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-   -   Anyone have experience with Ofmega crankset? (https://www.bikeforums.net/showthread.php?t=1200663)

mcoate 05-07-20 07:19 PM

Anyone have experience with Ofmega crankset?
 
The Ofmega's have a good classic look to them, how are they? Any other recommendations similar, not looking to get too crazy on price.

79pmooney 05-07-20 07:40 PM

The Avocet cranksets of the day were made by Ofmrga. I bought the triple, thinking like you; good looks, good price. Early on I downshifted to the inner ring to start a steep grade. The long bolts in sleeves for the inner ring broke, I stalled and fell to the low side. Avocet sent me new bolts and told me the originals weren't tight enough, Maybe. That was the days before torque wrenches wrere in bike mechanics' toolchest. But it was also year one of that bike and I;d been riding the erector set TAs for years with no issues at all.

Retired that crankset with quite a lot of miles. 25,000? Pulled it out for temporary use on a bike I had just set up. Broke the crank across the pedal threads coming out of the saddle to top a small rise. (This time no big deal. Stepped down on the road, sat down, braked to a stop, dismounted and couldn't figure out what the clunky feeling of my right shoe was, Pedal still strapped on! This time I was 1/2 mile uphill from my destination; a gathering of friends.

So, long story short - don't trust them with more than you are willing to lose. (I've heard similar stories. It is mot just me.)

Ben

The Golden Boy 05-07-20 07:50 PM


Originally Posted by 79pmooney (Post 21462009)
(I've heard similar stories. It is mot just me.)

I've got one- it's very nice- but I've heard the same stories- well- the breaking across the pedal threads.

As I've heard, it's one of the very lightest triple cranks ever- and where the weight was saved is part of what gives the arms such a graceful shape.

As far as the gearing- I'm not a fan of the 144 BCD- it really limits that middle ring- and for a triple... well...

If you're planning on looking for one- find one with the specific Avocet/Ofmega spindle/BB. I understand the Avocet/Ofmega uses a relatively proprietary taper- and some people have experienced problems with the crank staying seated properly.


https://live.staticflickr.com/4684/3...cda297e6_o.jpg1986 Trek 400 Elance by Dave The Golden Boy, on Flickr

https://live.staticflickr.com/4688/3...7b8e70b8_o.jpg1986 Trek 400 Elance by Dave The Golden Boy, on Flickr

mcoate 05-07-20 08:16 PM


Originally Posted by 79pmooney (Post 21462009)

So, long story short - don't trust them with more than you are willing to lose. (I've heard similar stories. It is mot just me.)

Ben

Ok thanks, that's helpful to know

onyerleft 05-07-20 08:44 PM

BITD we called Avocet, Avoshid. Of course, we also called Shimano, Shidmano, so there's that.

I thought some of the Ofmega cranks were nice looking but I bought only Mavic, Nuovo/Super Record or Dura Ace. Because I have class.

RobbieTunes 05-07-20 09:10 PM

Ofmega Mistral crankset
 
One of the prettiest

mcoate 05-07-20 10:17 PM


Originally Posted by RobbieTunes (Post 21462194)
One of the prettiest

I really like the stamped Competizone ones as well

Bianchigirll 05-08-20 02:15 AM


Originally Posted by mcoate (Post 21461987)
The Ofmega's have a good classic look to them, how are they? Any other recommendations similar, not looking to get too crazy on price.

Bianchi used them a lot in the ‘80s and yes these days they have a nice classic look to them.

However they used a unique taper on the spindle, so unless the seller is including a good condition bottom bracket, or you have a line on one I’d be cautious

read through this. https://www.sheldonbrown.com/bbtaper.html

Chombi1 05-08-20 02:41 AM


Originally Posted by 79pmooney (Post 21462009)
The Avocet cranksets of the day were made by Ofmrga. I bought the triple, thinking like you; good looks, good price. Early on I downshifted to the inner ring to start a steep grade. The long bolts in sleeves for the inner ring broke, I stalled and fell to the low side. Avocet sent me new bolts and told me the originals weren't tight enough, Maybe. That was the days before torque wrenches wrere in bike mechanics' toolchest. But it was also year one of that bike and I;d been riding the erector set TAs for years with no issues at all.

Retired that crankset with quite a lot of miles. 25,000? Pulled it out for temporary use on a bike I had just set up. Broke the crank across the pedal threads coming out of the saddle to top a small rise. (This time no big deal. Stepped down on the road, sat down, braked to a stop, dismounted and couldn't figure out what the clunky feeling of my right shoe was, Pedal still strapped on! This time I was 1/2 mile uphill from my destination; a gathering of friends.

So, long story short - don't trust them with more than you are willing to lose. (I've heard similar stories. It is mot just me.)

Ben

Campy had their own problems with their Record cranksets developing cracks at the spider crank arm junctions.
Also at the pedal holes. Both thought to be caused by stress risers (Sharp edges and corners) on the cranksets. So cracking also happened with the best of them. Same goes with early model 630 Mavic Cranksets.

