Notes on pulling '06-'08 Flywheels

I noticed something while pulling the flywheel on my '06 to swap it with a GYT-R unit that could cause considerable frustration or possible damage for someone if it were to go unnoticed.

The puller used for this job is the same as for a CRF450. The puller has internal threads, and a pressure screw to bear against the crank, as you might expect. Less usual, but a nice detail, is the thread protecting cap that screws onto the crank, and comes with at least the Motion Pro puller. The idea is that the cap screws on the crank to provide a hardened surface for the pressure screw to bear on other than the end of your $300 crankshaft. So, it's a good thing, right?

Well, yes, except that, at least in the case of the MP tool, the protective cap can be screwed on so far that it contacts the flywheel, just like the retaining nut does, and would serve the same purpose, which of course would work against any attempt to remove the flywheel. There are no instructions that warn anyone against this, you just have to see it and realize the potential problem.

So, the thing to do is to screw the cap onto the crank only part way as far as it will go, leaving about a quarter inch (6 mm) gap between the nut and flywheel as shown here. That will give the flywheel enough room to pop free without interference. Then it will slide off once the puller is removed. Note also that the cap may turn down a little tighter than where you left it as the puller works, so give it just a bit more than what you see here.

One of the cool things about these flywheels is that they require no special holder because of the 19mm wrench flats cut into them.

flywheel.jpg?t=1241968474

Have you rode it yet?

Good info. This should be added to the common thread sticky. :worthy:

Nope. This weekend. I'll let you know what I think after that. (of course, if I don't like it, it'll be your fault :worthy: ).

Nope. This weekend. I'll let you know what I think after that. (of course, if I don't like it, it'll be your fault :worthy: ).

What size <weight> flywheel are you trying?

The Off-Road GYT-R flywheel (GYT-2S297-50-50) "Adds 9.21 oz. for an inertia mass of 6.15 kg-cm² (stock inertia mass=3.8 kg-cm²)"

Had the 8oz Dr.D in my '03 and loved it. With all the hard pack around here, I think I might like this one, too. The stock flywheel weighs next to nothing.

Good idea gray! I thought about posting something like this when I did my flywheel on my 06 but never got around to it. Could save someone a lot of trouble!

Nope. This weekend. I'll let you know what I think after that. (of course, if I don't like it, it'll be your fault :worthy: ).

so????

so????
You would think that after so many years of working in the trade, I would know better, but when I pulled the new one out of the box, the weight looked a little bit small. On closer examination, I discovered that I had been sent the wrong flywheel ( the lighter GYT-2S297-50-00). So, I put the stocker back on. I'll post once the real one's in place.

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