Topic: Looks like I need one last piece for my dual disc conversion

[XN]

From this picture I'm assuming I need item 15 for the "CB500/550 speedo drive plate" is that correct?

[bwaller]

Yes.

[bryanj]

OH GOD NOT AGAIN!!!!!!!

The 500 speedo drive is IDENTICAL to the 750 one

[KingCustomCycles.com]

Or a front axle spacer if the speedo is not wanted or needed.

[bwaller]

Well XN, I have to admit you had me back in my seat last night trying to fiqure why you would have to ask why a 500 wouldn't need a speedo drive.

I just wasn't insightful enough to think you'd be asking about a 500 drive for a 750. You no-doubt read Bryans response! There had been a notion around that a 750 needed a 500 drive to make a speedo work. Bunk!

Sorry Bryan for my part in spiking your blood pressure. 

[bryanj]

No problem mate, at least we haven't been asked for paint codes recently WHERES THAT WOOD!!!

[XN]

Well XN, I have to admit you had me back in my seat last night trying to fiqure why you would have to ask why a 500 wouldn't need a speedo drive.

I just wasn't insightful enough to think you'd be asking about a 500 drive for a 750. You no-doubt read Bryans response! There had been a notion around that a 750 needed a 500 drive to make a speedo work. Bunk!

Sorry Bryan for my part in spiking your blood pressure. 

So what I got will work? No speedo parts needed?

[void909]

Check out my post called dual brake conversion. I think thats what its called

[ev0lve]

There had been a notion around that a 750 needed a 500 drive to make a speedo work. Bunk!

I got a 550 speedo drive based on these instructions and noticed it was the same as the one currently on my 750.
http://www.salocal.com/sohc/tech/dual_disks/dual_disks.htm

Need,

1x caliper arm
1x caliper
1x disc
6x8mmx110mm bolt (for disc)
1xlower brake line (that makes two all up)
1x steel brake line to caliper (which again makes two all up)
1xdouble banjo fitting (for the two lower brake lines)
1x bigger master cylinder (some say GL goldwing mastercylinder are ok.. I used one off a modern dual disc bike)
1xcb500/550 speedo drive plate (no modification)
2x6mmx30mm bolts and washers
1x8mmx35mm bolt and washer

Other than that though the tut looks complete. Anyone with duals up for taking a look and verifying it's good info? He doesn't seem to mention any mods to the drive plate and neither does anyone in this thread but I've seen folks talking about it.

Thanks!

[crazypj]

From this picture I'm assuming I need item 15 for the "CB500/550 speedo drive plate" is that correct?

NO
 you want part 9, modified as explained all over several dual disc conversion threads
 
PJ

[ev0lve]

NO
 you want part 9
 
PJ

Thread hi-jack in progress. Alert the proper authorities as I insert my questions 

Is part 9 different for a 500/550 than a 750?

[crazypj]

you need slapping up't side of head.
 Later model 550 and 750 use same hub (1976+)
Not certain of earlier ones but rotors etc fit late model so bolt spacing is same (I've done it so know they do)
PJ

[ev0lve]

I'm not the OP but probably need the head slapping anyway. So, risking more slappage, it's the drive plate that's at issue on a stock 750. Gonna have to do some studying I think.

[bryanj]

The different one is the VERY early 750 after that all the 500/550/750 ones are the same but can be MODIFIED to fit see the pics in the other twin disc post running at the moment

[bryanj]

Edit:= post with pics is

http://forums.sohc4.net/index.php?topic=41218.0

[ev0lve]

Now that post is the #$%^! Many thanks!

[mystic_1]

Wow, and there you have it!

Great post and pic Fishhead!

mystic_1

[MCRider]

Wow, and there you have it!

Great post and pic Fishhead!

mystic_1

I PMd the author Ben Hiles of the Dual Disc Conversion piece http://www.sohc4.net/index.php?title=Dual_disc_conversion which so many people have referenced. It was very well done and i don't want to take anything away from the effort. However he concurred that he erred on the reference to the CB500 Speedo Drive Plate. He had gotten one for a sandcast CB750 (lucky him) and thought it was from a 500/550. It is no longer available anywhere.

So the references others have made, (Bryanj, page 1 of this thread) myself as well to modifying the stocker by grinding and bending tabs (the neanderthal way) or having one machined down and dogs welded on (more elegant) is the proper thing.

I am attempting to find a moderator to help us edit that piece to delete the reference to the 500/550 piece and include modification insrtuctions.

[mystic_1]

Hey Ron, post the pic of the drive plate you had made up, that thing was nice.

mystic_1

[MCRider]

Hey Ron, post the pic of the drive plate you had made up, that thing was nice.

mystic_1

Thanks, I'm ahead of you except i can't find it! Not in my photobucket file. Must be in My Pictures in my PC. I'm still looking.

Found it: The one on the left was made by a machine shop for about $20. It is a slip fit into the disk and he put a bushing into it so it fit to the axle. Completely unnecessary, he was just showing off. Two nice tabs welded on for the drive purpose. The one on the right i made with a grinder and vice grips. It was in Phaedrus I for 50,000 miles. The other is for Phaedrus II.

[MCRider]

Hey Ron, post the pic of the drive plate you had made up, that thing was nice.

mystic_1

Thanks, I'm ahead of you except i can't find it! Not in my photobucket file. Must be in My Pictures in my PC. I'm still looking.

Found it: The one on the left was made by a machine shop for about $20. It is a slip fit into the disk and he put a bushing into it so it fit to the axle. Completely unnecessary, he was just showing off. Two nice tabs welded on for the drive purpose. The one on the right i made with a grinder and vice grips. It was in Phaedrus I for 50,000 miles. The other is for Phaedrus II.

[crazypj]

You need cut thread bolts not rolled thread bolts. Rolling the thread onto blank makes it larger diameter than original material (cheaper to produce but thread isn't quite as strong))
If I cant get what I need from manufacturer I tend to make new or modify whats available.
 Been using quite a lot of high tensile stainless bolts recently
PJ

[ev0lve]

Cross posting this from my project thread but if anyone will know it's probably you guys   

I've modified my speedo drive plate using a Dremel (love that thing) and there's a bit of slop when fitted to the hub; maybe an 1/8 inch side to side. Is that how it's supposed to be or do I need to trim the diameter of the plate and bend the tangs down instead of just trimming the bell and leaving the bits that form the tangs? Pic attached and thanks!

[bwaller]

It's best to have a little play once the speedo drive & axle are in place and tight. As long as the drive plate is well located your good.

But it also would be wise to clean up your work so no-one gets a metal splinter. 

[ev0lve]

Good news then! I was planning on grinding it down a little. Just stopped when it was a little loose to make sure I'd understood everything correctly. Now I just have to drill the discs and it's on!

Thanks!