Author Topic: Chain Speed  (Read 3499 times)

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Offline SPARKY

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Chain Speed
« on: March 23, 2008, 02:20:37 AM »
You bike guys and Transverse Axel  folks---what kind of chain speed are you dealing with??????????
Miss LIBERTY,  changing T.K.I.  to noise, dust, rust, BLUE HATS & hopefully not scrap!!

"Security is mostly a superstition. It does not exist in nature, nor do the children of men as a whole experience it. Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure or nothing."   Helen Keller

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Offline Sumner

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Re: Chain Speed
« Reply #1 on: March 23, 2008, 10:18:48 AM »
Sparky here is a quote from this build page..............

http://purplesagetradingpost.com/sumner/bvillecar/construction%20page-42.html

......... on my site.

Quote
In the middle of making the motor mounts I started on the idler sprocket for the chain drive. I found a couple idler sprockets on the Internet, but couldn't really find what rpm's they were good to. In the process of figuring the rpm this idler might spin at I quickly became aware of the tremendous speeds the chain travels at in high speed bikes and cars. I figure that this sprocket will be spinning at anywhere between 8000 to 11,000 rpm depending on the speeds I'm hoping this car will eventually reach. I research sprockets as best I could on the Internet and then called MRC and talked to a tech guy and came up with the double shielded bearing, shown below, that is good to over 14,000 rpm. There is more on the sprocket and bearing and where I got them on ( THIS PAGE ).

I don't know what I did with my calculations, but I just did a quick re-figure and if I didn't screw the math up I figured that with the 7 inch dia. rear sprocket I have on the car right now if it ever went 230 mph the chain speed would be 90 ft./sec.  Using the info in the quote and the size of the idler sprocket I made the chain speed could be up to 166 ft./sec, but I forgot what the target mph was in that case.  Anyway maybe some of the guys that have gone really fast like Rick or Kent or Mike would like to comment here.  I'll bet there chain speed are tremendous.

What type chain or you thinking??  I would think the chains in transverse axles would be different that bike chains and more like a timing style chain.

c ya,

Sum




Offline Stainless1

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Re: Chain Speed
« Reply #2 on: March 23, 2008, 10:23:39 AM »
ours is about 97 MPH if I did the math correctly...
1 inch per link, 26 links per tire revolution, almost 62 inch tire circumference, 230 MPH tire speed
All numbers are approximate, without all the decimals...  :roll:
Stainless
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bak189

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Re: Chain Speed
« Reply #3 on: March 23, 2008, 11:17:10 AM »
Most of the fast M/C streamliners, spray water on the chain at speed.........also use O-ring
chain.....that's what I have been told.................

We have not gone fast enough to worry about
chain speed.......Yet

Offline narider

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Re: Chain Speed
« Reply #4 on: March 23, 2008, 11:19:46 AM »
I always look at our timeslips to see how fast our chains go.  :wink:
Granted the chain stays on the bike  :roll:
Todd

Offline panic

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Re: Chain Speed
« Reply #5 on: March 23, 2008, 11:22:02 AM »
The bearing might take it, but the chain is another matter.
None of the bike chains I see are within industrial etc. guidelines for speed - all turn much faster.
Using known-safe figures (2500 f/m engine speed for sustained cruising) a 24 tooth #428 (1/2" pitch) engine sprocket @3,780 RPM (H-D 74 engine) is 3,791 f/m (43 mph) based on the pitch diameter - even this is off the scale according to the guides, but H-D has used this since 1936 with the same sprocket and chain (no recall, no failure, no odd service needed), so I assume it works.
What happens if you double that? Nothing good; the centrifugal force moves the rollers up from the root and they drive higher up on the tooth than intended, and also increase the pitch so the number of teeth properly engaged is down. However, again, for racing this seems to work (8K RPM doesn't break the chain frequently).

If the sprocket shown is 36 #50 (530), yes? 1 turn is 1.877 feet of chain, so its RPM × 1.877 = f/m, multiple by .0113636 to get mph.

bak189

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Re: Chain Speed
« Reply #6 on: March 23, 2008, 12:00:09 PM »
I don't know about all these number......but
back in my "old" roadracing days with a Norton Manx (with maybe 50 hp) we ran it on the "again
old style" Dyno.........and we put a strobe-light
on the final chain...........and what it showed
would scare any one..........that is why we run a
BIG and STRONG chain guard on our equipment..