore solution. Piston slap with OEM pistons and cylnders with 39K miles is rare if proper maintenance has been performed and the motor not abused.

 

[HDSickness]

Ok so I have decided to do a 95" bore and new forged pistons.
While they are in there anything else I should have done? I was hoping with proper maintainence This bike would last me many many miles like maybe 100,000 but all the techs I talk with laugh when I say that.
Thoughts? Oh and what kind of performance gains would I see with a 95" kit?

 

[HDSickness]

Don't just install a kit and ride off happy. This happened over the last 25K miles for a reason. The old parts are yours to keep. Mark the parts and inspect them after they have been replaced. It doesn't take a 1/2 million dollar machine shop to make some quick measurements especially when you can compare the "bad" (rear) to the "good" (front). Try to understand what took place and why it happened.

With the engine noise being as bad as you describe, you should be able to insert the piston into the bore (without rings) and see the excessive play. The allowable numbers are listed in the service manual. I also would check the oil pressure now and after the job was completed.

Possible I got a bad motor from factory? I took great care of this bike since I bought it syn oil every 3-4k. and did not race or abuse her.

 

[dolt]

Ok so I have decided to do a 95" bore and new forged pistons. While they are in there anything else I should have done? I was hoping with proper maintainence This bike would last me many many miles like maybe 100,000 but all the techs I talk with laugh when I say that.
Thoughts? Oh and what kind of performance gains would I see with a 95" kit?

No need for forged pistons; they will get noisy with mileage. The cast SE flat tops will work just fine and can be setup at .0006" to .0015" while forged have to be setup at .002" to .004" depending on piston manufacture.

The Samson pipes are not known for the power they make. With a better exhaust, .030" head gasket to boost compression and a good tune, you could see 90TQ/80HP (round numbers).

 

[HDSickness]

Ok my guy suggests forged, better I do not know.
I should go with Rinehart true duals and do it right? do not want 2-1 set up I know that is best but like the look an don't want falsie.
I want it done right for longevity I do alot of long rides and reliability is key.
Not really looking for huge gains in hp or tq, happy with performance.

 

[dolt]

Ok my guy suggests forged, better I do not know.
I should go with Rinehart true duals and do it right? do not want 2-1 set up I know that is best but like the look an don't want falsie. I want it done right for longevity I do alot of long rides and reliability is key. Not really looking for huge gains in hp or tq, happy with performance.

Forged will work, just get used to hearing the pistons rattle until the motor reaches operating temperature. I love cast pistons becuase they are quiet and will use them unless working with a bore and no cast are available.

I understand that you are "not really looking for huge gains......." but if you are going to invest in a 95" package, why not optimize the performance of the package? If you are "happy" with the performance, keep the Samsons. :small3d031:

IMHO, RH TDs are not a good fit for motors smaller than 107"; soft on the bottom and often have TQ dip between 2500-3000. However, a lot of 95" guys run them. I run them on my 107" and, truthfully, believe they are costing me some low end TQ. I am considering re-baffling.

A tuner/builder in my area tunes for four dealerships. He is seeing good results with the V&H Power Dual head pipe paired with OEM mufflers that have been re-baffled with Fullsac power core baffles. The Fule Moto head pipe with their Jackpot mufflers makes good power. I think if I was going the TD route again on my 107", I would give the V&H Power Duals a try.:bigsmiley12:

Don't forget to tell your guy to use a .030" head gasket; it will add .25 points to your static CR; compression = torque.:cheers