Cycling UK Forum

I need to replace a couple of chain rings on my trusty 1991 Marin Eldridge which I use for my daily commute of 10 miles. It still has the original shimano deore lx M530 front chain set 46-36-24, but the middle and outer rings are worn to the extent that I can't fit a new chain without it skipping badly. I have fitted a replacement cassette at the back, thinking that was where the skipping was happening, but it's still there, especially when applying power on the left crank with the new chain and cassette.

My question really is, can I buy replacement chainrings that will suit this chain set, compatible with the existing 7 speed setup or would it be better to replace the entire chain set?

the bcd is a standard one IIRC on all three rings, but 3 new rings is often about the same price as a new chainset.

Since you will go far to find better (stronger) cranks than the M530 ones, I'd suggest (if your cranks are in good shape) that you buy a cheap triple with the right size rings (e.g. from spa?) and put those rings on your cranks.

Sometimes chainrings go on sale and then you might pick up the ones you want for £5 each, but that can't be relied upon.

cheers

Bet it would be cheaper to buy a chainset.
Try Spa cycles for some nice and cheap ones or ebay for something even cheaper.
Chain ring can be 20 quid plus each.

£24 + p&p for two 110bcd chainrings in those sizes from Spa at present.

cheers

Thanks very much for all the helpful suggestions. I will try Spa for the chainrings as they seem reasonable and I would prefer to keep the existing chain set, if I can.

johnf wrote:I need to replace a couple of chain rings on my trusty 1991 Marin Eldridge which I use for my daily commute of 10 miles. It still has the original shimano deore lx M530 front chain set 46-36-24, but the middle and outer rings are worn.

My question really is, can I buy replacement chainrings that will suit this chain set, compatible with the existing 7 speed setup or would it be better to replace the entire chain set?

Not sure how useful this thought is, but if the bicycle is used for commuting and the smallest chain ring isn't used, have you ever thought about just having one chain ring at the front, of an intermediate size, like a 42 or a 38 tooth? You'd still have seven gears, but you'd have less to clean and lose the complexity of having a front mech/ front gear changer to adjust or worry about, and you'd only have one chain ring to wear out, making the bike cheaper to run. As the chain wouldn't been expected to move from one chain ring to another it means that you could possibly have a stainless steel chainring which wouldn't wear out so quickly (although this is reflected in the price) or even an elipitical chain ring, as mentioned elsewhere in this forum. Admittedly you'd lose the extremes of the your current gear range, and there would be a very slight risk that you'd may have to mount some sort of chain keeper device if (and its a big if) the chain ever fell off the chain ring....anyway, just thought i'd mention it

Actually.. another thought crosses my mind... does the worn out chain rings had any 'gear shifting ramps' or gear shifting aid pins or anything like that? If the answer is 'no' have you considered just unbolting your existing worn chain rings and then mounting them the other way around (so that the worn sides of the chain ring teeth aren't being presented to the chain as you peddle)? That may help..

..of course going back to my previous idea, if you only had one chain ring on the front, then once that was worn, you can just flip it over and use the other side..

..but whether you have one chain ring or lots, what i would say is to get maximum wear out of them, every thousand miles consider unbolting them, and then rebolting them one hole forward (unless the chain ring has a pin to stop the chain falling between the crank arm and chain, should the chain come off). Y'see most of the chain ring wear is at 90 degrees to the pedal crank. So by moving the chain ring forward after one thousand miles you reduce the amount of wear in that area (by presenting fresh teeth to it). Gosh hope all this makes sense

As you were, gentlemen, as you were..

cycle tramp wrote:
As the chain wouldn't been expected to move from one chain ring to another it means that you could possibly have a stainless steel chainring which wouldn't wear out so quickly (

A question from the technically a bit limited cycletramp. Why does the lack of a need for shifting open up the possibility of a steel ring?

thanks again for the stem.

generally speaking what sort of tolerances in 'straightness' / 'flatness' do people find with chainrings? every summer when the lightweight bike comes out to play (i say 'every' but...) i remember that the campagnolo 53T ring it runs has a drift of 2-3 mm to the right as it revolves. is this commonplace?

