Cranks feel like they have bit of slack like a freecoaster

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5/14/2016 6:29 AM

My profile racing cranks feel still move a bit when they are still very tight. When I pedal forward the left crank sometimes moves a bit like its jump a couple splines on the spindle? any solutions to what might be the problem? thanks.

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5/14/2016 7:38 AM

Do you mean they rock a bit? If so the splines are worn. Not much you can do about it, but if you take a couple of spacers out so it's further on the splines it might help.
You could also try to determine what's worn and replace it. It might just be the crank arm, or just the axle. It usually only happens if they've been run loose for quite a while.

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5/14/2016 7:42 AM

grumpySteve wrote:

Do you mean they rock a bit? If so the splines are worn. Not much you can do about it, but if you take a couple of spacers out ...more

Yeah, I have to loosen them to do crankflips so thats probably what's caused it, I think they're worn down on spindle and crank arm. I was looking at the BSD substance cranks but they are 22mm and I have a spline drive 19mm sprocket so IDK. Thanks tho!

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5/14/2016 7:44 AM

You shouldn't need to loosen them if the tube spacer is the correct length. Get more profiles, they're awesome.

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5/14/2016 9:00 AM

grumpySteve wrote:

You shouldn't need to loosen them if the tube spacer is the correct length. Get more profiles, they're awesome.

What do you mean the tube spacer? And I love doing crankflips so I need to slightly loosen the bolt to make them spin, but yeah I agree profile are awesome but the price of the spindles are not lol.

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5/14/2016 11:24 AM

LewyyM8 wrote:

What do you mean the tube spacer? And I love doing crankflips so I need to slightly loosen the bolt to make them spin, but ...more

this piece, goes in the bb shell in between the bearings and has to fit snug in between both the inner bearing races otherwise it won't do its job.

[LINK TO IMAGE]

If you don't have one, get one. If you have one, it's gotta be too short and not doing its job. You don't need loose cranks to do crankflips, my bolt is as tight as I could get it and my cranks spin insanely well because my tube spacer is the right length.

So get that sorted out, then try it. Running them loose might have ruined your cranks and work the splines out like Steve said… It could be the spindle splines worn out, but the splines in the crank arms themselves could also be work out too. If that's the case, they'll always have a slight shifting feel to them from now on even when tight (probably not as bad as they are now, but still)

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5/14/2016 11:26 AM

The spacer that goes between the bearings, they're often a touch too short, which is why you get extra spacers so you can adjust the length to get it right. Without that your cranks will feel stiff (and you'll ruin the bearings quicker), with the correct length they'll spin freely

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5/14/2016 12:50 PM

profiles are infamous for developing that, hence the term "profile wobble" both being applied to their cranks and hubs
get some 22mm 3pc cranks, 2pc are bad because if/when they develop wobble it is often on the conjoined crank/spindle and you cant replace just an arm

i recommend animal akimbos or odyssey thunderbolts \
screw profile

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5/14/2016 1:40 PM

grumpySteve wrote:

You shouldn't need to loosen them if the tube spacer is the correct length. Get more profiles, they're awesome.

LewyyM8 wrote:

What do you mean the tube spacer? And I love doing crankflips so I need to slightly loosen the bolt to make them spin, but ...more

sundaybmxRR wrote:

this piece, goes in the bb shell in between the bearings and has to fit snug in between both the inner bearing races otherwise ...more

Okay thanks, I will measure the distance between them and get one that fits perfect as mine doesn't fit snug, didn't realised it had to be like that :0

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5/14/2016 2:51 PM

I could simply be a loose sprocket bolt.
or worn spindle because of spline drive spocket maybe.

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5/14/2016 5:02 PM

LewyyM8 wrote:

Okay thanks, I will measure the distance between them and get one that fits perfect as mine doesn't fit snug, didn't realised ...more

If it's a bit too short, you can just add some small crank washers and that'll fix it. But yeah that's probably your issue then

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5/15/2016 12:02 AM

bmxsteve99 wrote:

profiles are infamous for developing that, hence the term "profile wobble" both being applied to their cranks and hubs
get ...more

The crank wobble only develops if they're run loose. And the hub wobble is from people not using the correct size bearings (although there was a batch of the ss/high flange hubs that were machined slightly out. Which could be fixed with a thin spacer). Profile use imperial bearings, there's a metric sized bearing that's almost identical but ever so slightly narrower. If you use the metric bearing it will wobble, and then people moan about their hubs wobbling.

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5/15/2016 12:38 AM

grumpySteve wrote:

The crank wobble only develops if they're run loose. And the hub wobble is from people not using the correct size bearings ...more

The hub wobble is from the bearing seats wearing out, Profile are definitely aware of this because they offer a special bearing to help with that which is .05mm

http://www.profileracing.com/estore/product.php?productId=129

"E. Oversized 6903-52RS (17MM ID x 30.05MM OD x 7MM W)
For Profile Mini, Totem, Elite and Fixed/Track Front Hubs as well as Madera Front Pilot and Madera Rear V-2 hubs.
Over time, bearing bores can possibly wear out from abuse and or high spoke tension. This bearing should (but not in all cases) solve that issue."


It happens, my old Demolition front hub was so bad that when it was laced up, I could easily pop the bearings in & out by hand.





You're right on the cranks though, running them loose causes the splines to wear out. Even just slightly loose sometimes cause my Animal cranks were always kept snug but still developed a small "shifting" feeling to them overtime which annoyed me so I just got Odyssey Thunderbolts which won't develop the wobble. If you keep your 48 spline cranks tight though, they should be just fine.

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5/15/2016 1:45 AM

That could be one cause. But I switched bearings in my hub and it wobbled with the new bearings. Switched back to the original ones and there's no wobble. Profile also make a thin spacer to cure it.
The problem is, most mini hubs out there have been around for years and people will moan when they wobble after buying them 5th hand. They first came out over 10 years ago, most people will swap hubs with someone within a year or 2 of owning them. So most of the wobbly ones are probably 10 years old.

I've only ever had one pair of cranks that wobbled. They were old worn out profiles I got cheap. But I've had 3 other pairs of profiles that never wobbled, and only one of those I got new.

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