Author Topic: Bottom Bracket inner tube spacer  (Read 3554 times)

Offline aliasdck

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Bottom Bracket inner tube spacer
« on: April 17, 2021, 08:52:28 PM »
I am going to build up my new frame this weekend. About to install the bottom bracket and I'm thinking of using the mod where you put a grip flange between the sprocket and bearing.


I've read through old posts about it but wanted to ask you guys to get a more modern consensus: Do most of you install the inner tube spacer between the bearings? It's important for the health of the bearings but I've seen that some people install without it because it reduces weight (but almost an negligible amount as the tube spacer barely weighs anything) and without it you can tighten things up more but this is not good for the bearings obviously. My cranks are profile with 48 splines and have compression bolts on the ends of the spindle. They are the profile mini magnutanium ones.



Offline Mambocowboy

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Re: Bottom Bracket inner tube spacer
« Reply #1 on: April 17, 2021, 11:09:18 PM »
I am going to build up my new frame this weekend. About to install the bottom bracket and I'm thinking of using the mod where you put a grip flange between the sprocket and bearing.


I've read through old posts about it but wanted to ask you guys to get a more modern consensus: Do most of you install the inner tube spacer between the bearings? It's important for the health of the bearings but I've seen that some people install without it because it reduces weight (but almost an negligible amount as the tube spacer barely weighs anything) and without it you can tighten things up more but this is not good for the bearings obviously. My cranks are profile with 48 splines and have compression bolts on the ends of the spindle. They are the profile mini magnutanium ones.



I've talked with mechanics I respect about this. It comes with the bb for a reason so I recommend using for the health of your cranks and bearings. By the way I love my 145mm magnataniums. Look great and very light of course.

Offline aliasdck

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Re: Bottom Bracket inner tube spacer
« Reply #2 on: April 17, 2021, 11:18:41 PM »
I went with 160's but might eventually try shorter down the road. I definitely think I'm gonna put the spacer in there, I always have, was just curious if it's common or not these days amongst riders. I don't think I'd want to risk the wear on the bearings.

Unfortunately the bottom bracket kit in the photo won't fit my new frame. I bought it because the specs on the page I I bought the frame from said "mid bottom bracket" but it looks like it's actually spanish. I'll email them and let them know they need to update it so this doesn't happen to anyone else.

So I've got to order a Spanish BB kit instead so I won't actually be setting up the new frame now, probably in another week unless one of the local bike shops happens to carry them around here. I'm gonna check tomorrow and if not then order one online.

Offline khe killah

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Re: Bottom Bracket inner tube spacer
« Reply #3 on: April 18, 2021, 09:29:47 AM »
The centre tube is to stop the bearings from being side loaded when tightened down.

Offline DaddyCool

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Re: Bottom Bracket inner tube spacer
« Reply #4 on: April 18, 2021, 10:36:30 AM »
Hello, I use these spacers for all my bikes. I assume it really makes sense for the bearings. The only reason not to use it would be to be able to make the crank spin less easy by tightening the bolts. But this can be done in many other ways. I never tried the grip flange version but I but some cut out plastic rings between the sprocket and the bearing and this follows the same idea. For me this works great.
I never tried it but assume that this is also a good idea:
https://www.vocalbmx.com/shop/vice-drs-bottom-bracket/

Offline aliasdck

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Re: Bottom Bracket inner tube spacer
« Reply #5 on: April 19, 2021, 08:19:41 PM »
Thanks for the advice guys guys, daddycool I'll check out that link. Just discovered I don't have any grip flanges laying around anymore (thought I did, must have thrown them out) so alternatives may come in handy

Offline metalbmxer

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Re: Bottom Bracket inner tube spacer
« Reply #6 on: April 19, 2021, 09:19:37 PM »
You can literally never install one of those and your bearings will be just fine. Also it makes a big difference in terms of weight bc some of them are made from cheap steel that is so much heavier than the alloy which profile uses. But still, there is zero benefit to running that spacer in there--been doing it for years
Dax (now in LAS VEGAS as of July 2022)

Offline DaddyCool

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Re: Bottom Bracket inner tube spacer
« Reply #7 on: April 22, 2021, 10:51:46 AM »
Hi metalbmxer, this is intersting to hear. Of course one should avoid the steel ones... I realised that over the years my titanium spindle is worn a bit so I need to tighten the bolts  a little more to have the arms fixed (I can remove them by hand now when I disassemble the crank). So I assume that the bearings would have a high side load when I would not use the tube spacer. But I never tried because the aluminium spacer for a normal 19 mm Spanish BB which I use weighs 16 g only...

