| Author | Message | ||
     Fresnobuell |
I did a search since I figure this was a question that must have been a topic at one time, but I didn't find an obvious answer. If there is a thread somewhere, please point me to it and we dont' have to elaborate here. What is unsprung weight? How does it help the performance of a bike? It seems to be such a big deal. thanks for helping me understand. Harlan | ||
| Jlnance |
Harlan, Unsprung weight refers to the weight of everything below the shocks. It's important because that is the amount of weight that has to move when you roll over a bump or pothole. The less unsprung weigh there is, the faster the tires can move and the better the bike will stick to rough pavement. | ||
| Blake |
Unspring mass also includes the lower fork/shock tubes, damper/cartridge assembly and a portion of the spring(s) themselves. Anything that moves with the wheel. Part of the mass of the swingarm is unsprung. | ||
| Johnnylunchbox |
It's all about inertia!!!!! | ||
| Lovematt |
The idea is to reduce as much weight that moves when a spring compresses...this will reduce the forces that the spring has to overcome each time the wheel goes over a bump. A good way to think of this is a slingshot or crossbow...if you were to throw a heavy rock at the slingshot it would take a while to absorb the force and spit it back out again. If you threw a light rock at that same slingshot then it would take less time to absorb it and spit it back out. The back wheel is the same way...if there were a lot of weight that was unsprung when a bump was hit the wheel would go up and over the bump but when it passed the bump...it may stay up in the air for a bit of time as the spring works to push it back down. With less unsprung weight the wheel follows the road better, there is less hopping around, and the bike generally stays stuck to the road a lot better. | ||
| Fresnobuell |
thanks to each person who answered my question. Great info and it is much clearer now. Would the rest of the bike (what doesn't move with the wheel) be considered "sprung" weight? Just trying to figure out how they came up this the term- "unsprung". | ||
| Lovematt |
Basically you are right...what is "held up" by the spring is sprung and what is "pushed down" by the spring is unsprung. Below are some URLs that may give some more info...the site might be a bit more automotive based but this page is pretty good.it is a bit automotive based but shows what the components are doing...there is some good links leading to other things at he top of the page... http://www.chris-longhurst.com/carbibles/suspension_bible_bikes.html http://www.chris-longhurst.com/carbibles/suspension_bible.html | ||
| Panic |
Read my article: http://victorylibrary.com/brit/M-sprung.htm | ||
| Lovematt |
Hey Panic...that is good info! | ||
| Doughnut |
How much of a Buells weight is un-sprung? How much on your "average" motorcycle? | ||
| Fresnobuell |
Wow, thanks Panic. Now it is REALLY clear. great info. | ||
| Blake |
"Mass", not "weight". Call me picky.  | ||
| Indy_bueller |
Ok, I call you Picky.  | ||
| Bomber |
doughnut -- different for differ models -- varies by tire selction, as well -- I would guess that most buells compare pretty favorably with other scoots in this area (XB series moreso than tubers, natch) |
