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Old 02-19-2018, 10:42 AM   #96
Weldangrind   Weldangrind is offline
 
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Join Date: Mar 2009
Location: Sardis, BC, Canada
Posts: 25,977
That very cluster came stock on my Lifan, but the speedo and the tach were wildly inaccurate. I installed the speedo from my Roketa (which is in miles, not km) and it is relatively correct.
There is a formula for selecting a speedometer, but I can't recall how it works. I think it's a reference to the rpm of the front wheel, taking the circumference into account. What I do remember is that 2240:60 means the speedo cable is turning 2240rpm at 60mph. Some metric speedometers reference 60km/h (about 35mph), so you'll occasionally see a ratio like 1344:60, which is identical to 2240:60.
If you choose to buy an eBay mechanical speedo, it would pay to first measure your front wheel circumference and Google the formula for speedometer calculation. Make a chalk mark between the right side bottom of your front tire and the ground, roll the bike forward one complete revolution and make another chalk mark. Measure the resulting distance between the chalk marks to determine the circumference.
Of course, the alternative is to buy an electronic speedometer and go the magnet route.
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Weldangrind

"I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer


 
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