Shimano Hollowtech II Bottom Bracket Installation - BB-MT800

[@Harari_]

I never changed a bottom bracket and I was sure that It’s easy and I know how to do it. I was right, it is very easy, but it’s one of those videos that you are watching just to b sure that u r doing it correctly and I love them. This video showed EVERYTHING that u need to know and covered every little step that someone might just want to b sure about before he’s going to the next step even if he is 99% sure that he done that right. LOVE IT.

[@vanguardcycles]

I'm so glad! I really try to give as much information as possible, really happy it was helpful and well done on doing it yourself 😀

[@bs2592]

My sons crank is very wobbly. Does it mean the BB is broken or just needs tightening? Also, where do I get the tightening tool from?

[@ReValveiT_01]

The tool costs 35% MORE than the BB itself. Brilliant.

[@vanguardcycles]

Other (cheaper) tools are available for sure. It's often a good idea to pool funds with friends or local club members and collectively buy quality kit that will last for years for common jobs like this.

[@HeadBassVTEC]

Shimano tools are way too expensive, maybe a little overkill for hobbyist to use them once a year or less, for shops probably Shimano and ParkTool are worth the price there are cheaper but still decent quality alternatives for almost everything, I got Heppe BB44-16 for $11 (basically a cheaper copy of Shimano TL-FC33) and looks good enough for my needs and allows me to use ratchet or torque wrench (also have a digital torque meter which I can use for reverse threads)

[@ilya.aleshkov]

Thank you for such a detailed description! I go back to it every time I need to remove or install my bottom bracket. But it's only now that I notice you've flipped over the position of the sleeve )

[@vanguardcycles]

I'm really glad it's so helpful! Quite right there's the sleeve error, just shows none of us are perfect I guess 😀

[@thawnhatzaw2343]

Super helpful video that covered everything you need to know. Thanks a lot. I took apart and serviced my BB using this video and others on youtube (Park tool, made to cycle and made good bikes). It went smoothly and was easier than I thought. Keep making videos they're very helpful for budding home mechanics!

[@vanguardcycles]

Really glad it helped! Also if there are any other topics you'd like to see us cover, please let us know 😀

[@ferruccio4531]

that was really helpful, really liked the way you explained things. thank you

[@bigpimpinbig1]

Best video out there. Thanks for the great details. Decided to invest in a decent torque wrench for this. I wouldn't have thought of getting one that can measure torque counter clockwise without you mentioning it! It really helps you mentioning the tools in the description - e.g. the adapters for the BB tool.

[@vanguardcycles]

So glad it helped out - my motto is that every day is a learning day :) Are there any other jobs or tech you'd like us to cover in the future? Ride safe!

[@marcdarwin]

Thanks, great video, just changed mine now.

[@Blades-fm6ck]

Quality video, clear explanation, cheers

[@vanguardcycles]

Glad it helped 😃

[@Hootyhoo-jq9vq]

Wow! Excellent video. Thank you.

[@IIISentorIII]

Excellent video, thank you for that. And it's always nice to see fellow members from the collective.🟢

[@dominicpayne4393]

Thank you so much dude. Much appreciated

[@vanguardcycles]

You're super welcome 😀

[@HeadBassVTEC]

still deciding whether I should replace my BB, doing overhaul on my 15 old bike (not many miles ridden, less than 1000 miles for sure) the old one still spins pretty smoothly, got a spare new BB-MT501 that should be a replacement for my old M542 crankset

[@vanguardcycles]

It's worth taking the crankset out anyway, then you can have a good feel of the bearings with your fingers to see if it needs replacing

[@HeadBassVTEC]

@@vanguardcycles thx for reply and advice, might do that, but probably once I take the cranks off I will install the new BB already just to see how brand new BB feels for future reference ;o] I already upgraded my brakes (from Magura Julie that were impossible to bleed) to BR+BL M6100 with Magura Storm HC rotors and ZTTO ceramic finned pads, shortened both hoses and bled the system, serviced front hub and put new ball bearings in, and today finished servicing rear hub and putting new ball bearings in, including servicing and new balls inside the freehub will also install a new chain which I got (sram pc971) although the old one still shows me just little over 0.25% wear, but since I already have a new one and want a fresh clean one and wanted the chain links for easier cleaning and maintenance been learning about bike servicing for the last two months and ordering parts and tools thanks to great people like you anyone handy enough can do it with the youtube help for sure I would not be able to do it without the help from youtube (for example the freehub shimano no longer sells the Y3A398020 part and they consider it replacement part so they don't have exploded views or dealer manuals for it)

