What speedo drive on a 76 with twin disc?

In the process of cleaning and freshening my caliper and MC on a stock 76, was wondering is my stock speedo drive also used on Canadian / Euro models with twin disc?
I ponder the notion of adding the second disc set up, thus considering what the complete list of parts will be.

Same speedo drive as single disc.

On the 76, it used the solid mount twin piston calipers if I remember right. To convert the right side caliper to the left you just swap the two upper caliper bolts around.
Once you get the second caliper, which might be a bit of searching. and the rotor it all bolts on.
Follow your brake line up from the caliper, you will find a junction block. It may or may not have the front brake light switch in it. Any way you remove the banjo bolt and hook the second brake line on with a double banjo bolt. A banjo bolt long enough to hold two lines.
Run the second brake line down to caliper and bleed.
I would stick with the stock master cylinder for now. It should work very well.
Leo

XSLeo said:

On the 76, it used the solid mount twin piston calipers if I remember right. To convert the right side caliper to the left you just swap the two upper caliper bolts around.
Once you get the second caliper, which might be a bit of searching. and the rotor it all bolts on.
Follow your brake line up from the caliper, you will find a junction block. It may or may not have the front brake light switch in it. Any way you remove the banjo bolt and hook the second brake line on with a double banjo bolt. A banjo bolt long enough to hold two lines.
Run the second brake line down to caliper and bleed.
I would stick with the stock master cylinder for now. It should work very well.
Leo

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Thanks Leo, yes, my brake switch is built in to the brake line junction, but my question was in relation to the speedo drive, which looks like it might be a bit crowded if a second rotor was added.

I think you will be ok. If I recall correctly the TX750 had dual discs using the 2 piston calipers you describe. Also, I think most if not all European models came with duals. Since the caliper bolts to the lower leg and not an adapter bracket, finding what you need should be straight-forward. Just follow what XSleo has said and you'll be fine. Speedo drive should be the same for all

Yes the 74-76 caliper can be swapped to to the other side by swapping the top bolts...........There were factory left side calipers for these models and they differ where the tang for the brake pad sticks out. ...........Swapping the right caliper to the left, the brake pad tang gets caught and this needs to be cut off

650Skull said:

Yes the 74-76 caliper can be swapped to to the other side by swapping the top bolts...........There were factory left side calipers for these models and they differ where the tang for the brake pad sticks out. ...........Swapping the right caliper to the left, the brake pad tang gets caught and this needs to be cut off

Click to expand...

Or file a new notch for the brake pad tang. RD guys do this all the time. Going to a dual disc setup will add considerable unsprung weight, which is never a good thing. On my RD 350, still with a single disc, I have been using this much lighter, alloy reproduction caliper for several years with good results: https://www.economycycle.com/shop/y...er-front-rd250all350all40076-78-reproduction/

Thanks Arctic! Filed that away for future use.

Norton7d said:

stock speedo drive also used on Canadian / Euro models with twin disc?

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This is all great information but, just to correct a small point, I am nearly certain that no double-disc XS650s were ever supplied to the Canadian market. I certainly have never seen one - although the modifications to build one are not complex.

Our 1975-76 bikes were the same as supplied in the US and except for some carburettor details (I think in later years) and some colours, that remained the case until the model was phased out in 1983-84.

For example, our '76 bikes were red with the very fetching brown and orange yikes stripes while the US 1976 bikes had a blue colour scheme with blue and greyish stripes (although we did get some blue ones up here too I think).

I stand to be corrected on all of that though...

Pete