Why wont my gears work/ rear derailleur

[Solecyclist]

Hi Folks can any one tell me if a shimano Deore 11 speed rear deraileur is compatible with Shimano 105 5800?.Ive had such a deraileur fitted to my 105 system as my local bikeshop didnt have the 105 rear deraileur in stock.Im having so much trouble getting onto my 32 tooth sprocket and its imposdible to get to my 11 tooth sprocket.Any help would be so appreciated.Thankyou!

 

[Cycleops]

Have they adjusted the Hi-Lo set screws correctly? You say your LBS fitted it? Take it back. Sounds like the most likely cause. Deore 5100 handles 32 & 11t.

 

[Ajax Bay]

check . . . . the hanger alignment..

I guess I think the symptoms described by the OP (not able to shift the full width of the cassette: both ends) does not point to a hanger out of vertical.

 

[Ajax Bay]

Hi Folks can any one tell me if a shimano Deore 11 speed rear deraileur is compatible with Shimano 105 5800?.Ive had such a deraileur fitted to my 105 system as my local bikeshop didnt have the 105 rear deraileur in stock.Im having so much trouble getting onto my 32 tooth sprocket and its imposdible to get to my 11 tooth sprocket.Any help would be so appreciated.Thankyou!

I shall have a go and shall assume that the RD is an M-5100 (Deore). I have not tested this.
The shift ratio of the Deore RD (11sp) is 1.1. A Road RD has a shift ratio of 1.4 - and 'obviously' the 105 ST-5800s at each click will pull the required cable. (All Shimano 11sp cassettes have a sprocket pitch of 3.74mm.)

So the OP's new RD is moving its cage only 80% of the distance needed (per sprocket)
Getting the cage right in the middle sprocket (which is maybe what the bike shop has done) would mean that the RD will not 'reach' across to the smallest (11) and largest (1) sprocket.
Which is the symptom described in the OP. Unscrewing the limit screws will have no effect.
*'Shift ratio' is the distance in mm) that RD moves laterally per 1 mm of cable movement.

 

[Jenkins]

You'll probably find that the Deore 11 speed MTB equipment cannot be used with 105 road shifters
https://bicycles.stackexchange.com/...eur-compatible-with-shimano-105-11-speed-grou

 

[Smokin Joe]

Hi Folks can any one tell me if a shimano Deore 11 speed rear deraileur is compatible with Shimano 105 5800?.Ive had such a deraileur fitted to my 105 system as my local bikeshop didnt have the 105 rear deraileur in stock.Im having so much trouble getting onto my 32 tooth sprocket and its imposdible to get to my 11 tooth sprocket.Any help would be so appreciated.Thankyou!

The "Mechanic" (Saturday boy?) who fitted it is a prat.