[@HeadBassVTEC]

@@vanguardcycles thx for reply and advice, might do that, but probably once I take the cranks off I will install the new BB already just to see how brand new BB feels for future reference ;o] I already upgraded my brakes (from Magura Julie that were impossible to bleed) to BR+BL M6100 with Magura Storm HC rotors and ZTTO ceramic finned pads, shortened both hoses and bled the system, serviced front hub and put new ball bearings in, and today finished servicing rear hub and putting new ball bearings in, including servicing and new balls inside the freehub, also cleaned and lubed the derailer cogs will also install a new chain which I got (sram pc971) although the old one still shows me just little over 0.25% wear, but since I already have a new one and want a fresh clean one and wanted the chain links for easier cleaning and maintenance been learning about bike servicing for the last two months and ordering parts and tools thanks to great people like you anyone handy enough can do it with the youtube help for sure I would not be able to do it without the help from youtube (for example the freehub shimano no longer sells the Y3A398020 part and they consider it replacement part so they don't have exploded views or dealer manuals for it)

[@LFMC1]

That's rocket science!

[@sufyanm4661]

When tf did they change the tool and why is it so hard to find the right tool without videos like this. I’ve been using Shimano bbs for years and now all of a sudden my bb wrench is useless so I have to wait 3 more days and pay more shipping to replace my seized BB. Nice one shimano

[@vanguardcycles]

I know, it's really annoying. There's also a different tool for road Dura-Ace too!

[@sufyanm4661]

@@vanguardcycles ah well, I caved and bought an adapter, at least I have a spare bike for now, but I was planning to go for a ride tomorrow haha. First world problems

[@RosClan97]

thank you!

[@vanguardcycles]

You're welcome! 😀

[@julioscioville2308]

Excellent

[@vanguardcycles]

Thanka very much 😀

[@khadijakhair591]

Good thank you

[@vanguardcycles]

You're welcome!

[@Gleeleeglee]

On video you had L and R cups opposite of the plastic tube? 3:30

[@vanguardcycles]

Aha well spotted! I had taken it apart so many times for the video but I didn't re-shoot the footage 😀

[@SgtJoeSmith]

thats what i just noticed too

[@gregmoxham2120]

@@SgtJoeSmith They are interchangeable but you're right, they were switched. They didn't go in the bike like that, even though it shouldn't make any difference. Good spot!

[@franciscomartins5260]

what is the difference between BB-MT800 and BB-MT801 ?

[@charliepizarro9450]

This gives me the confidence to tackle it myself. One question: my crankset specs show two figures for bottom bracket shell width: 68mm and 73mm. Does this mean there's a range? I'm replacing an existing BB with the same one, so I'll replicate the two spacers already on there, but I'd like to understand the numbers. Thanks for this excellent guide to the process.

[@vanguardcycles]

Really glad to have helped! You're quite right about the sizing. If you check the BB Dealer Manual, for example - si.shimano.com/en/pdfs/dm/MDFC001/DM-MDFC001.pdf - you'll see on page 11 the spacer setup is illustrated. Let me know if you need any more advice 😀

[@charliepizarro9450]

​@@vanguardcycles So they're saying that BBs generally come in two widths, and they're giving you info for both. Now I understand why we should measure. Makes perfect sense! Thanks from Oakland, California, for your excellent video!

[@vanguardcycles]

Yep that's right. Well, in fact cranksets and bottom brackets come in lots of different widths, so it's always best to measure. I'd also say if you're working on a used bike, it's always worth checking the setup with spacers etc, as they aren't always installed correctly!

[@KOL630]

What’s the purpose of the spacer? How do you know if one is required if you don’t have any paperwork on the crankset? I have grx cranks going into a Ritchey outback frame. Thanks. PS nice video.

[@nestessary]

Trial and error, otherwise just google your make/model and check the size. Good chance it’ll be 68 or 73mm so add spacers accordingly ig

[@vanguardcycles]

The spacers are used to ensure correct fitting, chainline etc. Start by checking the width of your BB shell. Then go to si.shimano.com and search for the model no. of your crankset and open the DM (dealer manual). This should have the BB install instructions and confirm the exact spacer setup for your BB shell width.

[@8bitoperator]

Since the base of this grease is lithium, can it react with aluminum? I meant Mobilgrease XHP 222

[@vanguardcycles]

Quite genuinely in this application, and with a quality stable grease, it really isn't an issue at all. However you could also use a copper anti-seize or something like Park Tool ASC-1, which I believe is aluminium-based.