Offline smsabb

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Re: Bottom Bracket inner tube spacer
« Reply #8 on: April 26, 2021, 09:23:30 PM »
I install them on my bikes ,I had to cut down a kink bb spacer to fit my big daddy .I now have enough r12 bearings to last me the rest of my life but I like having the spacer in there .

Offline mal

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Re: Bottom Bracket inner tube spacer
« Reply #9 on: April 27, 2021, 11:41:41 AM »
I wouldn't skip it.They wouldn't add an extra cost if it wasn't needed.

One plus for installing it is that you can really tighten the crank bolts without worrying about messing up the bearings.

If you want to skip it for tightening the cranks so they don't move you can just install the washer and trim it a mm more than needed,you will have the same result but with safety.Wouldn't do that either.Best way to do it is with the Vocal DRS.

The weight of the washer is laughable,if you get to the point that you count such weight differences start thinking about removing the paint from your frame and parts,you could save 100 more grams if you raw your whole bike!
 
« Last Edit: April 27, 2021, 11:56:02 AM by mal »

Offline Mambocowboy

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Re: Bottom Bracket inner tube spacer
« Reply #10 on: April 27, 2021, 10:15:50 PM »
I wouldn't skip it.They wouldn't add an extra cost if it wasn't needed.

One plus for installing it is that you can really tighten the crank bolts without worrying about messing up the bearings.

If you want to skip it for tightening the cranks so they don't move you can just install the washer and trim it a mm more than needed,you will have the same result but with safety.Wouldn't do that either.Best way to do it is with the Vocal DRS.

The weight of the washer is laughable,if you get to the point that you count such weight differences start thinking about removing the paint from your frame and parts,you could save 100 more grams if you raw your whole bike!
My spacer is super light.

Offline metalbmxer

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Re: Bottom Bracket inner tube spacer
« Reply #11 on: April 28, 2021, 02:39:22 PM »
Running the spacer is a JOKE plain and simple. I kept my cranks super tight and haven't had one single issue for YEARS. Not to mention 95% of the time the fit is wrong and either too far out or not doing anything at all
Dax (now in LAS VEGAS as of July 2022)

Offline aliasdck

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Re: Bottom Bracket inner tube spacer
« Reply #12 on: May 01, 2021, 06:27:07 AM »
The damn spacer ended up being a few mm too short. Didn't realize until after I had already pressed everything in. Its just not long enough so the fact that it is in there now is pretty much pointless. The bottom bracket kit I bought was intended for shell width of 68mm but the frame I have uses 73mm. I did not not even know there two shell widths possible when dealing with Spanish bb otherwise I would have checked beforehand.

I'm starting to get angry. Too many of these mistakes have already happened just in this one build because companies don't provide a full set of specs with their products. WTP has not posted that the frame has a 73mm length shell. Deco, the company that made the Spanish bottom bracket kit, did not specify if it was intended for 68 or 73 either, only specs provided were that it was Spanish, for 19mm spindle and the weight.

WTF! To all companies making bmx parts: PLEASE start providing a full range of specifications for your parts so that consumers know exactly what they are buying. This is so damn important, why should I, as a consumer, even have to ask for this? What kind of half ass job are most of the companies doing? I'm spending my hard earned money here, it is not too much to ask that they present their products with pride and professionalism?

Ok - rant over. I've put everything together and it's working well without the proper spacer inside but I've made sure not to tighten it too much. If I don't have any problems, like if doesn't keep getting loose or any other problems then I'll probably just leave it. Otherwise I'll get a proper spacer, pull one bearing and swap it. So far I don't think this will be necessary though.

Offline DaddyCool

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Re: Bottom Bracket inner tube spacer
« Reply #13 on: May 01, 2021, 12:23:52 PM »
WTF this is really sh*tty! I only knew about different widths of Mid BB shells. I once bought a Mid BB from Stolen for my Tango frame and here it was stated clearly: Use the spacer like it is for 68 mm, use the additional 5 mm spacer for 73 mm. That was how it should be!
So one thing you can keep in mind at least: If you want to remove one bearing to make it correct, you don't need another spacer but only a 5 mm washer (better measure the exact size). You can use here some of the washers that is meant to be installed on the outside between the bearing and the crank arm. In most cases I had some left. This would at least avoid the need of buying something new.
I can fully understand your frustration. Sorry for this.

Offline mal

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Re: Bottom Bracket inner tube spacer
« Reply #14 on: May 01, 2021, 04:18:36 PM »
Ι fully agree about the lack of specs info.

Its like some bmx ''companies'' run their business like they live in the basement under their parents house..

Good idea from DaddyCool,this should work.You can stick them to the long washer with some thin tape.