Mrs B's road bike has an ultegra HT2 screw fit BB. Bike washing this morning and i discivered it has a ton of play. I dont have an Ultegra one to swap, but i do have an XT. Are they the same with just a different size (length) inner tube?
Thanks
Ian

Shoet answer... No

Thanks Shaf!

Obviously not what i wanted to hear...but thank you

Ian

BreninBeener wrote: ↑Sat Oct 31, 2020 1:03 pm Thanks Shaf!

Obviously not what i wanted to hear...but thank you

Ian

It can work.
Road hollowtech 2 BBs are an overall width of 90mm. Each cup is 11mm
MTB hollowtech 2 BBs are an overall width of 95.5mm. Each cup is 10mm. The difference is made up with the 3 x 2.5mm spacers (68 shell).

So you can use an MTB BB, without the spacers. You may need to fit a single spacer under the DS cup, you may not. Obvs will need to use the internal plastic shield from the Road BB.

I stand corrected. I usually just trust Shimano in that dept where it says mtb I use for mtb sounds faffy and BB can be had for about £15 if you shopped around

I only know 'cos had same question recently so fresh in mind. The beauty of Shimano H2 chainsets is a small degree of flexibility on crank width on the spline unlike SRAM / Raceface which bottom out and rely on additional washers. Guess thats why H2 hasn't changed in 17 years (I have gone and done it now havent I )

(and still have Sq taper on 2 bikes )

wriggles wrote: ↑Sat Oct 31, 2020 1:25 pm I only know 'cos had same question recently so fresh in mind. The beauty of Shimano H2 chainsets is a small degree of flexibility on crank width on the spline unlike SRAM / Raceface which bottom out and rely on additional washers. Guess thats why H2 hasn't changed in 17 years (I have gone and done it now havent I )

(and still have Sq taper on 2 bikes )

You still have square taper wow...

redefined_cycles wrote: ↑Sat Oct 31, 2020 1:27 pm

wriggles wrote: ↑Sat Oct 31, 2020 1:25 pm I only know 'cos had same question recently so fresh in mind. The beauty of Shimano H2 chainsets is a small degree of flexibility on crank width on the spline unlike SRAM / Raceface which bottom out and rely on additional washers. Guess thats why H2 hasn't changed in 17 years (I have gone and done it now havent I )

(and still have Sq taper on 2 bikes )

You still have square taper wow...

Cotter pins on 3 of my bikes! (but one is being upgraded to square taper)

Square taper BB on both my main bikes.
Royce BB’s with Middleburn 5 arm ATB pattern spiders. If it ain’t broke don’t fix it.
It’s a world more reliable than the Campag Powertorque setup on my road bike which needs a new BB every year and £130 of tools to change it.

I've used a mtb BB on a road bike. Left the plastic tube out, it's not essential. I've a toolbox full of different spacers so can usually bodge things.

a gravel bike had has an XT bottom bracket (and all three plastic spacers used)
another gravel bike has road bottom braket (ultegra, BBR60)

Yeah I have a Deore BB on my gravel bike (it is in use with an mtb chainset though so possibly a moot point). Incidentally Berocca tubes can be cut up and adapted to extend the axle tube on Shimano BBs, that's what I've done multiple times when using them on my fat bike (100mm BB width).

Thanks for all your help.

We have ordered an Ultegra BB that should arrive today

Regards

Ian

I swapped an mtb BB from my Arkose for an Ultegra one. Bit of a head scratcher that one until I twigged they were different. The next hassle if I remember correctly is that the MTB BB tool doesn't fit a road one. I recall wishing I'd just replaced like with like.

They are interchangeable, but you need to use spacers for MTB, no spacers for road and change the inner plastic shield or run without the shield.

I used to use Dura Ace HT2 BB on the MTB as they were a bit lighter and worked just fine.

Jurassic wrote: ↑Sun Nov 01, 2020 7:20 pm Incidentally Berocca tubes can be cut up and adapted to extend the axle tube on Shimano BBs,

This is the sort of knowledge I come on here to gain.

Incidentally Berocca tubes can be cut up and adapted to extend the axle tube

Bodging, but on a really good day! ®

Landslide wrote: ↑Wed Nov 04, 2020 10:22 am

Incidentally Berocca tubes can be cut up and adapted to extend the axle tube

Bodging, but on a really good day! ®

Cut the Shimano axle tube in the middle and one end of the Berocca tube will pop right on. Cut of the closed end of the Berocca tube to the required length and apply a little heat and slide it onto the other cut end of the Shimano axle tube. Job done.