Topic: Honda CB550F - 1977

[DVL123]

Hi all,

Let me first shortly introduce myself. I am an (almost) 30-year old guy from Belgium. I have always been interested in cars, esthetically and mechanically, but never did anything with it because I do not have any skills in this area. In more recent years, my interest shifted from cars to motorcycles. Especially old motorcycles. After some considerations, I took an impulsive decision, and bought my first motorcycle. I bought a Honda CB550F from 1977, in very good and running condition. My plan is to convert this motor into a cafe racer. (see first picture)

As mentioned before, I do not have most of the skills to do this all by myself at this moment. I am not able to weld, paint, revise the engine, etc. I know the basics of car/bike mechanics. What I do have is some spare time. I would like to take some time to learn new skills, read on certain subjects, redo stuff if not up to standards. At this point, I have already taken down the bike, taking a lot of pictures in the process. I have taken out the cabling, and have the wiring more or less figured out. I have ordered some new parts, sold some old parts and the 'plan' for the bike is more or less clear. The first step in rebuilding is taking off some unnecessary metal from the frame, and installing the seat hoop. (see second picture for current state)

I already have a ton of questions on many different parts of the bike (new wiring, painting of the frame, batterij box placement). I will keep these questions for a later moment, and try to post them in an ordered way

Ciao!

[Stev-o]

Ciao from Texas!    I also have a blue 550F...

[Bankerdanny]

Welcome.

Here's my blue 550F I moved on to a new owner a couple years back.

[jakec]

Cafe would be a mistake on a nice bike like that.

[DVL123]

Update 1!

Started working on removing unnecessary bits and pieces from the frame. Getting these pieces off is not that difficult, making sure that all metal work is smooth again is the tricky part. For now, I am happy with the result. I will have to do some small places once more to get them up to standards.

Afterwards, I started working on the installation of the seat hoop. I did the measurements and cut down the back. I inserted inner tubes, to make sure the hoop can be welded onto the frame itself. One problem... I ordered the wrong size seat hoop. I checked the available sizes at the suppliers' website, but the size I needed was not available. As a solution, I cut the hoop in half right in the middle. Afterwards, I will weld a piece of the tube back in. Next steps will be to finish with the last pieces of metal I still have to cut and to cut the seat hoop at the correct length. The goal is to end the seat hoop right at the middle of the rear wheel.

At the same time, I am buying all parts I will need to put the bike back together. I would like to replace the different gauges. For me, these take up too much place. I would like to replace this by one simple small gauge with all functions included. However, the only function that is not included in this new gauge is the tachometer. Could I just remove the cable from the engine towards the tachometer without running into issues with the engine? Or is it vital that I leave this cable on? 

Updates following soon!

Ciao!

[flatlander]

groetjes from north of the border!

i sort of agree with jakec. these bikes were relatively minimal from the factory, i.e. already pretty "cafe". there is not an awful lot that you can just pull off to improve things. and most people that turn them into cafe-racers don't actually succeed in making them better. best is to start with a very clear plan. but it's your bike, and your choices.

you can remove the tach cable - but then also remove the housing and the tach cable drive that's within it, from the top of the engine. there are plugs available. buy one of those to close the remaining hole so that oil does not come out and crap does not go in.
do you have an alternative? a true cafe is about performance and speed, not only looks. having a tach is essential for performance oriented riding (or any riding, in my mind).

i also have a blue F 



the link in my signature is a thread documenting all the work i did. you may find some useful stuff in there.

[DVL123]

Let me elaborate a bit more on the plan I have for this bike. My goal is to own a bike that is 100% up to my personal taste. So, I do agree that the original bike already has a very clean look, I was even hesitant to start working on the bike. I am calling this a café racer project, because the look corresponds mostly with how I would like the bike to look. I am in no way trying to get a better performance of the engine. First because I do not have the knowledge/skills at this moment to do this. But also because I am not trying to convert this bike into a racing bike. I just want a nice-looking bike to take out on a quiet sunny day.

The work I am planning to do is rather limited. Take off some parts, repaint the frame and tank, add clip-ons, new gauges, change the rear end + seat and update the wiring.

