Cylinder Bolt Torque?

[eff]

OK, my piston kit is on the way and this is my first top-end on my GG.

The cylinder bolts are 13mm and 2 of them are under the power valve covers. I have the Motion Pro torque wrench adapter but it is 13mm. How do you get a socket in there to torque them up?

 

[GMP]

You don't. Use the additional length of the Motion-Pro wrench to calculate the new setting for your torque wrench. You may have to hit the outer edge of the wrench box section on a grinder to fit it over the two nuts under the PV covers.

 

[eff]

The motion pro wrench I have is only 12 mm and 14mm. The head bolts are 13mm??

 

[Brian VT]

I think the KTM "bottle opener" is 13mm. Maybe you could borrow one ?

 

[eff]

I was just looking for one. I was just looking at a crows foot set too.

 

[Loosenut]

Or you could do what I do. I just equally tighten all of the cylinder mounting nuts. In the past I would check the 2 easy to get to nuts with my torque wrench and usually nail them near the middle of the spec. This stems from a top-end change on my old 1987 CR125 at the event with only basic tools. I checked the bike after the race and only 1 head bolt was 2 ft/lbs under spec. The rest were near the middle of the spec.

 

[Brian VT]

I did mine by feel too and have had no problems (3 years).
Next time I'll get a proper tool.

 

[GMP]

Like Mike, I've done it by hand after getting a "feel" for what the torque is like with the 13mm box wrench. I've also used a combo wrench with a 13mm hex driver on the other side in the open end section, on the torque wrench. Crows foot won't fit.

Don't be surprised if a stud comes out of the cases. Clean everything up and red loctite it back in, using 2 13mm nuts jammed on the stud.

The most logical thing to do since you have the correct 12mm tool would be to find 12mm flange nuts, probably from a Jap bike.

 

[eff]

Thanks guys!

 

[LandRover]

I do mine by feel too......

 

[eff]

Looks like I'm going down that road too. I'm just waiting on my gaskets to come in. They forgot to ship them with the piston. OOPS. The good news is I'm in no rush and have not had the time.

 

[Brian VT]

The cylinder bolts are 13mm and 2 of them are under the power valve covers. I have the Motion Pro torque wrench adapter but it is not 13mm. How do you get a socket in there to torque them up?

I just noticed that a 1/2" socket drive fits nicely into the open end of a 13mm wrench !

 

[rpduc]

You guys probably know this already but if you can mount the wrench/extension at 90 degrees to the head of the torque wrench, no calculations are necessary.

I just noticed that a 1/2" socket drive fits nicely into the open end of a 13mm wrench !

Duh!! Never thought of that. Nice ahaaa moment.

I wonder how the "angles" of the open end and box end might figure into the equation. Probably not enough to worry about.

I had to make a similar tool for torquing the head bolts on my Duc. Same access issues. Just welded a socket onto a 3" chunk of a cheapo 13mm box end wrench.