1995 Sporster 883xlh big bore 1200
15k orginal miles
800 rebuilt miles


I just recently got my bike back from the shop I had a big bore kit installed in it to push her to 1200. I noticed what I thought to be a small exhaust leak coming out of the front head when me and a buddy was riding. We decided to head back to his garage to fix the problem..... In route to asses the problem I blew my rear head gasket..... So I purchased a head gasket and base gasket with an exhaust gasket... Tore her down and replaced the rear head/base gasket... Put her back together and installed the exhaust gasket on the front head... All is dandy right??? WRONG.... I started her up to hear the same damn "Exhaust leak" come to find out the front head gasket is semi blown right below the exhaust..............

My question is, Is the mechanic completly to blame for bad installation possibly improper tourqe, cheesy gasket set or can thier be something more complex causing both to blow out basically together.....

I do ride my bike hard as hell, Its constantly wrapped out and pushing 100-120 mph ..... Am I the cause? Regardless, I think I should be able to give her hell , if I cant I need a different bike

ide appreciate any comments / advice on the topic.

Thank You
-Zach

 

Are you using cometic gaskets? They require a different torque sequence than the stock type gaskets.

 

Take it back make him make it right

 

The gaskets that were in it are uknown they looked like metal with raised bumps in them.

The gaskets im putting in it now are James..

I'm conviced the torque was wrong the mechanic said he did the factory standard 8-14 ft lb with a 90 , On my rear I followed the James spec stopping at 42 ft lb. I plan on doing the same on the front.

 

How much warm up time are you giving the bike before you take off on it, chad

 

in the mornings at 4am on the way to work I usually start and go so I dont wake the neighbors..... Normally only about 1-2minutes.

 

On evos, they should be warm to the touch, I also don't follow recommended torque procedures because of failed head gaskets in the past, instead of using 42 ftlbs, I use 55, and I have never ever pulled a head stud yet, and with 55lbs and cometic gaskets, I have yet to see a head gasket failure, even on my bagger which is 10.75 to 1 , good luck, chad

 

We check the over all length of the studs case to tip and inspect the shoulders for gaps between the case and collar. If the mechanic used Harley specs you should be close to 42 ft. lbs. Which is what we use, we use motor oil under shoulder of bolt heads and on threads and retorque after 1/2 hour before installing rocker boxes.

 

The 90 degree method should not be used with MLS gaskets. Use the oil as KOC recommended and use the 9-15-35 and final of 42 ft lbs and recheck again as King stated before installing rocker boxes.