Can I mix these SRAM Apex components with Shimano/Ofmega components on my bike temporarily?

Question

I own a Fausto Coppi vintage bike. Currently I have RSX shifters with Shimano exage 300EX front and rear derailleurs.

I am switching my whole setup to accomodate 10 speed. My new wheels fit well. I have just ordered a SRAM Apex mini set. This comes with a 10 speed chain, shifters, cassette, rear derailleur and brakes. I do want to eventually switch out the bottom bracket and crankset but I currently have an Ofmega 52/42 crankset. I also want to switch out the front derailleur as well.

I just want to know if this setup will not work or cause damage to components until I can replace the front derailleur, BB and crankset to match the Sram Apex set?

So to be clear this will be SRAM Apex rear derailleur, shifters, cassette and chain. But the mixed components will be shimano Exage 300ex front derailleur and Ofmega 52/42 crankset. This is strictly temporary but I just want to know if it'll work okay. Thanks

Answer 1

The 10 speed chain is narrower than the chain your crankset was originally designed for. With narrower chain there is the risk that the chain slips between chainrings and is stuck there. This is not a fun situation, but if you shift very carefully (i.e. make sure to shift all the way quickly) and check that shift was successful before applying power, you might get away with it.

As already mentioned in other answer, front derailleur cable pull is also an issue. If you keep the original downtube shifter, you can work around cage width issue by overshifting and letting the shifter back after chain has shifted.

Answer 2

I think your proposal sounds good, you already have most of the parts you need.

Regarding the chainset, Chris Bell on his website suggests that up to 10-speed there is no real difference in ring spacing or if there is it should be minimal.

There is often confusion about so-called '10 speed chainrings' and '11 speed chainrings'- but there are no such things as all derailleur chainrings are suitable for all systems from 3 to 11 speed. However some '10 speed' and '11 speed' cranks place their chainrings slightly closer together, but this isn't usually critical. https://www.cornant.uk/info/cranks.html

Therefore you should be fine using the Ofmega even though it might not give you the very best shifts. There are some effects that can occur shifting up to the big ring with the narrower chain on rings that don't have the helper pins and ramps, but you can mitigate these by shifting carefully.

I would suggest you use a 10-speed front derailleur. Any of 10-speed SRAM, Campagnolo 10s (eg Veloce), older Shimano 10s (6700, 5700, 4600) will be compatible with the SRAM shifter. The width of the cage does make a difference. The Exage front mech will be OK in terms of cable pull but may struggle at some chain angles as it is designed for a wider chain.

Answer 3

Proof's in the pudding, but generally you should be fine with this setup as long as the frame's OLD is large enough to take your new rear wheel hub.

The trick is to keep the front mech and shifter compatible with each other, and keep the rear mech and shifter and cassette compatible.

One interaction can be that the narrower width of the 10 speed chain takes longer to move chainrings at the front because the front mech's cage is for a wider chain. For a beater bike you might squash the cage horizontally a bit, or learn to live with it.

Also the RSX shifter on the left of your bars will be mostly grey, and the new one on the right will be much more modern-looking. A workaround here is to use a downtube shifter on the left for the front mech, and leave the left brifter as only a brake. This was a thing in the 90s, noticeably some yellow texan.

Answer 4

The pull-rate (cable per click) on SRAM is very different from Shimano. With downtube shifters you could switch to friction mode and use any rear mech.

Shimano STI brake lever shifters will not work with SRAM. There are also many variants within Shimano's ranges over the years that have strange compatibility issues - some useful, others not.

If you are careful you can experiment but make sure you do your endstops BEFORE anything else.

Don't forget hanger alignment and B-Screw as well.

Good Luck