Head torque specs

J

JE

Guest
I just got done putting the first 50 miles on my Whizzer and noticed the head is leaking a tiny bit.Bill re torqued the head after shaving it and reinstalling it. It's got the copper head gasket and proper washers under the bolts.I just need to find out the proper sequence and inch pounds of torque to use.
 

MoonKS

Member
Joined
Apr 4, 2008
Messages
170
Hi JE,

I don't have any sequence info - but Quenton said in my Break-In thread for my 2007 NE5:

"The torque specs for the 8 MM head bolts is 175 to 180 INCH pounds, and the 10 MM bolts should be torqued to 210 INCH pounds"
 

Quenton Guenther

Well-Known Member
Vendor
Joined
Aug 2, 2007
Messages
2,156
Hi JE,

Start with the large 10 MM bolt near the spark plug, go directly across to the other 10 MM bolt, then across and forward to the 8 MM bolt, then back to the oposite side, next tighten the rear corner 8 MM bolt [behind the spark plug], then straight across to the opposite corner [nearest intake port], then all the way forward to the 8 MM bolt at the front [flywheel side], then across to the 8 MM bolt in the front [sidecover side], then lastly the rear center 8 MM bolt. Start at 140 inch pounds, then 160 inch pounds, then 175 to 180 inch pounds, and finish with the two 10 MM bolts at 210 inch pounds. A few words of caution, many if not most, cylinders don't have the same depth of threads in all holes. If the head was milled, it is possible the bolts are too long and "bottoming out". If the 8 MM head bolts still have the small thin washer attached, you might want to remove them [a simple pair of wire cutters will work]. The large 10 MM bolts don't have any washers under them, I usually make a set when I re-work my motors. Never tighten the head bolts while the motor is hot. If you are using 2 washers on each head bolt, remember, I don't.

Have fun,
Quenton
 

Sean Durham

New Member
Joined
Mar 6, 2016
Messages
5
Hi JE,

I don't have any sequence info - but Quenton said in my Break-In thread for my 2007 NE5:

"The torque specs for the 8 MM head bolts is 175 to 180 INCH pounds, and the 10 MM bolts should be torqued to 210 INCH pounds"


that figure is wrong. I tried torquing my head bolts to your numbers and stripped the cylinder.
 

Quenton Guenther

Well-Known Member
Vendor
Joined
Aug 2, 2007
Messages
2,156
that figure is wrong. I tried torquing my head bolts to your numbers and stripped the cylinder.
The numbers are correct! The NE 8MM bolts 180 to 190 INCH pounds. The 10 MM 210 INCH pounds.

The WC-1 cylinders use smaller 6 MM bolts and 95 to 100 INCH pounds torque.

If you stripped the bolts either your torque wrench is broken or the threads were all ready in trouble.

I have rebuild or upgraded hundreds of these motors and have used the torque numbers mentioned above for over 10 years.

Be sure to replace thin head bolt washers for THICK washer to stop head bolts from always working loose.

Have fun,
 

Sean Durham

New Member
Joined
Mar 6, 2016
Messages
5
Hi JE,

Start with the large 10 MM bolt near the spark plug, go directly across to the other 10 MM bolt, then across and forward to the 8 MM bolt, then back to the oposite side, next tighten the rear corner 8 MM bolt [behind the spark plug], then straight across to the opposite corner [nearest intake port], then all the way forward to the 8 MM bolt at the front [flywheel side], then across to the 8 MM bolt in the front [sidecover side], then lastly the rear center 8 MM bolt. Start at 140 inch pounds, then 160 inch pounds, then 175 to 180 inch pounds, and finish with the two 10 MM bolts at 210 inch pounds. A few words of caution, many if not most, cylinders don't have the same depth of threads in all holes. If the head was milled, it is possible the bolts are too long and "bottoming out". If the 8 MM head bolts still have the small thin washer attached, you might want to remove them [a simple pair of wire cutters will work]. The large 10 MM bolts don't have any washers under them, I usually make a set when I re-work my motors. Never tighten the head bolts while the motor is hot. If you are using 2 washers on each head bolt, remember, I don't.

Have fun,
Quenton

I appologize, the mistake was mine. I had the wc1 cylinder, I decided to upgrade to a ceramic cylinder since I'm attempting to modify my pacemaker ii to a decent performance bike.
 

Quenton Guenther

Well-Known Member
Vendor
Joined
Aug 2, 2007
Messages
2,156
I appologize, the mistake was mine. I had the wc1 cylinder, I decided to upgrade to a ceramic cylinder since I'm attempting to modify my pacemaker ii to a decent performance bike.


Just to let everyone know the latest cylinder isn't ceramic! More trash talk from Taiwan. The latest cylinder is an aluminum NE cylinder with ceramic paint, something I started doing in 2001. I used ceramic cylinder paint made by Dupli-Color and baked it on in an oven at 200 degrees for 2 hours. Black ceramic paint lowers the operating temp by over 50 degrees, of course Joe Lin isn't using black [yet], because he doesn't know black works best [yet].

Be sure to obtain thick head bolt washers for the 8MM bolts [can use vintage Whizzer 5/16" washers]. The two needed for the 10MM bolts must be made as there is very little room between the head and the bolts.

Have fun,
 

mason_man

Active Member
Joined
Jul 19, 2009
Messages
480
This ceramic coating is sprayed everywhere, exhaust port, intake port, top deck of cylinder.
Bead blast it all off if possible! the NE cylinders use to be 24mm intake valve, 22mm exhaust.
This one is 22mm and 22mm why?
and now there dropping in a 24mm intake valve but leaving a 22mm valve seat, why?
Not that you can't still upgrade this one. Intake port is just a little bit bigger than the WC-1'S intake port. you can also move the piston all the way to the top.

Ray
20150808_142656.jpg
20160225_195638.jpg
20160225_195648.jpg
20160225_195656.jpg
20160225_195714.jpg
20160303_182328.jpg
20160303_183044.jpg
20160303_183537.jpg
20160303_183627.jpg
20160417_175330.jpg
20160303_183537.jpg
 

sbest

Active Member
Joined
Nov 1, 2015
Messages
170
Your pictures get me excited to do a flathead.

My lawnmowers all got porting, header, valve jobs and wedge planed heads over the years.
Just cuz I could! No stall in the heavy stuff!

Beauty.

Steve
 
Top