Custom 3 Jaw Puller

I was working on my 1988 CBR600FJ and wanted to remove the flywheel to gain more access to the clutch. Unfortunately a special threaded tool is needed to remove the flywheel as it is pressed onto the crankshaft. With some care the flywheel can also be removed by using a puller. Non of the pullers I had on hand (nor any that could be purchased locally) fit the bill so I decided to fabricate my own custom one. Since pullers are used to exert hundreds (sometimes thousands) of pounds of force it is crucial that they are strong and well built. Just a few 10's of pounds off center could break or damage parts being removed. Being myself I already had it in the back of my mind that my puller would run circles around the best puller that could be bought.

It all began with a plan. I sketched out the basic idea for what I wanted and then went to Home Depot to acquire the necessary parts. I have a pretty good idea of what most hardware stores stock so I my design resembled the parts I expected to find.

I started by cutting out the three arm pieces out of hollow 1/8" thick steel square stock. There are two types of tools in this world: really good tools that help you work and poor quality tools that can do more damage than good. The difference between the two are how well they are built. How well are they dimensioned, what type of material they are made of, and the machined accuracy of the pieces that make the tool determine how well a tool is built. Most people are of the mindset that a cheap tool is useful when you just want to do a job once or twice and that high quality tools (often expensive) are only needed if you work as a mechanic. This is not true! If you need the job done right, don't be cheap when buying your tools.

Checking the fitment to look for problems before I start.

Drilled three holes and cut three spacers to fit inside them. The bolts will ride in the spacers to provide smoother operation.

To give you an example of what I meant. I also chose bolts that were not threaded for the portion that would ride in the spacer.

There was not much access to weld to but I still managed enough for a strong bond. The weld is more to support the spacer. It is not meant to support a load.

This is where the fun begins! I align the center threaded piece in the vise with a level.

Once the middle piece was aligned I checked the alignment of each arm.

In the previous picture you saw me use a C-clamp to hold just a single arm to the center piece. I later realized having one arm welded would make it more difficult to clamp the next arm. Thus I held all the arms to the center piece with a few rubber bands. The one arm has the hole vertical which was mistake I corrected before welding. Also I re-checked the alignment of each arm with the level.

With all the pieces welded I tested that the threads were still good on the center piece by threaded the push rod through it. No trouble here.

Next I cut the legs for each arm.

I also cut the connecting pieces for each leg.

In order to stay accurate I drilled the pilot hole through all of them at the same time. Thus I could use the pilot hole in each one when drilling the full sized hole and not worry about getting the holes in the same area.

Checking the alignment of the connecting pieces to the legs before I welded them.

Got one leg finished!

I also used the bolt as a guide when aligning and clamping the attaching pieces to be welded to the legs.

I double checked the distance from each bolt to the top of the leg for each arm. As long as the distance was not off more that ~.010" the tolerance of each leg would be 'close enough'. This was my rule of thumb and I bested it by the time I was finished. If the bolts were not all really close to being the same distance apart, I would have had legs that were slightly longer than the others.

Got all the legs finished!

Test fitting all the pieces I had completed thus far.

The legs are finally completed with the feet attached.

The center rod was made out of 3/4-13 steel threaded rod.

I started by trying to cut a hex head into the rod to fit a socket over but this proved too tedious so I just welded a bolt to the top.

The completed puller.

It turned out that my 3 jaw puller did not fit as the legs were spaced out just so that no matter how it was orientated, one leg would run into the clutch. This is what using a store bought 2 jaw puller looked like.

So I built a 2 Jaw puller!

And used it to pop the flywheel off.

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