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Discussion Starter #1
to keep the variator pulley from rotating when torquing down the center nut (105N*m , 76ft.lb), place a spare socket BEHIND the rear or movable pulley, lodged against one of the fins cast in the engine case, per picture included.

I am plenty miffed at Suzuki for
1) describing in the manual that holding the pulley to torque the nut requires accessing the crankshaft on the opposite side ( thats a LOT of work )
2) not casting into the outer /fixed face of the variator pulley some small bosses of pin holes for a typical sheave/ pin wrench / homemade to lock into.

I tried a strap wrench but it was awkward and kept slipping off.

If you are tempted to jam a bar or screwdriver into the fan fins on the outside pulley ( to lock the pulley against the bike frame or case) you risk breaking that fin off,
unbalancing the sheave and ruining an expensive part, as unhappy people have described elsewhere in this board.

You will however find, on the back side of the front pulley (variator or drive pulley) there are plenty of small bosses or edges to lodge a socket.
I used a 1/2" drive 14mm short socket as the correct height, but any size long enough length and small enough diameter to fit in the space will do.

I am NOT a fan of impact wrench torquing described else where, too much variation and definite risk to the nut and the crankshaft. My rule is NEVER use an air tool to TORQUE a nut.
I the only reason to impact it I guess is to avoid owning a torque wrench ( poor economy) or maybe to avoid holding the pulley against rotation while torquing, but to each his own.

Heck if you didnt want to buy either a (not very expensive or large) torque wrench on an impact tool, and you don't feel like scrapping an engine with your air tool, just torque it by hand - the required torque is just a good heave on a 1 or 2 foot long length bar. The longer the bar , the less the load. You can always get a feel for what 35 pounds feels like on a bathroom scale, and apply it to a bar two feet away from the nut (2 ft x 35 lb = 70 ft lb, right ?) for instance.... You shouldn't be too much off ... just snug that baby and leave the impact tool for LOOSENING nuts.

Holding the clutch bell is much simpler due to the many holes in it, a "pin wrench" comes in handy but at the very least a couple stout nails through a thin but sturdy wood board will let you hold the clutch bell / rear pulley against turning while torquing the certer nut (85 N*m, 62 ft.lb)


UN-TORQUING the nut was done with a pin wrench in the fan blades, at least the force was sread out onto two fins, but it loks like there is plenty of case fins and pulley bosses to use the same techniques facing the opposite way to prevent the pulley from turning counterclockwise.
sorry if this simple and common technique ( locking a pulley with a socket) was posted long ago, but my search only yielded reference to impact wrenches and broken fins. eww.

search key words; belt replacement , pulley torque , torquing , variator nut , moveable drive face, crankshaft lock , fixed drive face.

Remember - if you toot while on a scoot, you don't pollute, it's butt a salute !
 

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Really Suzuki.....why make us work so hard.
The parking brake also does the same thing if the belt is on....and no special tool or crank to access.
That socket idea is a good find if you have the belt off for sure though.
Thanks for the tip!
 

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Discussion Starter #3
yes the P brake holds the rear wheel and rear hub (clutch hub) for nut removal & replace.
Thanks, I already forgot that I learned that when I did the job yesterday. Getting old.

But the brake acting "through" the belt is not likely to hold the FRONT DRIVE pulley for nut torquing, seeing at the belt will probably slip.
Like for instance you just removed and are replacing the belt after variator service.

The socket-stopper is for front pulley.
appreciate the reply.
 

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It looks like an excellent tip. Thanks! I'll try it tonight.

I use an electric impact wrench because I couldn't see a way to hold the variator in place while torquing the nut. Like you, I tried a strap wrench and saw quickly that this was an excellent way to break a fin.

I would much prefer though to use my torque wrench and know what the torque is.

Chris
 

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Very innovative, not something I would have considered doing. My only comment is to keep in mind you are placing 320 to 340 lbs force¹ on the movable pulley boss, socket and crankcase rib--so make sure you get it solidly placed if using this method. You also what to use a long enough socket that it cannot possibly flip to its side and end up bursting through the crankcase wall or breaking the pulley--at 45° angle or better the thrust toward the pulley flange/crankcase wall would start to grow very rapidly.

