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Swapping the entire groupset

It was finally time to try and swap all the parts for my groupset on my racer, a GT GTR Series 5. I like the bike and frame, but I was not happy with the drive train. I like (apparently, didn’t know that myself when I started with the road bike) to tackle uphills. But the ratio on the bike was on the heavier side, with 39/53T and 11-28T. I do not mind going slow up the slopes, but I would like to do them in one go without pauses 😛

So I bought a complete groupset to swap out all parts. I did this instead of buying the separate parts since this meant that all the components would fit together.
I’ve never really wrenched a bike before, so I had planned to send it all to the local bike shop, but figured I could try and see how much I could get done myself.
New groupset is a Shimano 105 5800, 34/50T  and 11-32T.

So first thing was to buy the tools I needed. The old crank and new needed different tools, so I had to figure out what kind of crankarms and bottom bracket I had. Turned out it was a square bolt, sealed bottom bracket. So I needed a crank puller to get the crank arms off. I turned to Biltema, a chain of cheap tools and everything. Also needed a tool to remove the bottom bracket and the rear cassette. This is what I bought:

So I got all tools for cheap, except the Hollowtech II-tools, since I had to buy a BBB-branded one as Biltema didn’t have a tool for this. But right tools are important, so so be it 🙂

First I assembled the rear cassette and tightened it on my other wheel set.

Rear cassette tool from Biltema

It says to be tightened with 40Nm so I used a torque wrench.

Tightening to 40Nm

So the tool worked splendid. No need to spend several hundred kroner on a branded one.

Next up was to remove the crank arms. I removed the pedals first, since I’ll be reusing them.
Used a 8mm allen wrench to remove the end caps. They don’t hold the crank arm on, but out they must go.

Remove the both bolts..

Square tapered bottom bracket indeed. So now it’s time to get the crank arms off, what it does is it screws into the arm part, and then you push it off the square part with a lot of force (at least for me..)

Arm part screwed in:

This needs to be fairly tight on.

And then the silver part screws in and it will then push the crank arms off.

This turns clockwise to pull the arm off.

I have seen videos of this on YouTube, and all of them removes the arms quite easily, with about the same amount of leverage as this red handle gives me. That was not the case for me. I gave it all I had, but it didn’t budge. So I found a pipe (hoover pipe was all I found, but it did the trick)

More leverage!

Then the arm/chain ring came off, finally. I was afraid I was doing something wrong, but it was just stuck on really well.

One problem with more leverage, is just that. Too much force. This happened when I tried to remove the other arm…

…this is after I bent it back as good as I was able to

This was no good, but the crank arm puller tool took a normal 15 wrench, so I used that with the hoover pipe for leverage. At least that one didn’t bend, and I was able to remove the arms successfully.

Now I could finally get to the bottom bracket itself. It’s a sealed type, and here it is important to start from the non-drive side.

Insert and remove, I think it was counter-clockwise here.

This will remove the end cap, which is on the non-drive side. When removed, the actual bottom bracket can be remove from the drive-side. And this is what it looks like.

it’s out!

Now clean out the crank area..

This can get dirty. Be sure to get everything out

New bottom bracket! Ultegra one actually..

This needs another tool…

A plastic adapter/tool is supplied with the bottom bracket..

Looks a bit different, and much lighter..

The bottom bracket is insert from the drive side and fastened with the tool with the big mouth. First the adapter on, though. And then the tool around the adapter.

Look for the sign on the adapter or the bracket itself for what direction to tighten.

Finish off with the non-drive side. Looking good!

Time to insert the chain wheel and attach the arm!


So the big chainweel has a protrusion on the backside I forgot to photograph. It inserts first from the drive side. Be sure to get it all the way in, you might need to hit it with a rubber mallet.

Then slide the arm on. It should only be possible to insert it the right orientation.. and also insert the end cap.

End cap… Insert this before fastening the arm

And use the tool supplied with the Hollowtech II bottom bracket tool.

Finger-tighten it, not too hard

To secure the arm to the crank, there’s to allen keys on the arm. They must be tightened alternately. A little on one side, then a little on the other. Not all the way in on one side first.

a little on each side, alternating..

I then attached the pedals again. All is looking good!

Now I removed the front derailleur, which is a clamp-on type. The new one is the same. First I took the wire off, then removed the fixing screw.

Doesn’t look like much, but it has an important job…

Front derailleur, Shimano FD-5800-F.

Jumping straight to the rear derailleur…

Anyway, time to remove the old chain. Used a chain cutter..

Biltema Chain cutter. Got the job done.
Quite dirty job, though..

Removed the old derailleur and got the new one on.

Reused the black part that attaches to the frame

Now was a splendid time to clean up the frame, with nothing in the way for a good scrubbing.

A white bike requires some cleaning…

Used some car products I have, Surfex HD did the trick

A job well done.

This was all the drive train components, the last part now are the Shimano brifters, the integrated brake and shifting levers. Start with removing all the old wires and then the handle bar tape.

My old 8-speed Microshift levers are removed by loosening this 8mm allen screw.

It’s in there! Then slide the lever off the handle bar

I also ran new cable housings for both gear wires and brake wires. My rear brake cable is an internal one, so I had to figure out a clever way to get a hold of the housing on the rear here. Turned out a small allen key was the best tool to grab a hold on it and get it out of the frame.

Hah! Success!
Beginning to look like a bike again

oh yes, the brifters. They slide back on, and need to be adjusted. I learned that one way to get them pretty well adjusted, was to have it loose, and then press something flat against the bottom of the handle bar, and then adjust the brifter up or down so that the brake lever was level with the bottom of the handle bar, like this:

Now the brifter can be tightened.

Test handling the bike this seemed like a good place for the levers.

Last part was to attach the chain. Also it has to be in the correct length. I cut it too long, so I need a new link so I can cut it a bit shorter.  But almost done! All parts are assembled on the bike at least, so soon I will be able to take it for a ride.


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