Replacement crank clearance on chainguard

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baldwooky

baldwooky

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Was planning on swapping my cranks from the Coaster to the Ultra Glide and picking up a 3 piece profile set for the Coaster, which I took the chainguard off, so theres no interference issues on that, however I was out on a ride over the weekend, and one of the pedals got banged and managed to reverse thread itself out of crank, stripping the threads in the process. It was a fun ride home..



Didn't work. 8 miles back with 1 pedal on a stretch was an adventure.

Anyways, now I need to get 2 cranksets for cruisers, without a chainguard, there is obviously no issue fitment issues, but with a chainguard, am I going to be limited with what cranks I can run? Is there something I should be looking for? I see no measurement when trying to buy them, and I don't really care to spend $150+ on a crankset to find out they won't fit if you know what I mean. Other than pulling some off of other bikes with chainguards already, how can I know if they fit?

(lack of other cruisers with chainguards currently, means I have to source new cranks)
 
What kind of 3pc setups do you plan to run? If they're square taper, make sure that you use a wider (112mm+) bottom bracket, and a crankset that allows for the sprocket to be mounted on the back-side of the spider. To illustrate, I needed clearance for the chainguard on Chango (before I gave up on using it), so I took the chainring from the front of the spider:
and mounted it to the backside of the spider:
If they're BMX 3pc cranks, then you should have plenty of room, and can shuffle the spacers around to put the arm at the proper distance from the chainguard.
 
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I was hoping to run 170mm profile racing bmx cranks, which are 68? Spline not square tapered, with sealrd bearings, no spider/ring setup just a chainwheel, at least on the coaster (no guard)

But I would also like to know if a standard 1 piece off of a GT/Dyno bmx would work without buying 1 to try lol.
 
1 Piece piece cranks are pretty standard. You probably will have to trial and error to find the right 3 piece or find someone who has done it. You could also bent the chainguard a little for small rubs.
 
So, took some measurements of bikes I have currently. a 1 pc off a Dyno BMX is about 30mm closer to the chainwheel, a 180mm Profile 3 pc is about 25 mm closer, so most definitely 1 pc are not a standard, and 3 pc cost a way too much money to buy and try.

There has to be some sort of measurement or style/term of cranks that are made to be used with chainguards?
 
Also, I don't understand how you would use spacers to get the crank arms out further on a 3 pc? The spacers go on the threaded portion, and can be used to move the chainwheel, but don't the crank arms attach to the spindle, in whatever taper pattern there at the end and that's what you get.

I suppose you could get a longer spindle to solve the issue, but I'm not sure if that's possible for all cranksets.
 

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