New stupid question from me (in addition to one above about steel) - trust the OP doesn't mind me asking in this thread - it's kinda relevant.

Are chainrings speed-specific and if so what specs do I look for?

Like the OP I may need a new chainring for 7 speed - it's a single chainring set-up paired to an SRAM 3-speed Dualdrive for 21 speeds on the Dahon Speed Pro.

mig wrote:generally speaking what sort of tolerances in 'straightness' / 'flatness' do people find with chainrings? every summer when the lightweight bike comes out to play (i say 'every' but...) i remember that the campagnolo 53T ring it runs has a drift of 2-3 mm to the right as it revolves. is this commonplace?

Have you fitted a modern Campag chainring designed with one leg to bolt into the back of the crank? The 5 arms are not the same thickness on these rings. I've had a customer do this.

thanks for the tip but not in this case no. this chainset came complete and is from a more recent time. it just seems warped to me!

Portland wrote:

cycle tramp wrote:
As the chain wouldn't been expected to move from one chain ring to another it means that you could possibly have a stainless steel chainring which wouldn't wear out so quickly (

A question from the technically a bit limited cycletramp. Why does the lack of a need for shifting open up the possibility of a steel ring?

thanks again for the stem.

Oops, apologies, rather a failure of communication on my part. There are stainless steel chain rings for those who multiple chain rings on their chain set, however, these chain rings tend to exist for the inner ring (between 22 and 28 teeth) where the small disadvantage of the weight of the chain ring (as steel is heavier than alloy) is outweighted by the fact that this very small chain ring will last longer than its alloy counterpart.

However any quality aftermarket chain ring with more than 28 teeth are usually made of some sort of alloy and will have features like shortened teeth, ramps and pins to help the chain change from one chain ring to the next. The only quality stainless steel chain rings larger than 28 teeth (that i have found so far) are those from surly ( http://surlybikes.com/parts/drivetrain ), and whilst they are lovely things (over 1000 miles of wear and no damage to the teeth so far) the chain rings produced by surly don't have any features (such as ramps, shortened teeth or pins) to help the chain move from one chain ring to the next... so whilst it may be possible to use multiple chain rings from surly on your chain set, shifting the chain from one chain ring to the next will not be as precise, and will be slower. Hence surly themselves will only recommend their use for those drive train set ups that only use one chain ring (such as IHG, fixed wheels, timing chains on tandems & so on).

Is there a market for stainless steel chain rings with ramps and short teeth and pins, which can be used in multiple chain ring chain sets... for those who don't mind a bit of weight? Possibly...although for the moment, you may be better off designing your own and then finding someone with a lazer cutter (although that's a completely different thread)

Hope this helps (although i've got a sinking feeling i've just made matters more confusing)

Portland wrote:New stupid question from me (in addition to one above about steel) - trust the OP doesn't mind me asking in this thread - it's kinda relevant.

Are chainrings speed-specific and if so what specs do I look for?

Like the OP I may need a new chainring for 7 speed - it's a single chainring set-up paired to an SRAM 3-speed Dualdrive for 21 speeds on the Dahon Speed Pro.

No such thing as a stupid question! And since the advent of 10 speeds, i'm no longer sure of the answer! However, the most important thing is the BCD of your chainset (that's the bolt circle diameter). Providing your new chain ring has the same bolt circle diameter of your old chain ring and the chain you are using is wide enough to allow the teeth of your new chain ring to poke through, then that's all what matters...

if you take the bike along to your bike shop they should be able to tell you what the BCD is, of your existing chain ring, which will make ordering a new one easier.

..as a follow on about BCD's i thought i'd add this link http://www.porkchopbmx.com/5-Bolt-110-1 ... s_c108.htm (which if it doesn't work features a number of chain rings in bright fashionable colours, and each chain ring is drilled for both 110 & 130 bcd's ~ making them ideal for anyone who has more than one bike with different BCD's. Admittedly is probably a fashion thing, but from the point of view of a shop keeper, who can't carry too much stock, then perhaps having chain rings with mulitple BCDs could be the way forward).. okay, i'll shut up now