Topic: Modifying speedo drive for dual disks on 550 / 750

[Tintop]

Thought I would post this early picture (edges need finishing) of my modified speedo drive for a 550.  The key is that you need a front hub with the flats machined on two sides.  I have a 550K (using), and early 750F (for next project) both with the flats.  Also have a 78 550 without.


This is what the final setup looks like.

[bwaller]

Interesting.........

Glad you could use my pics from a few years back. 

Here's how it turned out. 

[seaweb11]

I was just going to say................

I still have the print out of that photo out on my bench, somewhere


.......your just sitting there aren't you

[roach carver]

 

[Tintop]

Interesting.........

Glad you could use my pics from a few years back. 

Here's how it turned out. 

I also see that the bike was a BOTM.  Hope mine comes out that nice.

[FunJimmy]

Thanks for posting these pictures. Just in time too.
There isn't anything forcing (holding) the speedo drive against the wheel?

[754]

The original steel plate is holding it against the disc..


 Hey Jimmy, are you going to be up at OKeefe Ranch on July 10 & 11 ?

[Ricky_Racer]

Interesting.........
Glad you could use my pics from a few years back.  
Here's how it turned out.  

bwaller... Would you mind telling us what front fender you used on this build? CB650?  And how was the width with the mid-70's CB750 forks, and what did you have to do to get a secure fitting?  I'm working on a late Tracy and need a finned front fender similar to this one. Thanks in advance!  RR

[bwaller]

Sorry I haven't checked in here for a while.

That fender is from a VF500F. It's rivoted to an aluminum bracket which bolted to lugs cast into the original fork legs and acted as a fork brace.

I machined the 550 forklegs (longer, later model legs)round and made a clamp for each leg that the fender fastens to and again get the benefit of a built in fork brace. This fender is originally for a 16" wheel, but I laced up an 18" for this one, and it fits well. I did try it on a 19" front & it looked goofy....too small. 

[Ricky_Racer]

Thanks for the reply! Yeah the VT500F had a small front wheel. I think I'm going to gamble on picking up a CB650 front and hope it is the right width. Have a good one. RR

[cwchan]

Thought I would post this early picture (edges need finishing) of my modified speedo drive for a 550.  The key is that you need a front hub with the flats machined on two sides.  I have a 550K (using), and early 750F (for next project) both with the flats.  Also have a 78 550 without.


So does anyone have suggestions to modify to fit for the hubs without the flats?  i was thinking of grinding notches into the Inner diameter of the disc rotor...

[Ricky_Racer]

That'll work if you have access to a mill. Machining flats into the backside of the rotor is a second way to do the job. RR

[Tintop]

Thought I would post this early picture (edges need finishing) of my modified speedo drive for a 550.  The key is that you need a front hub with the flats machined on two sides.  I have a 550K (using), and early 750F (for next project) both with the flats.  Also have a 78 550 without.


So does anyone have suggestions to modify to fit for the hubs without the flats?  i was thinking of grinding notches into the Inner diameter of the disc rotor...

My 78 550 hub doesn't have flats.  I was thinking of taking the lip off the drive plate in a lathe, and then installing dowels in the hub which would mesh with holes in the plate.

[Tintop]

That'll work if you have access to a mill. Machining flats into the backside of the rotor is a second way to do the job. RR

Are you sure that would work RR?  My rotor (550) is a slip fit over the hub centre.  There is no clearence for the edge of the drive plate between the rotor and hub.

tintop

[fantino]

A member on the forums (Rangelov) has had a number of adapter plates machined out of aluminum for this very purpose. I'm awaiting mind, but they seem to be pretty damn slick. They're in the FS forum:

http://forums.sohc4.net/index.php?topic=76835

[Tintop]

A member on the forums (Rangelov) has had a number of adapter plates machined out of aluminum for this very purpose. I'm awaiting mind, but they seem to be pretty damn slick. They're in the FS forum:

http://forums.sohc4.net/index.php?topic=76835

I saw the post, nice piece.  But if you have the drive plate, and some basic hand tools its free.

Another way to make it is to turn the lip off in a lathe, and then bend down two edges to fit the hub flats.

[Ricky_Racer]

That'll work if you have access to a mill. Machining flats into the backside of the rotor is a second way to do the job. RR

Are you sure that would work RR?  My rotor (550) is a slip fit over the hub centre.  There is no clearence for the edge of the drive plate between the rotor and hub.

tintop

Sorry I missed your posting, TT. I don't know about the CB550, but I've seen reliefs cut into the rear of the CB750 rotors. Of course the chrome trim ring is unnecessary then. I'm using old sandcast drive plates that work like the cut 'n bent ones, so I haven't had to do either yet.  RR

[Tintop]

That'll work if you have access to a mill. Machining flats into the backside of the rotor is a second way to do the job. RR

Are you sure that would work RR?  My rotor (550) is a slip fit over the hub centre.  There is no clearence for the edge of the drive plate between the rotor and hub.

tintop

Sorry I missed your posting, TT. I don't know about the CB550, but I've seen reliefs cut into the rear of the CB750 rotors. Of course the chrome trim ring is unnecessary then. I'm using old sandcast drive plates that work like the cut 'n bent ones, so I haven't had to do either yet.  RR

Those are the ones that Honda sold individually later, for dual disk upgades.  Tried to find one for my project, but ended up having to make one.

[nippon]

We made some of the modyfied speedo drives for double disc setups.

nippon

[Tintop]

We made some of the modyfied speedo drives for double disc setups.

nippon

nice looking piece nippon.  That's along the idea of what I had planned on doing if I had one machined.  Only difference being I had thought of using dowels instead of screws.  The speedo drive holds it in place once assembled on the axle.

tintop