Wednesday 6 December 2017

The new TR1 motor - Getting the rotor off (part 12)

Now this is one of the jobs dreaded by most, when in fact it's not that bad, in case you're using the correct tools for the job. The most important one being a hub puller.

The three bolts are m8x80 bolts (but the length depends on the puller used). It is of utmost importance, that you leave the nut on the end of the crank and only loosen it by three or four turns.  Otherwise you risk mushrooming the end of the crank or shattering it completely.


On the back of the rotor is the primary drive sprocked for the rear cylinder and the sprocket of the oilpump, which will remain on the crank after you pulled the rotor off.


Normally you don't have to heat the center of the rotor, but if someone overtightened it in the past or used some loctite or the wrong woodruff key... (The list goes on, you wouldn't believe the things I've seen in the past!) Then you can help yourself with either a proper oxy-acetylene torch or a silver soldering torch and heat up the taper on the opposite side of where the slot is. (That's the spot where it exercises the strongest clamping force on the taper.) Use the smallest possible nozzle you can and as hot as it will go. Tighten the puller and be prepared that it will literally "jump" off the crank that way.


There's six springs with six pins on the back. Dare to guess, why I am telling you this? 😉


And that's the left side without a rotor installed, as you will see, it really is possible to remove the oilpump with the rotor in place. When re-assembling I'll also show you, why I put the primary drive sprocket onto the rotor and then install and not the way round the Yamaha manual tells you to. 


All looking pretty tidy in there. So it's well about time to get those cylinders off and then take the cases apart. I can almost smell performance now. (Nope, that's just the scent of hot oil in the workshop from heating up the bearing!)


No comments:

Post a Comment