Finned Headbolt Bridge

Part Number 43859-00


Finish / Color: Black



This exclusive aluminum Finned Headbolt Bridge covers both headbolts and the spark plug, filling out your cylinder fins all the way to the rocker box.

  • Features an engraved Bar & Shield emblem
  • Easy to install with unique headbolt mounts
  • Sold in pairs
  • Includes all necessary mounting hardware

Fits '99-'17 Twin Cam-equipped models with electronic fuel injection and '00-later FXSTD models.

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  • Model
  • Material Content

  • Warranty

    1 year limited warranty – Go to for full details
  • Sold in Unit

  • In The Box

    All necessary mounting hardware
Finned Headbolt Bridge is rated 4.7 out of 5 by 28.
Rated 5 out of 5 by from Totally Finished Look to Motor Bridge Looked great online so I thought I would splurge on the purchase. WOW - So worth the cost and gives the motor a very finished look by covering the motor bolts. Simple installation and high quality parts. I added the screaming eagle spark plug wires in orange and it really sets off a clean professional looking appearance. Highly recommended, you will not be disappointed.
Date published: 2017-11-25
Rated 4 out of 5 by from Quick easy stylish addition (beware the threadlocker) I really like the finished look it gives to my engine. Is really a pretty simple quick installation (in a perfect world). I docked 1 star because it would be nice if the instructions warned that the fasteners come with an epoxy like threadlocker on them. I sat in my livingroom and pre-threaded the plug screws and went out to my bike to install the bridges. Started to attempt to tighten the screws and found out they were already locking in place. I destroyed one allen wrench trying to back them out. I finally got them out and cleaned up and the installation finished. So what should have taken 15 mins max turned into about a hour.
Date published: 2017-09-01
Rated 5 out of 5 by from Makes the Engine Top End look Amazing!!! This just makes the engine have a more finished look! I have put these on every Harley I have owned because of the way they look! Great product!!! They are also very easy to install, maybe 15-20 minutes taking your time; directions are perfect. And boy how happy you will be with them on!!
Date published: 2017-08-12
Rated 5 out of 5 by from Spark plug covers These are easily installed and adds a little extra heat to dissipate from the engine. Mostly it add accent to the engine to make it look more complete.
Date published: 2017-07-14
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  • clientName_harleydavidson

Why this fits 15' FLHTKSE but not fits 15' FLHXSE? They engines are the same!

Asked by: cdemczuk

Once installed is there a heat build up that would be bad for the heads& spark plugs?

Asked by: Harleyrider50
Hello Harleyrider50, You do not need to worry about excessive heat build up from installing the covers. Thank You!
Answered by: JD34
Date published: 2015-04-15

Diamond Cut Edge?

Does these match up with the diamond cut edge on a stock 09 Ultra Classic?
Asked by: Curl58
Hey Curl58, Yes, this Finned Headbolt bridge will match the engine finish on your 2009 Ultra Classic.
Answered by: Wisco832
Date published: 2014-06-25
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    Prices listed are generally the Manufacturer's Suggested Retail Price (MSRP), excluding taxes and shipping. Prices at local dealerships may vary. All online orders will be fulfilled and shipped by
    Harley-Davidson Motor Company as the agent for the Selling Dealer.