Chain ring replacement-retro build

[Deleted member 41544]

I have just bought a 1991 diamond back ascent frame off e bay for £25 and I have a mid 90's deore lx 8 speed groupset that came on another trashed bike that I picked up for £35. So I'm going to build a bike combining these. Anyhow to to cut to the chase the chainrings are well past usable, but I'm struggling to find replacements that aren't very costly. I think they are 94pcd measuring.
Does anyone know where I can find some? Or should I just replace the whole chainset? Has anyone run a 1 X 8 setup as I think this could be a cost effective way.
Any help or input greatly received by a newbie retroist

 

[Daddy Pig]

I have been doing up my old 1996 mtb recently to get back out on the trails and I posed a similar question regarding 8 speed as I needed to change a few components, and was worried that I would need t also change the crankset. To be honest, it may be difficult to find replacement chainrings, and also it is likely that it is cheaper to upgrade to a new chainset anyway.

As for running 1x8 this is likely to be rather restrictive in terms of gearing, although it depends on your intentions. I'm not sure that you can get a large 8 speed cassette to make this any easier! If you need a cheap 8 speed front mech then you can pick one up for about £10 from Tredz.

 

[Deleted member 41544]

I have been doing up my old 1996 mtb recently to get back out on the trails and I posed a similar question regarding 8 speed as I needed to change a few components, and was worried that I would need t also change the crankset. To be honest, it may be difficult to find replacement chainrings, and also it is likely that it is cheaper to upgrade to a new chainset anyway.

As for running 1x8 this is likely to be rather restrictive in terms of gearing, although it depends on your intentions. I'm not sure that you can get a large 8 speed cassette to make this any easier! If you need a cheap 8 speed front mech then you can pick one up for about £10 from Tredz.

That's what I was thinking, it's gonna be around £60+ for chainrings then a bottom bracket. The 1 x 8 was to save buying three chainrings, probably better to be over geared than under geared aswell. Pleasure is my main priority so a new low end-ish chain set seems best bet

 

[fossyant]

Here is my Diamond Back Ascent. I did eventually fit a new chain set as it worked out cheaper in sales than just a ring.

 

[ChrisEyles]

Not sure about 94 bcd, most rings are 104/64 for MTB I think. SRAM do different sizes on some of their rings which may be worth checking. I've also got an old retro STX crankset with a weird bcd value, don't know what I'll do when those rings wear out!

Getting a whole crankset on ebay is a perfectly good option if you can't find replacement rings.

1x8 also works fine - on a new (well, old, but new to me) build I've just done I have a 32t ring up front (the middle ring from the old triple crankset) and an 11-30 8-speed cassette at the back. I'd prefer a 34t granny on the back but so far I've made it up all the climbs I usually tackly with a triple on my other MTB. It comes into its own at trail centres where you can mostly power up the climbs, but for longer rides on Dartmoor with a lot of long sloggy climbs I'd much rather have a triple up front.

 

[Deleted member 41544]

Here is my Diamond Back Ascent. I did eventually fit a new chain set as it worked out cheaper in sales than just a ring. View attachment 147470

Nice!! They look so much better than new bikes and they are much cheaper too, its cost me around frame, groupset, cables, bars, stem, seatpost, seat and wheels/tyres/tubes cost £80 so far, all decent stuff aswell with just chainrings and chain now to get. would be nuts to spend nearly as much again on those!

 

[Deleted member 41544]

Not sure about 94 bcd, most rings are 104/64 for MTB I think. SRAM do different sizes on some of their rings which may be worth checking. I've also got an old retro STX crankset with a weird bcd value, don't know what I'll do when those rings wear out!

Getting a whole crankset on ebay is a perfectly good option if you can't find replacement rings.

1x8 also works fine - on a new (well, old, but new to me) build I've just done I have a 32t ring up front (the middle ring from the old triple crankset) and an 11-30 8-speed cassette at the back. I'd prefer a 34t granny on the back but so far I've made it up all the climbs I usually tackly with a triple on my other MTB. It comes into its own at trail centres where you can mostly power up the climbs, but for longer rides on Dartmoor with a lot of long sloggy climbs I'd much rather have a triple up front.

I do a ride home from work its around 32 miles on the national cycle network, mostly towpaths and old railways that have been tarmacked, some actual off road sections, but one section on road is about a mile and half around 15% gradient and the only way to avoid such a climb would add about 15 miles on, so i'm thinking second hand chainset for now to keep cost down and get the build going then either upgrade later or replace rings as required

 

[Daddy Pig]

Have you got the necessary tool to remove the cranks? It could be almost impossible if not!

 

[Deleted member 41544]

Have you got the necessary tool to remove the cranks? It could be almost impossible if not!

Yeah I've got a little tool kit I bought off e bay and the frame is bare so new ones need installing which should be easy

 

[Jody]

Have you got the necessary tool to remove the cranks? It could be almost impossible if not!

A method I used when younger was wind the bolt back half a turn or so from tight and then ride round the block for 10 minutes. It should pop off the spline but not far enough to damage the spline. When it does push it back home before the bolt loosens further and you start to round the spline.

 

[ChrisEyles]

Yep, I've used that trick on a crank arm whose threads had been stripped. Worked fine with no ill effects.