[@stevebennett3587]

Can i run this bottom bracket with my shimano M5100 deore crankset🤔and if so, what spacers would i need for 12x148 boost spacing on a 1x10 deore set up please sir👍

[@vanguardcycles]

The spacers you need depend on the width of the bottom bracket shell (of the frame). Your crankset works with this BB, but the cranks need to be the 148 Boost version if that's your setup.

[@chiefengineer6288]

a good video will show the dissasembly as well. Good video it you buy a bike without a crank....

[@vanguardcycles]

Ah we've got videos showing both removal and installation of HTII cranks on the channel. Removal is here: kzbin.info/www/bejne/iKPHp5x_ebZ_hKc Assembly is here: kzbin.info/www/bejne/h52ZknmZhc6JetE Hope this helps!

[@namdarbolour9890]

Does greasing the threads defeat the purpose of the white compound we see pre-applied at the factory on the threads of the bearings?!

[@vanguardcycles]

That's a good point. Whilst things like factory-applied thread lock can help prevent corrosion, in real life a good coating of quality grease or anti-seize is much better. The cups are torqued so high in the frame that they are very unlikely to loosen. In addition, in British threaded (BSA) frames the thread direction coupled with the precession gives a "self-tightening" effect. The key is to prevent the cups seizing, especially if you have a steel frame.

[@kayasper6081]

The spacers remain a total mistery. Nowadays Shimano only mentions a QR code because they are "going green". However, I get completely lost on their website. So, with a 68 mm bracket, coming from a square crank set with a 50 mm line, what spacer should be mounted where?

[@vanguardcycles]

I agree it can be a bit convoluted! If you go to si.shimano.com and enter the model of the part - in this case bb-mt501 - you can search for the "DM". The DM is the dealer manual, with all the installation info. For a 68mm BB shell (the bike frame) and a normal mounting front derailleur, it's 1x 2.5mm spacer on the left and 2x 2.5mm spacers on the right.

[@kayasper6081]

@@vanguardcycles Thank you sooo much!!! To be honest, I have been on that Shimano website with the QR code this morning when I started the struggle. But I get completely lost on their site, just like now when I tried it again. But, since you are so friendly to say where the spacers normally should go, I just do that. And you're right, I have the BB-MT501. Thanks again, you really helped me out! New subscriber here.

[@vanguardcycles]

@kayasper6081 you're super welcome! I really do need to do some more videos, if there are any topics you'd like to see, please just say!

[@David-on1mr]

Shimano says 2 drive side 1 left side for a 68mm shell

[@bonifacioivcomilang1038]

Hi good evening do have a video of how to remove the bearing fron the bb?know the size of the bearing?

[@vanguardcycles]

Hiya! Unfortunately Shimano specifically state that the bearings shouldn't be removed from their BB cups, so I don't have that info.

[@AnotherMrLizard]

They’re integrated into the cup on most. Get a hope 24mm bb then it’s just 2 mr2437 each time.

[@Mrpablotortas]

what's the difference between BB-MT800a and BB-MT501 beside the installation tool?

[@vanguardcycles]

The BB-MT800 is an XT level part, with better quality sealed bearings. The 501 is Deore level. Hope that helps!

[@tiggerlator]

Can i ask, why is the outer shell on the BB-m800 smaller? I just got a neww BB for my bird aeris and it was one of these, so had to get a new tool to fit it.

[@vanguardcycles]

Unfortunately I think the answer is "yes" or "because". There's a third size for Dura-Ace too...

[@shaknit]

I have an old trek navigator and the bottom bracket measures out to be 73x116mm cant seem to find any that size. Any suggestions.

[@vanguardcycles]

I guess you mean it's a square taper BB? (rather than something like Octalink). Shimano make a 73x118 BB-UN300 which may well be OK, it will probably make very little (or no) difference to the chainline. If it's a case of installing that vs. writing off the bike, I'd go for it. Hope that helps?

[@Gleeleeglee]

Is the threaded part of the mt800 aluminum/plastic?

[@vanguardcycles]

The cups are aluminium

[@chacmool2581]

Is the width of BB cups the same between Road and MTB?

[@AnotherMrLizard]

For shimano no they are slightly different.

[@vanguardcycles]

Ach there are so many options with Shimano, but usually you use the spacers to adapt a BB for different frame widths

[@vitocho12345]

What is the width of the BB-MT800?

[@vanguardcycles]

It's for 68mm and 73mm BB shell widths. You use the spacers to set it up, depending on your frame, as described in the Shimano Dealer's Manual (DM): bike.shimano.com/en-EU/product/component/deorext-m8000/BB-MT800.html