Support road.cc

Like this site? Help us to make it better.

forum
road.cc bike forum

Using a 11/30t cassette with a ultegra 6870 Di2 short cage rear derailleur?

by Worthatri
Sat, Jul 29, 2017 17:22
8

 

I've tried finding this out but can't seem to get an answer, so hopefully, somebody here can help?

I'm upgrading to ultegra 6870 Di2 and as part of the upgrade, I bought a new ultegra 8000 series Shimano  11/30t cassette.

If used with the new ultegra 8000 series, I think I’m correct in saying you can now use the short cage rear derailleur?

However, the groupset I have bought has the 6870 Di2 short cage rear derailleur, so my question is - can I still use an 11/30t ultegra 8000 series cassette with the short cage 6870 Di2 rear derailleur, or do you need the medium cage rear derailleur if riding the 6870 ultegra series?

I’ve spoken to Wiggle and Evans and have been given conflicting advice.

Wiggle say it will be fine, Evans said you’ll need a medium cage. I’ve tried looking it up on the shimano site, but can find anything to confirm it one way or the other.

6870 is 11/28t for short cage and 11/32t for medium, no mention of 11/30t as it wasn’t in the 6870 range (is there a reason for this? Seems odd that I was missed out of the range initially?)

8000 is 11/30t short cage and 11/32t for medium.

I’m hoping the short cage will be alright as I've already bought the groupset!

Any advice gratefully received.

 

Thanks

 

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

Add new comment

8 comments

Avatar
CXR94Di2 | 6 years ago
0 likes

Bridge of sighs

Avatar
ianSWBB | 6 years ago
0 likes

We often come across this problem in the workshop - when customers want to run larger cassettes with the smaller cage derailleurs

 

One easy solution is to use the Wolf Tooth Components Road Link

https://www.wolftoothcomponents.com/products/roadlink

yes

Avatar
Charlie-CarbsAn... | 6 years ago
0 likes

You can run a 32 , so 30 will be fine, on all short cage rear derailleurs both 10 speed and 11 speed. It works perfectly, so you only need to change chain length if you want to run big big (cross chained). Wind the B screw in a bit and it will shift great. Look on youtube for tutuorials.

Also on  a long cage shimano derialleur you should be able to fit up to a 36t on the rear.

Avatar
Worthatri | 6 years ago
0 likes

 

Thanks very much, glad the consensus is it will be ok.

The set up at the minute is 52/36 11/32 with a long cage, but for the Di2 upgrade I bought 52/36 11-30t with a short cage as I had read in the blurb on the new ultegra 8000, that 11-30t was ok with the short cage.

Worry was I don't have the 8000 series Di2 rear derailleur, but rather the 6870, but it sounds like this won't matter.

Thanks again for the advice

 

 

Avatar
VeloUSA | 6 years ago
0 likes

I concur with b-screw adjustment for a short cage on 11-32 cassette.Tighten the b-screw in a bit to get it to not make noise on the 32T cog. You will find it shifts as smoothly and as quickly as it did with an 11-28 cassette except it is a bit slower between the two smallest cogs; that’s to be expected with the b-screw pulling the upper jockey wheel further away from those small cogs.

Avatar
joeegg | 6 years ago
0 likes

A friend is running a 32 with a short cage Di2. No problems.

Avatar
CXR94Di2 | 6 years ago
0 likes

What size Cass is on now ? If 11-28 I would say yes it will fit and slightly adjust B screw. It quick test is put the gears on big big and adjust the B screw and see how much further the rear derailleur moved back. If you get like 5mm or then it will fit no problems.

Avatar
BehindTheBikesheds | 6 years ago
0 likes

6800 SS, no problem with 30, in fact some can do the 32t with the SS.

If the design is the same then can't see why not, just screw in the B screw all the way, possibly even reverse it.

Latest Comments