Base Gaskets

[maineultraclassic]

My buddy is in the middle of a rebuild on his '96 Fatboy with an 80" Evo. I've heard that the stock base gaskets aren't the best to use, so my question is this -

What are the best base gaskets to use ?

Cometic?

Thanks,

Steve

[fxr4mikey]

you might check out this thread, in this forum, Tim has done an outstanding job gathering all this data

http://harleytechtalk.net/htt/index.php?topic=2238.msg19830#msg19830

[still_havinfun]

I had the James Steel CylinderBase Gaskets PN# JGI-16777-94 on my old 89 evo for 40K before redoing everything at 100K. there was no evidence of any weeping with those gaskets and no goop was addd to the surface. At the 100K thing i reinstlled the same base gaskets and they are still staying dry after 25K more.

[ClassicRider2002]

"......My buddy is in the middle of a rebuild on his '96 Fatboy with an 80" Evo. I've heard that the stock base gaskets aren't the best to use, so my question is this -

What are the best base gaskets to use ?....."


Thanks, Mikey.....

Mainultraclassic....glad to help you a long time ago you spent some time helping me with my 2002 RKC when it came to trying to understand the "merits" of a SuperTrap 2-1 SuperMeg exhaust system......


SO HERE IS A FEW "LINKS" TO THREADS YOU MIGHT FIND HELPFUL....even though the "catagory of description is for an FXR model evo bike.....the ENGINE aspects are the same.....so here you go:

FXR EVO ENGINE DISCUSSIONS:

• 1999 FXR2 ROCKER BOXES REPAIR HELP
• 1999 FXR2 OIL IS EVERYWHERE ANY IDEAS? ? ? ? ?
• JAMES GASKETS THREE THUMBS UP
• EVO BASE GASKETS
• BASE GASKET WEEPING
• ROCKER BOX GASKETS~FXR*

*Within the above attached THREAD I am "FXR2evo99". 
                 There are a total of 43 posted "REPLYS" into this THREAD, and basically starting at "REPLY" #23 begins
                 where you will find the most interest. "REPLYS" #23 - 31 are the most informative for any EVO ENGINE. 
                 Some of the information within this "THREAD" will relate to working within the "frame" of the FXR butttttttttt
                 "REPLYS" #23 - 31 will be "UNIVERSAL" to the application of any EVO ENGINE .  This "THREAD" also shows
                 photos of the actual gaskets and part numbers that I have used on my EVO ENGINE [99' FXR2] which have been
                 successful.

Regards,

"Classic"

[maineultraclassic]

We just removed the cylinders yesterday so he could start removing the stock gaskets that were bonded to them. He had some weeping starting around the base gaskets, and that was only at 25000 miles.

He was going to go with a new pair of stock HD gaskets as he picked up a HD top-end gasket kit on Friday.

Steve

[maineultraclassic]

If I changed brands on the base gaskets, that would effect my deck height. With the stock gaskets in there, he was at 0 deck height on both cylinders, so I would hate to go to a slightly thicker base gasket and drop the piston down in the cylinder a bit.

I think he's going to stick wit the stock gaskets, he's in the process now of cleaning off the old gaskets from the cases..........man those things can bond good.

Steve

[dave_9113]

Steve,

You can get Cometic or James "stock" dimension gaskets, but nevertheless, the H-D gaskets will work too.  If it's paper, then you want to dress it with hylomar or gasket cement as an added measure.  If you really want to cure the base gasket, get the Hayden Oil fix or the pigtail type oil fix.  I still recommend the James gasket myself. 

Bottomline is warm up procedures prior to riding will eliminate the chances of base gasket weep/leak.  I'm assuming that  your cylinder base is straight and all that.  Good luck.

dave

[Hybredhog]

    The quick way to clean off the base gasket material from the cylinder & level off the surface is to use a leathe. The gasket surface is usually warped a bit anyways, and you only need to take .002-.005 off, just be sure to check piston deck hieght afterwards & use the appropiete thickeness of head gasket, 8 out of 10 times you can still use a .030 cometic MLS type & I believe the rubber coated metal type base gaskets are best...Jeff

[springer-]

Hi Steve, this might help though not a direct answer to your question. http://www.bigboyzheadporting.com/showthread.php?t=76

[JohnS_Rosamond]

I haven't seen the "latest" set of HD gaskets for the cylinder base, but if they're paper, I really wouldn't suggest you use those.  The theory that my buddy and I came up with is that weeping is due to crank case pressure that comes up from the spigot, and not a "slow weep from the drain hole."  Therefore paper wouldn't be the best thing to combat pressure.  Also, as you've seen, they can be a bear to get off.  The metal base gaskets (which I highly recommend) don't get soggy, they expand with the heat of the engine, and they are not so thick that they have much effect of compression or deck height.

[ClassicRider2002]

I haven't seen the "latest" set of HD gaskets for the cylinder base, but if they're paper, I really wouldn't suggest you use those.  The theory that my buddy and I came up with is that weeping is due to crank case pressure that comes up from the spigot, and not a "slow weep from the drain hole."  Therefore paper wouldn't be the best thing to combat pressure.  Also, as you've seen, they can be a bear to get off.  The metal base gaskets (which I highly recommend) don't get soggy, they expand with the heat of the engine, and they are not so thick that they have much effect of compression or deck height.

That.....my boys is the MAN!!!!......and he has spoken......

AWESOME John!!!!!

Regards,

"Classic"

[maineultraclassic]

Hi Steve, this might help though not a direct answer to your question. http://www.bigboyzheadporting.com/showthread.php?t=76

George,

That will take care of the cylinders, but what if the cases are not flat?

Would Cometic base gaskets be better since they are MLS?

Bean mentioned the lapping plate idea when we were up there last week, we might have to pick it up when we pick up the heads. We could use it on the cylinders, then ship it back up to Bean after.

Steve