Hi looking for advice on gearing, basically as I have a 48 tooth chainring and am looking for a winter training bike so would a
48/28t combo work with a 11/34 or 11/36 cassette.?

😕

or do I just buy a triple?

Is this on a road bike or cyclocross? A 28t is very small for either really, especially if you’ve got a great big cassette at the back. I’d suggest that anything more than 15 tooth jump between chainrings will be very hard for a front derailleur to cope with.

Hi sorry mountain bike but want something to link long road sections and then off road, good lord does that make it gravel cross?

48/36 should be fine with an 11/36 cassette, assuming you are running slicks?

I run a 48/36/26 with an 11/28 cassette on my MTB/hybrid with slicks and have never used the granny, I imagine 48/36 would be fine with a wider ratio cassette for all but the steepest climbs.

I use 40/28 chainrings on my 2×10 (11-36 cassette) and it works perfectly.

48/28 is a big jump… Don’t think you’ll get it to shift nicely but you might get it to crunchy shift horribly, which is actually fine if you’re not doing it too often. Or it might just entirely not work due to mech clearance. But for offroad you’ll be living in the granny ring which might be a bit low.

For summer I’d have said 32 front would be fine. But for winter with more mud etc honking along in a big gear is far less fun and sometimes just doesn’t work very well, difficult in mud and snow etc. I’m 1×10 on both my bikes just now with similiar gearing and I like it but I’ll be putting a granny back on something for winter.

Personally I’d not be using the 48 tbh. If I was going to go to Dublin, I wouldn’t start from here 😉