Bikeguide.org - Bike maintenance for BMX'ers
The Street => The Bike Shop => Topic started by: blueee on July 22, 2018, 02:16:37 PM
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im looking into buying some 24mm fit indent cranks.
theyre on sale for cranks + sprocket for $150 and theyre overall about 2oz lighter than my twombolts.
but my main concern is that the they have been out for a while, no one is buying them and they will soon stop producing 24mm mid bb's
should i buy them anyways?
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im looking into buying some 24mm fit indent cranks.
theyre on sale for cranks + sprocket for $150 and theyre overall about 2oz lighter than my twombolts.
but my main concern is that the they have been out for a while, no one is buying them and they will soon stop producing 24mm mid bb's
should i buy them anyways?
People always say how the bearings don't last.
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It seems like there is a lot of companies using them. Seems doubtful they would cease production.
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i see how 100 dollar cranks can be atractive. However you can clearly see how bearings on 19 mm cranks get murdered after a few years of use. Can't say the same about 24 mm cranks and smaller bearings.
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I rode spanish 22's for 10+ years and only broke two bearings. I'm light on bearings
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You shouldn't be breaking them at all
150 bucks to save 2oz of non-rotating weight in the centre of mass of your bike... Save your money
Edit: Not to mention you won't have a concentric sprocket anymore, one of the underrated things Wom/Twom/Thunderbolts do
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You shouldn't be breaking them at all
150 bucks to save 2oz of non-rotating weight in the centre of mass of your bike... Save your money
Edit: Not to mention you won't have a concentric sprocket anymore, one of the underrated things Wom/Twom/Thunderbolts do
What does the concentric sprocket thing mean, if you don't mind explaining?
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Concentric means perfectly centred. Wombolt family achieves this by having an interference (press) fit for the sprocket, instead of a slip fit
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and what are the amazing advantages a concentric sprocket provides?
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Have a think about it when the mef wears off
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Teasing you in retaliation for being cheeky aside, I'll tell you what it does. It's nothing super amazing, and it doesn't even benefit me as I run my chain intentionally loose for crankflips and for a bit of extra time to start pedalling backwards in fakies
What it does is go a big way to minimizing tight spots in your drive train. Imagine running a slightly oval sprocket instead of a round one. Every 180' you are going to have a tight spot, and 90' from that a loose spot. Slip fit sprockets, particularly when paired with a slip fit hat washer (which isn't always the case) will make the sprocket sit a bit eccentric (off-centre), causing a similar effect (except every 360' instead of 180')
This is only really an issue if you tension your chain, but a lot of people in BMX do exactly that, particularly in racing to reduce wasted effort in pulling the chain taut before it actually moves the driver
In freestyle a lot of people wouldn't care or notice. But it is a clever bit of engineering that does have some effect. Wombolt family got a bit of a bad rep early on, but George did some clever things like this. Another clever thing was the spindle -> non drive side arm joint - it sets a proper preload (Edit: something very problematic with spline interface cranks like Profile) without having to rely on pinchbolts