Flywheel removal

Matt Read · Two Stroke Sniffer Joined: 06 May 2007 Karma :

Hi,

I am about to embark on removing the flywheel on my GS 125 (1983 kick-start) and am on a quest for any handy hints and tips. I have ordered the pulling tool from ebay, but decided on using a 16mm bolt rather than pay out for a slide hammer.

The Haynes manual gives such a vague description of how to carry out the removal it is a touch confusing. The one part of its description that is causing me particular worry is having to 'tap smartly' the bolt head (of the bolt tightened against the tool body) to jar free the rotor. Anything involving force and hammers always causes me concerns.

Additionally, before I can carry out the above I need to remove the rotor retaining nut. I have, through the use of selecting a gear and applying the rear break managed to stop the crankshaft from moving. However, as I attempt to turn the bolt I can feel a build up of a force wanting to spring my wrench back ( I stopped at this point for a think and for some advice, so I don't break anything). Is this just something I need to fight against to remove the bolt, or am I doing something wrong???

Finally, what is a Woodruff Key??? It certainly sounds interesting.

cagiva gezzer · World Chat Champion Joined: 17 Mar 2003 Karma :

https://i67.photobucket.com/albums/h294/supercitybity/Cagiva/Picture020.jpg

https://i67.photobucket.com/albums/h294/supercitybity/Cagiva/Cagiva5-1.jpg

From doing my bike. The rotor nut is done up amazingly tight, so you need to use "something" to brace it against.
____________________
"because one stroke isnt enough and four strokes waste two"

Matt Read · Two Stroke Sniffer Joined: 06 May 2007 Karma :

Hi, thanks for that. I used some additional bracing on the rotor and it held it a lot more firmly and the nut came of ok.

Now I just have to wait for the puller to arrive and I should be ok.

timjim · Trackday Trickster Joined: 31 Aug 2006 Karma :

woodruff key is a thin wedge of metal that runs laterally up the crankshaft in a groove to prevent the rotor from turning on the shaft and provides positive drive.hope this is clearer.tim Karma

finpos · World Chat Champion Joined: 13 Sep 2005 Karma :

That big nut/bolt in the middle of the flywheel has pressed the flywheel onto the tapered end of the crankshaft with a huge amount of force, a mechanical arrangement that will take some undoing.

Most of the time when you start to wind up the tension on the puller, the flywheel will pop smartly off. And sometimes it won't. If that happens, wind up the tension as much as you dare then just whack the end of the tensioning bolt and the flywheel should just sproing off. You are trying to break the tapered bond. If it doesn't, leave it under tension and go back and whack it again every 10 mins until it does.

When you go to re-assemble it, you are going to need that extra bracing because you absolutely MUST do that nut up Bastard tight (refer to manual for exact definition) again. Contrary to what it says up there, the woodruff key is only there to allow you to locate the flywheel properly (if the key is in place it's impossible to put the flywheel on wrong) and keep it there while you do up the nut. If you don't do the nut up properly and the key does start taking a load, it'll sheer, you engine will start to run like bobbins and it'll ruin the end of your crank in the process.

i.e. worry more about putting it back together Smile

finpos.