BMX - mid bb install problem

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View Full Version : mid bb install problem


mx_599
12-18-06, 12:16 AM
hello everyone, i was pressing my bearings into my bb shell and it seems like the spacer that goes between the two bearings is too long?? the two bearings will stick out on each side 3-4 mm probably and they will not be seated against the machined stops of the bb shell.

is all this normal? it doesn't seem right. do i need to cut the spacer? and that's messed up because it is not going to be easy to cut the thing square AND the precise length it needs to be to allow bearings to be seated in shell and supported by spacer.

:(


eightdip
12-18-06, 04:07 AM
What bb is it? The primo one is meant to stick out

mx_599
12-18-06, 10:33 AM
What bb is it? The primo one is meant to stick out
Fit bb kit for 22mm spindle to go in a Standard frame


KinetikBiker
12-18-06, 11:13 AM
You don't have to use the inner spacer, just don't make sure when you are tightening them they are tight, but not so tight that they feel unsmooth or don't move with a push or whatever...

And i'm sure a local bike shop will have the inner spacer if you want it...

mx_599
12-18-06, 11:46 AM
You don't have to use the inner spacer, just don't make sure when you are tightening them they are tight, but not so tight that they feel unsmooth or don't move with a push or whatever...

And i'm sure a local bike shop will have the inner spacer if you want it...
thanks!
well i don't know about not using the spacer. it wouldn't be proper if there is a lot of clamping force with the cranks. i am using wombolts. is there a lot of force with these? i also don't think it would be correct to not snug the wombolt down as directed. if you leave it slightly loose to accommodate the lack of spacer you will most likely damage the crank interface.

i swear, nothing can ever go smooth. i thought these mid bb kits were universal. now its like i need to cut a spacer to length. i did call standard today and they said i need a 46mm. i am going to ACE to investigate the use of PVC pipe. this will be far easier than metal for me to get square and precisely 46mm.

no local shops, all mail order.

please, any other comments, or follow-up comments to the above?

KinetikBiker
12-18-06, 11:51 AM
i swear, nothing can ever go smooth. i thought these mid bb kits were universal. now its like i need to cut a spacer to length. i did call standard today and they said i need a 46mm. i am going to ACE to investigate the use of PVC pipe. this will be far easier than metal for me to get square and precisely 46mm.

no local shops, all mail order.

please, any other comments, or follow-up comments to the above?
I don't know if the Wombolts would produce more stress on the bearings without the spacer, but i don't think they would. I don't use the spacer with my cranks, and they work fine. I have a 22mm fit mid bb and Primo hollowbite cranks.

The reason why the spacer is too long is because you probly got it from an american bb where the cups would make more space inbetween the bearings, leaving more room for a longer spacer...

And i'm sure if you called the mailorder you like they can send you a proper spacer if you specify the bb, frame and crank combo.

sbcdestroy
12-18-06, 09:06 PM
YOU DO NEED THAT SPACER... it keeps the bearings from binding, and exploding faster....

****...

you might want to find a smaller one, or trim yours NEATLY...

but dont run them without it for too long.

KinetikBiker
12-19-06, 06:47 AM
YOU DO NEED THAT SPACER... it keeps the bearings from binding, and exploding faster....

****...

you might want to find a smaller one, or trim yours NEATLY...

but dont run them without it for too long.
Plenty of people don't use that spacer...it somewhat helps to stop ghost pedaling without having your chain hella tight, therefore putting alot of stress on your more expensive driver/sprocket. Just don't crank the pinch bolts too hard.

mx_599
12-20-06, 09:50 AM
update:

not to worry guys, used a pvc pipe for for a perfect 46mm fit. in the process, i managed to save some weight on my build.

Quick_Torch C5
12-20-06, 10:19 AM
Nice Mcgyvering!:D I'm all about DIY! Please let us know about the longevity of your homemade spacer!

KinetikBiker
12-20-06, 11:25 AM
Nice Mcgyvering!:D I'm all about DIY! Please let us know about the longevity of your homemade spacer!
Yeah! I'm interested to see how well it works.