Drive train renewal

[Benjahmin]

Judging by the daylight I can see between chain and sprocket and the 'chattering' noise in most gears, then I think it's time for a sprocket/chain change. The bike has done around 6000 miles in hilly west Wales and has had one new chain. The bike originally had 8x3 gearing but I removed the granny ring to fit the pas disc.
Thing is I really like the gearing as it is and don't want to alter anything - even the cranks.
The cassette is no problem (Shimano HG200-8) found several places to buy.
But I'm having trouble finding the front rings. What I have now are Truvativ 48, 38, on 104 bcd. When I do see them I'm not sure they're correct. The 48t ring has fittings for a chain guard ring. I assume the middle ring fits to the same 104bcd fitting. What I can't tell is if the 38t rings I'm seeing have the granny ring locators in them (I drilled my pas disc and bolted to two of the granny ring fitments).
Can anyone point me to what I need to search for? Just want to buy the rings (3 if I have to), keep the cranks.
Much appreciated.

 

[anotherkiwi]

If the 38 is listed as being for a triple it will have the holes. Other 38s will be the external ring of a 2x setup.

 

[Benjahmin]

Thanks AK. Kinda thought that would be the case.

 

[Benjahmin]

Well this is bonkers. After a second scan through the interweb thingy, it seems that it is going to be WAY cheaper to buy a complete crankset rather than just rings (not that I can find the centre ring). I hate waste and really didn't want to throw away a perfectly good pair of crank arms.
There is also the issue of crank length. Is this measured from centre of rotation to centre of pedal hole? If I can get the same crank length, I'll just hope that the crank offset is the same.

 

[Audio2]

Buy the new chain set & use the new rings on your old chain set.

 

[sjpt]

Still a waste of crank arms; irritating. I've got a few arms hanging around. If you do get the complete set make sure it is the same quality as the individual rings would have been. Did you check Spa cycles, they usually have a wide range of rings.

 

[Benjahmin]

I did yeh. May give them, and SJS a ring after the new year.
May need a bottom bracket too, this one doesn't rotate very freely, I'm assuming it should.

 

[Benjahmin]

So finally got around to it. After spending many hours finding the right crank set, it proved not to be !
I tried to get a 48-38-28, 104 bcd with all rings bolted together. Turns out the one I got (Suntour) the granny ring is riveted in place. This was awkward because I had removed the previous one to bolt the pas disc in place. Anyway the rivets have a sort of hollow centre which took a 5mm drill without damaging th e rivet. So drilled through, marked the pas disc and drilled that with a 3mm. Used a stailess steel wood screw to bite into the plastic and ground the end of flat to the disc.
I know - bodgerama, but hey it works. Aren't they the best?
So now I'm back to the origional 24 gears, useful around here.
Instead of a 12-32 I got an 11-32 'cos that's what was available. Surprisingly that loss of one tooth seems to have made a 4-6mph difference to spin out speed.
Indexing took an age but all is now smooth and quiet.
When I took the old chain of it did a full 90* sideways - got my monies worth out of that one I think.

As always thanks for the help guys.