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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
Hello. Bike is 2024 Tri glide, going to install S&S internal head breathers, can I remove top rocker cover without removing coolant lines, this is my first M8 that I have worked on Thanks for all replies.
Hello. Bike is 2024 Tri glide, going to install S&S internal head breathers, can I remove top rocker cover without removing coolant lines, this is my first M8 that I have worked on Thanks for all replies.
No- the lines physically block removal of the top rocker box. Pain in the ***, which is why (I believe) they went to the Gen 2 heads/cooling system on all 2026 models.
BTW, the stock breathers are perfectly adequate if the rest of the system is stock. I run stock breathers on my 2019 131" trike without issues.
Last edited by rigidthumper; Jan 2, 2026 at 09:36 AM.
Forget all that work, just replace the transmission top cover with the newest configuration cover, route the breather hose overboard.
Block the breathers using solid bolts.
About 90 bucks for the cover.
Vs the cost of a rocker box gasket set (About 100 bucks) and S&S breathers 300 bucks.... 300 bucks for breathers????
And about 4 hours+ work vs 30 minutes, and a lot of money.
I have 2 M8 machines that I have set up with the new transmission cover vented overboard, head breathers blocked off with solid bolts, I have not seen a drop of oil on the end of the breather hose.
Last edited by Dan89FLSTC; Jan 3, 2026 at 06:44 PM.
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M8 S&S Head Breathers
