The CB1100 Community Forum

Using the original tank or a custom one?

Original tank so far. It was dented and I am filling in the Honda badge relief and removing the badges. I don't like the filler cap so I may end up with a different tank at some point.
So, I weighed the Honda and Ducati rear ends. It was a little surprising - maybe. All in pounds....

Honda:
Swing arm - 21.4
Wheel, tire, sprocket - 39.8
Shocks and axle - 9.4

Honda Total - 70.6 pounds

Ducati:
Swing arm - 27.6
Tire and shocks - 22.8
Wheel - 8

Ducati total - 58.4 pounds

The Ducati swing arm is heavier but the Honda wheel, tire and shock group is made of lead. So the rear is already 12.2 pounds lighter, all from unsprung weight.

You had me at "Café Project". I'm all in! Keep it coming....

What Honda wheel are you comparing it to?

jtopsio, he's talking about the OEM Honda wheel for the CB1100, isn't he?

(10-03-2018, 05:53 PM)Cormanus_imp Wrote: [ -> ]jtopsio, he's talking about the OEM Honda wheel for the CB1100, isn't he?

wire spoked, cast...

Cast.

(10-03-2018, 10:31 PM)Cormanus_imp Wrote: [ -> ]Cast.

It amazes me how two wheels (with tyre) of similar size and techonolgy (cast aluminium, I assume) show such a difference in weight.

Well, the #'s he listed are not the same.

One he has the tire with the wheel, the other without. No mention of Ducati sprocket. Etc.

In theory, if the bike is still apart, he could separate and give more comparable numbers.

He also mentions 12.2 unsprung- but that isn't true- there is a midway point in the suspension that transitions from sprung to unsprung, both on the shocks and swing arm/linkages. Are you going to feel it? Nah... but just a clarification to a mentioned technicality.

The rear sprocket on the Cb is steel. Quick and easy to drop weight by going to aluminum. Not drastic, but easy.

Biggest comp would be direct weight of wheel/tire/sprocket as an assembly- that is what is being moved up and down..

The numbers are actually the same. If you add them all up, the total equals the same set of parts for each bike i.e. wheel, tire, sprocket, brake disc, shocks and linkage, axle/hub and swing arm.

Check the picture. The Ducati sprocket/disc is part of the swing arm hub and on the Honda it's attached to the wheel assembly. That's why the Ducati swing arm is heavy and the Honda wheel is heavy. But add everything up and it's the same set of parts. Ducati is way lighter.

Different bikes with different design parameters.

I agree about the unsprung weight comment, but that would be too hard to work out exactly. It's close enough - for me.