Token chainrings from T7

xxamr_corpxx

I'm quite interested in this one : Anyone used them? I'm planning to replace the 39 tooth on my roadie with this to get some lower gearing, in effect make a cheap compact crank.

http://www.torpedo7.com/page/bikes/...in_bike/MCHR440

__________________
2004 Trek 1000
2005 Giant Elwood
ACE Folding Bicycle

thomas_cho

The 34 tooth chainring is a 110bcd, your 39 one is a 130 bcd. They are not interchangeble. You would have to replace your crankset with a compact one to get that gearing.

cluster blaster

As Thomas (above) said, that'll depend on your cranks. If you have 110 BCD cranks and currently use 39T chain ring, then go ahead. If you have 130 BCD cranks then you'll have to change the crank first.

Vast majority of roadies will be equipped with 130 BCD cranks. Those with 110 will be either 15+ year old (old steel bikes used to have them!) or if new, they'll have the chain ring already as 36T or 34T....

If not sure, take your bike to a bike shop and ask them what BCD your crank is.

If you want to know more, there's a lot of info on www.sheldonbrown.com.

xxamr_corpxx

Yes yes, I've measured the BCD to be 110mm. I was actually wondering if this particular brand is any good.

__________________
2004 Trek 1000
2005 Giant Elwood
ACE Folding Bicycle

gclark8

I have a TA 36 tooth chainring that is a 74mm BCD.

I sometimes run the tri bike 36/42/53.

__________________
Cheers,
George.

climbo

That's a MTB chainring, non-ramped and pinned with a 94mm BCD which is the standard for most MTB cranks. You can see on the chainring it actually looks like it says 94mm stamped right on it but kinda fuzzed out. There is no way that will work properly with your cranks and chain, even if it is 110 BCD.

xxamr_corpxx

Now, assuming it would fit properly and has a 110BCD, by work, do you mean "work to Shimano's standards for non-cyclists who run small-small combinations", or do you mean "work well enough for a sensible cyclist"?

__________________
2004 Trek 1000
2005 Giant Elwood
ACE Folding Bicycle

alfeng

The inner ring on a double does not need to be ramped.

There ARE two minor problems with the particular Token chainring -- the first is that it appears to be DOWNHILL-capable which means that is more robust than it has to be AND, consequently, you are paying an unnecessary premium for the chainring.

As far as the observation that the 94BCD designation was blurred in the picture, I wouldn't worry about THAT because the picture is undoubtedly posted for illustrative purposes [heck, by my count, it's a 32t ring in the picture]; but, if it were truly a 94BCD ring, then it would not work because the bolt holes on the chainring would not match up with the bolt holes on the crank's spider.

You DO have to be concerned that your crank is actually 110BCD (64.7 c-c between bolt holes) compatible and not 130BCD (76.4 c-c) which is the typical size for a road crank (hence, the presumption by previous commentators that the 110BCD ring would not fit). It is atypical for a crank to have a 110BCD 52/39 crank on a ready-to-ride bike from the shop.

Are there any other mail-order sources in NZ?

Is the postage from OZ that much that it wouldn't be worth ordering the "stuff" you need from an Australian mail-order shop?

I'll bet you can buy a "regular" (non-Downhill) 34t 110BCD ring from your walk-in local bike shop for about the same-or-less.

If I had my druthers, I would try to ask the local shop to order a STEEL 34t 110BCD chainring (they may have one in their parts bin) ... there IS a small weight premium, BUT the ring would last forever ... and, I would think that the ring should be under $15NZ because a(n economy) crank with steel rings probably wouldn't cost much more than the cost of that Token chainring.

BTW. A BMX 34t 110BCD chainring would be suitable ... should retail for less than the discounted price of that Token ring. A 36t or 35t BMX ring may be adequate for your needs. Generally, 52/36 or 50/34 are considered to be preferred ranges because of the limitations which the front derailleur might otherwise encounter ... so, getting the 34t chainring would mean that you would probably want to ALSO get a 50t outer chainring!

FWIW. A different cassette with a larger maximum cog would cost about the same as the Token chainring. What are the other components on the bike you are thinking of updating?