[ZTFerrari]

Howdy,

I seem to have blown a horizontal head gasket; the gasket leaking to the point of almost spraying out in-between the multilayer head gasket.

My question is, how difficult of a job is it to swap head gaskets? I would consider myself a comparatively competent mechanic but it seems there are some special tools required in order to get at the head stud nuts?

Also, what type of gasket is suppose to be used on this? It seems there is a different type of contraction between the vertical and horizontal head gaskets. The horiztonal is sandwich type made up of 4 different layers where the vertical looks to be one thicker steel gasket. I am curious if the bike has had some mechanical problems in the past.

Regards,

Scott

[Spudd]

The Gaskets on both Heads are exactly the same. The Base Gasket is simple and different. The Head Gaskets are 125$ ea.

Remove Tank, airbox. spark plugs, Radiator(drain first), Drain Oil, remove Oil Cooler. Set Horizontal Cyl at TDC. You can shift the bikenin to 6 th gear and rotate the rear wheel to set the Timing Mark. Markmyour Cam Belts using paint or a bright marker. The Cam Shafts have a notch that lines up horizontal on the Horizontal Cylinder and at 45 degrees on the Vert. cyl. Just mark your Belts to match up with the line created by the Valve Cover. Remember to replace the Belts exactly as you removed them. In your case you only need to remove the H Cyl. Belt.

Clean everything up on the two mating surfaces, also the Piston Head can be cleaned. Take care in doing this. Be watchful of the gasket Locating Dowells. When you reinstall the new Gasket, the Dowells should be fitted on to the Cylinder surface. It can be helpful to have a second hand when refitting the Head in order to fit Gasket. There are stamped numbers on one side of the Gasket; this side should be up or facing the Head.

Since you are doing the H Head you don't need a special Head Nut wrench, but you will need a torque wrench. You can attach the torque wrench to the box end of the 14 MM wrench. This will add about 5 inches to the length of your TW. The Torque adjusting formula is...

Find required Torque. In this case, they want you to tighten in 3 steps, remember to use the X pattern slowly...

Step 1 -20nm
Step 2- 40nm
Step 3- 60nm

To convert to Ft/lbs.....NM x .738 = ft/lbs

To convert to proper torque using a Crows Foot( extension)

Length of Torque Wrench x required torque divided by combined length of TW and Crows foot.

For example: 15 in. Torque Wrench x 44 ft/lbs divided by 20 combined inches = 33 ft/lbs.

This is probably the most critical part of the whole operation.

Also, since you have the Head off, you just as well check the Valve clearances.

A little long winded, but I'm trying to help.

TAKE YOUR TIME

[ZTFerrari]

Spud, you are a scholar and a gentleman. Thank you for that informative response.

I will be tearing into it soon. I'll let you know what I find.

[ZTFerrari]

I tore down the bike - the cause of the leak was a snapped head stud!?!

one of the head studs snapped right above the threaded part which goes into the crankcase. Luckily, I was able to get it out.

Is this common? what is the cause of this? the bike has 6k miles on it

[ELTWIN]

The stud must have had a flaw in it to fail like that. Only heard of it happening one other time on a Duke and that was on a bevel. Thankfully it's an easy fix for you.

[Spudd]

Like I said previously, the torque on the Head Nuts is critical. How did you remove the broken Stud?

[ZTFerrari]

The stud was removed with a vice-grip and a few curse words.

I have ordered new (4) studs. Should be an easy fix. I'll keep everyone posted on my progress

[Spudd]

Well, now it will be the right way, for sure!
Good luck