¹ - 75 lb-ft = 75 * 12 = 900 lb-in. The variator pulley is 5.25" diameter, 2.6" radius; 900 in-lb / 2.6" = 345 lbs force.

====================================================
I use torque sticks and an air wrench:



(you need to hold the variator/clutch bell firmly with you other hand--I was pressing the camera remote here)
 

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cliffyk said:
I use torque sticks and an air wrench:
Torque sticks and an air impact wrench is my method also.
 

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Discussion Starter #7
I cant actually remember what the bosses on the back of the pulley even look like, but there was definitely enough lip to catch the socket without skating over it and in that shear mode, no way could I machine it off unintentionally.

The crankcase fin; eyeballing it's thickness, I would trust it to hold up me and a friend and maybe the whole bike over a canyon, if loaded slowly.
A very hearty hammer blow might be able to chip it off so I would use a cheater bar, slowly loaded, if the nut is hard to take off.

Whapping a wrench handle to get the nut started off
~could~
~maybe~
~sometimes~
~on a bad casting~
~at midnight Friday 13th~
~with recent evil kharma littering my wake~

bust that fin off.

I'd done this same sort of thing lots of times to get cam & crank nuts off of valve trains, or flywheel bolts, and have yet to leave a mark let alone a broke alloy casting.

but good warning and excellent calculations.
I did make sure to use a socket diameter that lodged far back in the recess to avoid loading up the lip/vanes very edge.
 

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I think what I might do tonight, is to tighten the nut like I always have done with an electric impact wrench and the torque bar. Then put a socket in the opening like is in the picture and start with a torque wrench to about 50 ft lbs and then work my way up to see what I actually get for a torque reading.

Does anyone know where one can get a torque wrench checked for calibration? I've had this one for years (Sears Craftsman) and it's never been dropped and always stored at "0".

Chris
 

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Way cool, you obviously know what you are doing. However something to be cautious about on forums is that there are often neophytes about, that do not understand the mechanical relationships and physics of tricks like this--they jump in to it and all of a sudden it is:

~could~
~maybe~
~sometimes~
~on a bad casting~
~at midnight Friday 13th~
~with recent evil kharma littering my wake~



gtgtbangbang said:
I cant actually remember what the bosses on the back of the pulley even look like, but there was definitely enough lip to catch the socket without skating over it and in that shear mode, no way could I machine it off unintentionally.

The crankcase fin; eyeballing it's thickness, I would trust it to hold up me and a friend and maybe the whole bike over a canyon, if loaded slowly.
A very hearty hammer blow might be able to chip it off so I would use a cheater bar, slowly loaded, if the nut is hard to take off.

Whapping a wrench handle to get the nut started off
~could~
~maybe~
~sometimes~
~on a bad casting~
~at midnight Friday 13th~
~with recent evil kharma littering my wake~

bust that fin off.

I'd done this same sort of thing lots of times to get cam & crank nuts off of valve trains, or flywheel bolts, and have yet to leave a mark let alone a broke alloy casting.

but good warning and excellent calculations.
I did make sure to use a socket diameter that lodged far back in the recess to avoid loading up the lip/vanes very edge.
 

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Daboo said:
I think what I might do tonight, is to tighten the nut like I always have done with an electric impact wrench and the torque bar. Then put a socket in the opening like is in the picture and start with a torque wrench to about 50 ft lbs and then work my way up to see what I actually get for a torque reading.

Does anyone know where one can get a torque wrench checked for calibration? I've had this one for years (Sears Craftsman) and it's never been dropped and always stored at "0".

Chris
$40 at Harbor Freight--accurate has heck...

 

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MANY MANY THANKS!

I have been rebuilding a Burgman 260 K6 engine (spanish model) and I was unable to tight the variator nut to the correct torque.

Now the bike is ready. Thank you!
 
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