Chinertown

Other Resources => Maintenance, Mechanics, & Tools => Topic started by: catenaccio on April 23, 2025, 03:13:05 AM

Title: ZTTO pressfit BB, how to uninstall?
Post by: catenaccio on April 23, 2025, 03:13:05 AM
Hi, I purchased a ZTTO pressfit BB for my VB-177 frame, is this one: https://es.aliexpress.com/item/1005005940645297.html?spm=a2g0o.order_list.order_list_main.28.63fd194dZeYY6y&gatewayAdapt=glo2esp

To install, is as simple as pressing one side into the frame, and then just screw the other side that will come into place easily, but.... how to uninstall?

I mean, is it supposed to unscrew a little bit each side taking turns until both side are out?? Because if I try to extract it with pressfit BB tools only bearings are coming out
Title: Re: ZTTO pressfit BB, how to uninstall?
Post by: Serge_K on April 23, 2025, 03:19:30 AM
Hi. You extract it with that: https://es.aliexpress.com/item/1005005896124123.html (the oval bits).
This tool is cheap, and works great.
Title: Re: ZTTO pressfit BB, how to uninstall?
Post by: catenaccio on April 23, 2025, 03:37:00 AM
Yes, I already have that tool.

But the issue is both sides of BB are screw, so to uninstall them you have to unscrew, and at the end one side still will be into the frame, so if I try to extract it with that tool, only bearings are coming out.... what I am doing wrong?
Title: Re: ZTTO pressfit BB, how to uninstall?
Post by: Serge_K on April 23, 2025, 05:23:25 AM
That's what the oval bit is for. You put it inside the frame, behind the BB cup you want to extract. then you extract the cup. Check out youtube videos if you can't figure it out on your own. It is confusing that there are 30 different bits in the kit, but once you understand, you'll realize how trivial it is, just take your time. videos will help.
Title: Re: ZTTO pressfit BB, how to uninstall?
Post by: SirBikealot on April 23, 2025, 06:32:40 AM
shouldn't do "unscrew one side a bit and then press the loosend part inside to loosen the other side" do the trick? At least this worked quite well for me each time with this BB
Title: Re: ZTTO pressfit BB, how to uninstall?
Post by: ZacItaly15 on April 23, 2025, 07:28:27 AM
unscrew just a little, rubber mallet, unscrew other few millimeters, rubber mallet again...
For the last few millimiters just use your thumb...

I have the posted extractor but it's equally safe to use the rubber mallet.
Title: Re: ZTTO pressfit BB, how to uninstall?
Post by: catenaccio on April 23, 2025, 09:24:23 AM
unscrew just a little, rubber mallet, unscrew other few millimeters, rubber mallet again...
For the last few millimiters just use your thumb...

I have the posted extractor but it's equally safe to use the rubber mallet.

Great, ty guys, will try like this  :)
Title: Re: ZTTO pressfit BB, how to uninstall?
Post by: ZacItaly15 on April 24, 2025, 02:47:00 AM
reassembly after an appropriate cleaning and sanding
I applied white waterproof grease.
I used some baking paper (but you can also use plastic bag) between the external cup and the socket wrench in order to avoid any damage to the carbon frameset and to the external cup (I hate to see chipped splines in the bottom bracket)
I'm still uncertain how much force I need to apply when installing because the frameset bottom bracket is elastic and I don't want to over-tighten but neither to let the BB loose.