Rear wheel cassettes

[Fordulike]

If I had two complete rear wheels, one with a 7 speed SRAM cassette fitted, and the other a Shimano 7 speed cassette.

Would I be able to use either one with a 7 speed derailleur from either manufacturer?

I'm not fussed if the actual cassettes can be interchanged, but whether the different manufacturer's gear cogs cause any problems with each others derailleurs.

 

[Deleted member 4366]

I swapped an 8 speed cassette wheel for a 7 speed freewheel without any problems, but I changed the gearchanger at the same time because of the different number of gears. I had to re-set the endstops and adjust the cable because the cogs weren't in exactly the same position. Once adjusted, the gearchange works perfectly. In your case, because you have the same number of gears, it should be a straight swap and re-adjustment of the end-stops and cable.

 

[Fordulike]

I swapped an 8 speed cassette wheel for a 7 speed freewheel without any problems, but I changed the gearchanger at the same time because of the different number of gears. I had to re-set the endstops and adjust the cable because the cogs weren't in exactly the same position. Once adjusted, the gearchange works perfectly. In your case, because you have the same number of gears, it should be a straight swap and re-adjustment of the end-stops and cable.

Thanks d8veh. It's good to know that compatibility between the two manufacturers isn't a problem.

 

[Andrew harvey]

The cassettes and freewheels are interchangeable on 7 and 8 speeds, but the gear selectors and derailiers aren't, they have a different amount of pull on the cable.

 

[Scottyf]

I have shimano gear changers and derailers but changed to a higher speed sun race cassette and just re-adjusted the cables. Everything works fine.

Its just I need a different set of tools to actually take the cassette off again.
But there that cheap usually its not worth worrying about. I just take the wheel down the LBS and ask them to take it off and buy a complete new one.

 

[flecc]

SRAM make a range of Shimano compatible twistgrip changers that work with both, the twist tolerances cope well with the pull variations that Andrew mentions. I've used these on two Shimano equipped bikes, including one with a megarange set.

 

[electric_avenue]

I had to re-set the endstops and adjust the cable because the cogs weren't in exactly the same position. Once adjusted, the gearchange works perfectly.

Wonderful you can throw that in like its the easiest thing to do. I've never managed to satisfactorily adjust a shimino....come to that I've used bike shops that mess it up as well. You know of a definitive guide?

 

[flecc]

Pending d8veh replying, I think the simplicity of the Shimano technical docs instructions are a good guide, here's one example, the last but one column applies for the rear mechanism:

Shimano technical document

and for a more comprehensive guide:

Sheldon Brown on derailleur adjustment
.

 

[Deleted member 4366]

Wonderful you can throw that in like its the easiest thing to do. I've never managed to satisfactorily adjust a shimino....come to that I've used bike shops that mess it up as well. You know of a definitive guide?

It's not difficult as long as you can get your head round how it works. The two stop adjuster screws are physical stops that prevent the derailleur from going too far, i.e. lower than first gear or higher than top gear. The cable just pulls the derailleur from side to side, so my method is:
1 Loosen the cable
2 set the high gear end stop by turning the pedals and watching where the chain tries to go. Adjust until the chain is central to top gear.
3 screw the cable adjuster at then end of the cable outer right in
4 pull the cable tight and fix it there with the cable clamp screw
5 check that that you can get all the gears with the gear-changer. If you can, then set the first gear end stop. Normally you can't. Then you need the next steps:
6 if it won't quite go into bottom, use the cable adjuster
7 if bottom gear or more aren't reach, put it back in top gear to let the cable loose unscrew the clamp screw and pull it a bit tighter
8 Repeat steps 6 and 7 until you can get all the gears
9 If it grinds in any position, use the cable end adjuster to pull it a bit more or less.
10 set the first gear end stop

It's an interitave process and normally takes two or three goes before the cable is in the right position. The rest is easy, but you have to use your eyes to see where the chain is trying to position itself to know whether to loosen or tighten the cable position. I'm sure all the experts will tell me that this method is wrong, but it works for me.

 

[electric_avenue]

@Flecc. Well, that sheldon brown description is the reason I've always struggled. If its that complicated the whole thing needs a complete re-design. I printed the shimano doc though, lets see if that learns me sommat.

@d8veh. Thanks for taking the time to write that up. I've saved it and I'll try it out next time I have a clicky chain or something - which seems to happen a lot.