Cassette is skipping; need a new one. The T-rex will be OK, gets used very rarely so won’t be worn like the cassette is. However, I recall the T-rex is specific to either Shimano or Sram, and I can’t remember what version I’ve got or hence what cassette.

Is there a way to tell without dismantling the cassette and taking off? I know that’s lazy but if I take it apart I’ll have to clean it all down, and it’s not skipping badly enough in all gears yet that i can’t leave it on until I get a new one delivered (next weekend) so I can ride tomorrow and Monday.

Or should I just get a Sunrace and be done – what’s a second hand T-rex 40T worth?

I’m confused. Shirley you just look at what rear mech you have and that’ll tell you?

Mech won’t tell me anything, you can use shimano on sram cassettes and vice versa.

I love my sunrace on my titus

sorry Ill go back to drinking beer.

I had a T-Rex and my son has a Sunrace cassette. Both work well. Sunrise was easier to set up (no messing with a 16T sprocket).

Are you saying that your current setup is so dirty that you can’t tell if it’s currently a sram or shimano cassette with a strip and clean? If so, I think I might know why it’s not shifting well

I’m sure mine had “shimano only” printed on it

No, it’s perfectly functionally clean, but I’m a bit OCD and if I take it off to look at it I’ll end up with it in a bucket and lose an hour I really can’t be arsed to spend now.

So, is there anyway to tell.

Oh and read the OP. It shifts fine, it skips (because I have a new chain on which I thought I’d get away with but clearly I’m not)

And meanwhile you have waited an hour for a solution/answer on here .

I’m not meaning to take this piss (just gently rib you perhaps). What cassette is in right now? Wouldn’t that tell you which t-rex you’ve matched it to?

I haven’t been sat here waiting, I’m watching football as well.

Onza; yes, that would be true but I can’t find any identifying mark on the cassette either. It’ll probably be printed on the back, meaning if I take it apart I can find out……. and then, etc.

And you could have watched football with the cassette in a bucket.

The lock ring would be a good place to look.

should I have taken the bucket and the cassette to the game with me??

It’s not the obvious accompaniment.

Amazing things these mobile devices…..

😳 found out.

The lockring is a tarty after market colour matched one

So, we’re all invested now, you have to tell us, which is it?

So its sitting on a bike at home and you still dont have your answer.

It could have been sitting in a bucket at home and you would have your answer when you got back.

Numpty. sorry that was out of order. But someones grumpy. Sunderland fan perhaps.

I’ll take it apart when I get home…… sighs.

Hoped to be able to order a new cassette on line rather than watch the half time entertainment, instead ebds up being roundly abused 😉

Nice nairnster.

One day maybe you’ll ask a simple question hoping for an answer. I hope someone helps you out.

I would have just checked the cassette tbh.

And you were being one.

I’d just order the sun race now. Mine shifts much better than my old expander setup. I also have an 11spd XT mech instead of a 10spd as it’s designed for wide range cassettes and has the same pull ratio.

But someones grumpy. Sunderland fan perhaps.

nothing as glamorous as that, just local league stuff.

Not sure what sort of a one I was being, asked a simple question, which turns out even simpler now I know the answer, and got a mix of unhelpful advice and abuse (which I see you have now retracted). Sorry if you think that makes me a prick.

The answer is ……. Sram

There’s nothing (visible) on the cassette to ID it that I can find, however on the T-Rex, etched into the cog, under only one of the (four) logos there is a tiny SR. Which I’m guessing means Sram, and Shimano will have a S or SH instead. And which I missed while looking quickly before heading out and isn’t visible on the photo I took of it.

Phew, another mystery solved.

right, comparing the prices of Sram cassettes vs a new Sunrace, I’m going Sunrace.

Anyone want a T-Rex 40T extender for a Sram cassette – will throw in a worn 16t single cog to close the gap as well.

I’m running both. On one bike I’ve got a Shimano 12-36 with a 40t Hope and a 16t cog to replace the 15t, on the other I’ve got a Sunrace 12-40. The Sunrace is cheaper and shifts as well, if not better than the buggered about with Shimano.