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-   -   Cracking head pipe (https://www.hdforums.com/forum/general-harley-davidson-chat/1208277-cracking-head-pipe.html)

ryda 11-19-2017 05:52 PM

Cracking head pipe
 
Hello,
Don't post often but kinda looking for cause of my exhaust pipe breakage up near the front head, I can get the pipes to last 1 to 2 years before they crack and break. I have tried multiple brands and styles same issue. Not sure if it is my riding style or my PCIII is running the front cylinder to lean causing extra heat at the header port.

FXDBI 2007, 96" with PCIII
80000+ miles
Ride daily all weather
Ride hard and tend to drag the pipe, I try not to but it happens.

Just lost another pipe today Python Throw Back

Any knowledgeable help appreciated, if it's my riding stye may have to buy a sport bike also.

monkeyboy22 11-19-2017 06:22 PM

Sounds to me that the pipes don't have enough support. All that weight, the leverage and vibrations cause head pipes to crack. Do you have any mounting brackets at the rear of the pipes. I believe on a dyna of that year the two pipes are "tied" together with bracket that has two "T" bolts for each pipe and also a bracket near the end of the pipes that attaches to the pipes and the frame of the bike.

ryda 11-19-2017 07:28 PM

Yea it has the two pipe bracket that attaches at the transmission, and nothing farther forward. I probably am just beating it against the street to often

Guess I will try shorter and higher.

halnwheels 11-19-2017 08:26 PM

Yeah, it's not normal for the pipe to crack. I got 84K miles out of my stock front pipe on my Ultra and when I needed to remove it, I replaced with a new one because it was thinning. No cracks though. The rear cracked once at the Y pipe and was replaced under ESP at maybe 40K miles. I replaced this one too because of thinning. I figured let me get it now while they're still available. The stealership didn't want to use then on my new longblock.

Slingshot383 11-20-2017 05:07 AM

Could be your motor mounts need replacing? If they are soft or worn out, they will allow the motor to move too much, causing bad things to happen.

GRWHD 11-20-2017 07:02 AM

I guess the first question would be who installed the pipes?
If it was you, were they under any preload at the time of installation?
If it was extreme heat you should have other issues as well...
So moving on to whats moving around and causing it (most likely)?
Mounts, motor, riding.
Unless you are putting allot of pressure on the exhaust when corning I would have to lean towards the mounting locations and what they attach to.
Like earlier stated how are your motor mounts front and rear?
If the exhaust mount to the frame is solid and the motor is moving around to much it will put constant strain on what ever is in the middle.

ryda 11-20-2017 06:50 PM

Didn't think about engine movement.....I will have to check the mounts and make sure they are good, although I haven't noticed any abnormal movement.

Thanks for the extra brain power...

ryda 12-04-2017 09:31 PM

4 Attachment(s)
Front mount was shot.....Thanks guys..

I ended up throwing on some Bassani Sweepers.....

TwiZted Biker 12-04-2017 09:43 PM

Two things will cause the issues you are having, stressed or misaligned parts or vibration. Can be royal bitch chasing down and correcting pipe breaking issues. Twinkies loose motor mounting design isn't doing you any favors in the exhaust rigidity mounting arena.


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