Front & rear mech for 8 speed friction shifter

[niloc]

DAK if a new Tiagra front and Deore XT rear (10 speed) mech will work with an 8 speed cassette if I use friction shifters (no indexing)?

[peetee]

You may struggle to get an 8 speed chain through the gap between the jockey wheel side plates in some, if not all cog/chain wheel combinations.

[Brucey]

if the 8s chain scrawps on the RD side plates, longer screws and shim washers either side of the pulleys will fix it.

The FD is likely to be too narrow ; if so, with 8s chain the slightest deviation will cause scraping. I would suggest FD-R2000, because it is an 8s mech.

cheers

[Ross K]

For reference on the rear derailleur, I've been using an 8-speed chain for years with a 105 5700 (10 speed) rear mech on non-indexed friction levers with no issues. The front mech is an original Shimano 105 circa 1985!