Shimano Di* do and do not.

[Graham]

B screw had about 1/2 turn from the 28 that was fitted. Shifting is as good. Chain length is critical imho and i used an Ultegra cassette and new Ultegra chain. My LBS had the bike in for a service and checked out the rear mech and shifting and all was fine. I am not the only one in these parts parts running the 30T as we have some silly hills round here.

WORD OF WARNING.

The most critical thing is the length of the hanger!!!!!, if it is short it wont work and you may wrech the rear mech.

Looking at the techdoc, the 7970 (10 speed that I have) only comes in SS so maybe the 30 won't work from what you're saying?

My intention is to run Ultegra cassettes with 10 speed Ultegra chains, unless I can get hold of cheap dura ace chains. Dura ace cassettes are about £100 more than Ultegra.

 

[Peteaud]

Looking at the techdoc, the 7970 (10 speed that I have) only comes in SS so maybe the 30 won't work from what you're saying?

My intention is to run Ultegra cassettes with 10 speed Ultegra chains, unless I can get hold of cheap dura ace chains. Dura ace cassettes are about £100 more than Ultegra.

Shimano tech docs are not worth the paper they are written on, to a point.

My tiagra has been running a 30T for years, shimano say 28T max.

My DI2 28max has 30T

It might work, it might not.

 

[Graham]

Shimano tech docs are not worth the paper they are written on, to a point.

My tiagra has been running a 30T for years, shimano say 28T max.

My DI2 28max has 30T

It might work, it might not.

Suppose so. I've got 30T on my 2008 tiagra and never gave it a moments thought! I guess shelling out for dura ace makes you think a bit harder!

Screw it, I will give it a whirl with the bike on the stand and see how it copes.

 

[Peteaud]

Suppose so. I've got 30T on my 2008 tiagra and never gave it a moments thought! I guess shelling out for dura ace makes you think a bit harder!

Screw it, I will give it a whirl with the bike on the stand and see how it copes.

If it has 28 at the moment and runs with plenty of give left on the rear mech, a 30T wont be that much different as the outside diameter is not much more. When i did mine i used an Ultegra cassette and new chain and had it on a stand and rotated the cranks very very carefully.

2008 Tiagra says 28T Max so yours is doing what Shimano says it wont!!!

 

[Mr Haematocrit]

I know someone with a Di2 MTB conversion running a 36 without to much issue by running a longer gear mech plate.
I tried to upgrade the servo's for them and it started to thow the chain more regularly.

 

[chunkymonkey909]

Sorry if this has already been asked.
I have Ultegra Di2 and mechanical disc brakes on a road bike. What I would like to do is upgrade the mechanical discs to the new di2 hydraulic discs.
From what I have read I can upgrade the di2 STI levers to the hydraulic STI's and calipers but apparently the new STI's only have 1 port rather than 2 ports like I currently have. This is a problem as I have the climbing switch connected to one of them. Can I buy a 5 port junction box to make the new setup work or is that only compatible with Dura Ace di2?
Thanks

Martin

 

[Sterba]

Please tell me why you think the hydraulic discs will be better than the mechanical ones. I am particularly interested if part of the reason is that they take less effort to achive the same stopping force.

 

[chunkymonkey909]

For me there are two attractions to hydraulic brakes - there is no steel cable which is prone to corrosion (especially as this is for my winter bike) and they also have a much lighter feel due to less friction ie no cable.

 

[BikeLiker]

Not sure how widely known this is, I couldn't find any technical reference, but Ui2 can be upgraded & managed without the SM PC E1 interface if you have the BCR2 internal battery charger. More details here.
Using this system I have upgraded all my firmware and programmed multi-shifting so it seems to have all the functionality of the stand alone interface.

 

[albion]

...My LBS had the bike in for a service and checked out the rear mech and shifting and all was fine. I am not the only one in these parts parts running the 30T as we have some silly hills round here.
WORD OF WARNING.

The most critical thing is the length of the hanger!!!!!, if it is short it wont work and you may wrech the rear mech.

I was giving my old steel bike a run today and a cyclist was carrying his bike into Wynyard County Park to phone a taxi.
His Di2 rear mech had crumpled.
I have no idea is it is the 30 scenario but thinking about it, it looked so when I offered to help, in vain.

 

[Peteaud]

I was giving my old steel bike a run today and a cyclist was carrying his bike into Wynyard County Park to phone a taxi.
His Di2 rear mech had crumpled.
I have no idea is it is the 30 scenario but thinking about it, it looked so when I offered to help, in vain.

Could be many things, ive run my 30 with no issues, the 28 standard and 30 diameters are not massively different.

 

[albion]

It was mangled and twisted at the lowest big cog rear gear but yes, many a reason.

 

[azatlas]

Planning to travel from Northern England to the Pyrenees in the summer to see the tour. My bike will be on my car roof bars....will the Di2 be ok !?....Any recommendations other than putting the kids up there and the bike in the car!

 

[Mr Haematocrit]

Won't be a problem from my experience. All I do for added security is I put the Di2 into shock protection mode.

 

[azatlas]

Hi thanks for the advice....I better read the manual...never even heard of 'shock protection Mode'...