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Technical & Reference Section => Tech and Restoration => Topic started by: jezza on December 08, 2006, 12:21 AM
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Ive got a 400 flight crank 180mm and trying to fit on a DP freestyler frame, the left arm is virtually touching the chainstays, do i need 175's or am i doin summert wrong.
never fitted 3 piecer beforev :crazy2:
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You need to put spacers between the crank arm and the BB, you should have some spacers with it :daumenhoch:
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no spacers boooooooooooooo can i buy/make em :-[
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no spacers boooooooooooooo can i buy/make em :-[
don't make them out of chocolate. in the summer they melt... :crazy2:
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the washers should be readily available @ any hardware store B and Q
if not vert ego might have them
V
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the chainwheel side is fine, but the other side is too close :-\
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oh i see
flights brand new come with about 5 or 6 spacer washers often lost over the years
all bar 2 of them (i think) are differing thickness
i reckon bored out penny washers would work
saying that i,ve not tried it meself
trial and error best way :daumenhoch:
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Are you sure you can fit spacers to 400s? 401s and profiles, sure, but aren't 400s on a square tapered spindle? (like a MTB or road bike?). Theyre the ones without a pinch bolt, right?
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correct, ive tightend it all up and there is about 1mm clearance on the opp side to the chainwheel, would 175's be better?
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If its the square spindle, with a fixed bearing shoulder on the chainring side then I dont think there is anything you can do. 175s might help a little (have you got a big stash of 400 arms?) but another fix is to put a small dent in the chainstay. It sound drastic but I have done it loads of times (for crank arm clearance and also for chainring clearance). I just put an old tube or bar across the stay and then hit the bar with a hammer, making a nice rounded dent in the frame stay. Some frames even come with this dent pre done.
Another idea is to make new BB cups that seat the chain side bearing further inside the frame (Im guessing they are sealed bearings), moving the whole assy over to the left. This could be a bit of a pain and would only work if you have loads of clearance on the right side.
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Are you sure you can fit spacers to 400s? 401s and profiles, sure, but aren't 400s on a square tapered spindle? (like a MTB or road bike?). Theyre the ones without a pinch bolt, right?
This is right, have you got a photo, so we can see what is going on, it could be that you have put the spindle in the wrong way round.
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I think that 400s have the same spindle, and work in the same way to DB Leary Turbo cranks (the cro-mo ones, not the ally turbo lite ones).
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SamAlex,
You're absolutely correct the spindle is the same on the HL Turbo and the 400's, also I think the early Haro cranks too.
It maybe that the spindle should be switched from the side it is on at the moment but if that does not cure the problem then it is shorter cranks! 175 400's are rare though!!
Paul
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Ah yes, its all coming back to me now. I had about 4 or 5, 400 arms (some redline and some sugino stamped) and they were all 180s. I was in my early teens so they were a bit long but they were "flights" so I made do. The thing is, I have no idea where they came from ... or where they went!
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Shame because I am looking for an orphan arm (not sure if redline or sugino yet - still awaiting delivery).
The 175's came as stock on the laserlite, but the tests always suggested changing to 180's!
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thanks guys your input is appreciated :)
i have the spindle set up with the threaded side on the opposite side to the chainwheel, i thought as 1 piece cranks are that way i assumed 3 piece ones were the same
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I always built the ones I had like you say: Chain ring on the right, lock nuts on the left.
As the arms just sit on the taper and stop way short of the bearings and lock nuts I cant see it making a diference what way the spindle is, as long as it fits.
Good luck with it.
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Jezza,
I think the way you have installed them would have given you the most clearance, but it may be worth reversing before going down the new crank route!
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ive had a thought ::)
im going to manufacture a square washer to fit inside the crank arm about 2-3mm should do the trick, the bolts are long enough to cope with this so fingers crossed, ill let you know
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You could use "Ally taper shim". You know, the one that comes free with every can of coke. Wrap some of the can round the spindle in a cone and then crush it into a square with the instalation of the crank arm. It works when the square on an ally arm is opened out and might be easier than making a washer.
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Nice Alex the old coke can trick eh.... takes me back
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http://cgi.ebay.com/OLD-SCHOOL-REDLINE-FLIGHT-BMX-CRANKS-175MM-SINGLE-BOLT_W0QQitemZ270062985838QQihZ017QQcategoryZ64644QQrdZ1QQcmdZViewItem
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those are 401s. that have a straight spindle, hence the pinch bolt. 400s have a square tapered spindle and no pinchbolt
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i get my 3 piece washers from marine engine outlets , they do bronze washers that look rad