Thanks for your comments on the tach-cable. I already had the feeling it would not be a great idea to just remove the cable and leave a hole in the engine 😊. Your point on riding without a tacho is also valid, I might have to do some research on a meter that has all functions included (speed, tach, oil, lights, neutral etc).

Ciao!

[SuperSport Charlie]

And yet another SuperSport 1975!


Sent from my iPhone using Tapatalk

[calj737]

Afterwards, I started working on the installation of the seat hoop. I did the measurements and cut down the back. I inserted inner tubes, to make sure the hoop can be welded onto the frame itself. One problem... I ordered the wrong size seat hoop. I checked the available sizes at the suppliers' website, but the size I needed was not available. As a solution, I cut the hoop in half right in the middle. Afterwards, I will weld a piece of the tube back in. Next steps will be to finish with the last pieces of metal I still have to cut and to cut the seat hoop at the correct length. The goal is to end the seat hoop right at the middle of the rear wheel.

Before you go too much farther with that hoop, you had best ascertain the space required between the hoop and the tire with your new design. A flat hoop terminating over the tire will contact the tire under suspension compression. Even dropping to a 17" tire is very likely going to hit. So you probably need a 17" rear and 1" longer shocks, which then throws off the front steering geometry. Clip-ons on these bikes (with stock forks) really necessitate rear sets. Else you're lunged forward with your ankles ahead of you. Not good posture.

The domino effect of style changes... I'm all for chopping these bikes up and making them "your own" but best you fully develop your plan from the onset to avoid unforeseen challenges later. Especially if your skill set and toolbox is limited. Otherwise, this bike will get very expensive quickly.

[DVL123]

Update 2!

Had some time to work on the bike again in the past days. First on my list was the installation of the seat hoop. I already cut down the frame, now I did some measurements on where the seat should end. I cut down the seat hoop to match the measurements. For now, I have attached the seat hoop using some inner tubes. Later, this will get welded onto the frame itself.

The next step was to create a cardboard example of how my seat pan should look. I think I got the basic form right. I also produced some support for the seat pan, which will be welded to the frame as well. I am still trying to figure out which type of material to use on the seat pan. I am in doubt between a steel plate with a thickness of 1mm, or an aluminum plate with a thickness of 2mm. I am also planning on making some support brackets for the seat hoop from the same material. Any suggestions are welcome!

Today, I started by stripping the last parts from the frame. Afterwards, I used a power washer to get most of the dirt and oil off, it seems like the bike was never cleaned before. I managed to get it almost clean for now. Will have to do a detailed cleaning afterwards, to get off the last pieces of dirt and oil.

Ever since I took the wiring harness out, I have had many questions on upgrading the wiring and installing it back afterwards. I created a new thread for my questions (Wiring 101). Feel free to comment on this thread as well, all information is much appreciated!

Ciao!

[DVL123]

Before you go too much farther with that hoop, you had best ascertain the space required between the hoop and the tire with your new design. A flat hoop terminating over the tire will contact the tire under suspension compression. Even dropping to a 17" tire is very likely going to hit. So you probably need a 17" rear and 1" longer shocks, which then throws off the front steering geometry. Clip-ons on these bikes (with stock forks) really necessitate rear sets. Else you're lunged forward with your ankles ahead of you. Not good posture.

The domino effect of style changes... I'm all for chopping these bikes up and making them "your own" but best you fully develop your plan from the onset to avoid unforeseen challenges later. Especially if your skill set and toolbox is limited. Otherwise, this bike will get very expensive quickly.

Much appreciated info! My plan was to get most of the parts fabricated, before I weld anything on the bike, just to prevent accidents like this  . I might need to reconsider using a straight hoop, an upswept hoop can give me some more space. I will try to have the same spacing between the rear wheel and the hoop as I had when using the stock rear fender

EDIT:  I am chopping off the passager part of the seat,  I will never have  extra weight at the back of the bike. Am I right in thinking this takes off a small bit of the clearance I need between rear wheel and hoop?

[calj737]

You won’t have much luck welding aluminum to steel if you opt for an aluminum pan. 18ga steel sheet is plenty capable.

[ralt12]

For a smaller, lighter instrument set I opted for this: https://cognitomoto.com/collections/gauges/products/cognito-moto-gps-speedo-and-small-tach?variant=1332926657

Big tach, small speedo, or big speedo/small tach.