Nice...not as heavy as I had thought.Here is a 5mm thick cast Yamaha disc
Yes, I really do appreciate the look of a traditional paralell twin, be it XS, Bonnie, Rocket, Commando or Interceptor. Hell, even a Guzzi looks right. While most other V-twins look slightly more awkward somehow. But the relative lack of vibration and more revvy nature of a Duc is quite enjoyable tooTo me a large part of the XS sex appeal is the symmetry of the jugs
Ya, a Ducati may have much better stats..
I’d say carry on with Symmetry Pete!
We know Pete appreciates a good set of symmetry
Not sure on the thickness, but fairly thin. They weigh about 3 1/2 lbs...vs. the 7 lbs stock rotor.
I have a 5mm thick SR500 disc on my '78. It's about 1.5 pounds lighter than the original 7mm thick 650 disc. Honestly, I can't say I notice much difference in handling. My spare wheel has an original 7mm disc on it and I've swapped it in several times, so I got a back to back comparison. Like I said, no difference that I could tell.
Whether you feel it, or not, it turns faster if lighter. Where you will feel it is bumps. More unsprung weight will hit you in the hands/butt.
Exactly. And reduction of SPRUNG weight will just make it even worse. So removing starter, lighter battery (or a cap.), PMA, aftermarket pipes, seat, or even dieting will hurt suspension and ride quality if one is not reducing unsprung weight at the same time. I can definitely feel that my front end has improved immensely, after losing more than 10 lbs unsprung weight, and fitting new springs and adding emulators (unfortunately not RT....) As everything was changed at the same time, it is hard to tell what improved suspension the most.Whether you feel it, or not, it turns faster if lighter. Where you will feel it is bumps. More unsprung weight will hit you in the hands/butt.
View attachment 147039 Keep it fun Pete !
Some folks are just going to explain their ideas of the physical workings of Your motorcycle
MaxPete, Career mechanical engineer, Life long XS650 rider. You Got This !
I did in no way intend to state the obvious to those who already got it, like MaxPete and many others. But I am sure not all forum members are mechanical engineers, physicists, aircraft techs etc. So I may have gone in too much detail on this sprung/ rotating weight thing, even if it has pretty significant impact on how these bikes work.
It’s no problem with detail ArcticXS - everyone benefits from learning and among the whole community there is an amazingly wide spectrum of knowledge and experience.
Besides, I'm an engineer and we are sometimes known (unfairly in my opinion) for providing lengthy and detailed technical explanations which hardly anyone understands, but which are absolutely necessary for completeness and to ensure that nobody makes a big stupid mistake with vital technology - that only we engineers can truly comprehend, and are capable of dominating.
I simply cannot imagine how we engineers got the reputation of being "wordy".....
In terms of the bikes and the best brake set-up, I think it’s all about how and where one rides and what one likes. In our area (Lakeview's and mine) there are virtually no hills of any size (and I mean NONE at all) and few twisty roads, so suspension issues like unsprung mass fade a bit in favour of braking effectiveness.
There are two reasons for this:
Cheers,
- we have lots of nitwit 20-something dipsh!ts racing around in highly polished black BMW 3-Series cars with furry dice hanging on the rearview mirrors and...
- ...much as it pains me to admit, yeah, I love the look of the bike with double disks.
Pete
G'day Pete from the bottom of the planet,
Mate I am thinking of putting a second disc on "Puff the tragic wagon".
I have noticed that in the parts cattle dog it is a factory option.
Hopefully will stop better