JohnDThompson 05-08-20 08:26 AM


Originally Posted by The Golden Boy (Post 21462025)
If you're planning on looking for one- find one with the specific Avocet/Ofmega spindle/BB. I understand the Avocet/Ofmega uses a relatively proprietary taper- and some people have experienced problems with the crank staying seated properly.


Originally Posted by Bianchigirll (Post 21462335)
However they used a unique taper on the spindle, so unless the seller is including a good condition bottom bracket, or you have a line on one I’d be cautious

read through this. https://www.sheldonbrown.com/bbtaper.html

Ofmega used a narrower than standard spindle up until about 1980. After that, they adopted the dimensions that became the ISO standard.

romperrr 05-08-20 08:39 AM

Anyone have a way to tell if an ofmega/avocet crank has a proprietary or ISO taper?

79pmooney 05-08-20 09:30 AM


Originally Posted by Chombi1 (Post 21462339)
Campy had their own problems with their Record cranksets developing cracks at the spider crank arm junctions.
Also at the pedal holes. Both thought to be caused by stress risers (Sharp edges and corners) on the cranksets. So cracking also happened with the best of them. Same goes with early model 630 Mavic Cranksets.

Oh yeah. I got to watch two Campy cranks break across the pedal threads in my racing days. Both times from the perspective of the guy on his wheel. (Snuck around both times. Don't know how but I REALLY like super fast steering race bikes!) The Japanese went to rolled threads that were cursed by the mechanics of the day because to mix with the revered Campagnolo, you had to either re-tap the Japanese part or force the fit, (Now, once that is forced a first time, the parts screw together and apart nicely thereafter.) But the Japanese rolled threads were metallurgically right and rarely cracked.

But back to Campy and Avocet. We all knew much of the the Campy equipment when I was racing had many miles of use by very strong riders because that was what there was, Not a lot of choices, (And nobody who was anybody rode Japanese. Just wasn't done.) For a lot of us, money was tight and Campy expensive. Replacing those cranks just because you crashed? Not happening. (Both cranks I witnessed break were ridden by riders considerably bigger than me. And back to Avocet. I weighed 155 in those days, was/is long and skinny and you can pack all my fast twitch muscles in Shaquille O'Neal's big toe. I bought the cranks new. Rode them from ~1982 - '95; maybe 15,000 miles. (A little less than I said in my first post. Memories are coming back.)

Yes, I would have also broken Campy NR the same way because I would have ridden them until they broke, But it would take me 40,000 miles or more to break them. And the much cheaper Japanese pedals, many of which I have ridden to their grave? Haven't broken one yet. (They are officially "dead" when the crank arm is worn to 75% of original from road grit and winter shoes. Or the taper is shot. Or the chainring boltholes elongated. When it comes to the pedal threads, the cheap OEM SRs, Suginos and Shimanos are far more reliable than the classic NRs.)

Ben

Salamandrine 05-08-20 10:16 AM

I used Avocet cranks for a while BITD. They were sort of a weight weenie crank. Lighter than the competitors. I did break one, right in the middle of the left arm. The second set lasted for years and I never had a problem. Old cranks broke sometimes. It's a crapshoot. I learned my lesson after the first broken crankarm. Always inspect your crankarms for cracks on a regular basis. If you do this you won't get a nasty surprise.

Best way to check the taper is to put it on a BB spindle. FWIW I've never actually seen the proprietary non standard taper that is supposed to exist. Avocet cranks weren't available until 1979. It would not surprise me if all of them produced with the Avocet brand were the same and had standard tapers. My cousin worked for Avocet BITD. I'd ask but he's kind of a jerk and we no longer are in touch. Ofmega branded would have been rare. They'd only come in as OEM cranks on Italian bikes.


WRT Campy cranks, you see more cracked ones because that is the crank that nearly all racers used. They are the cranks that got zillions of miles put on them. That used campy crank quite likely has 50,000 or more miles on it. That used SR/Sugino or whatever almost certainly did not. People that did the big miles bought campy because other brands did not hold up, generally speaking.

63rickert 05-08-20 10:27 AM

Back in day of the 1049 and 1049/a crank Campagnolo had a real simple policy. It breaks, we replace it. Didn’t matter if part had been raced, didn’t matter if part had been crashed. No questions, no problems. Those of you who never availed yourself of this policy will have a different view of Campy than those of us who knew.

Second time I broke a crank the exchange was made direct with Othon. I handed him a broken left crank, he handed me a complete crankset. Rings, bolts, BB, the whole thing. “But Othon, only the one arm broke.” Othon replied “Tullio loves you. You ride your bike so much you break cranks. You are the best advertisement Tullio could ever dream of. Take the cranks.” This of course rasped through the trach’ hole together with wreaths of Pall Mall smoke.

Now do you understand brand loyalty?

79pmooney 05-08-20 10:35 AM


Originally Posted by 63rickert (Post 21462997)
Back in day of the 1049 and 1049/a crank Campagnolo had a real simple policy. It breaks, we replace it. Didn’t matter if part had been raced, didn’t matter if part had been crashed. No questions, no problems. Those of you who never availed yourself of this policy will have a different view of Campy than those of us who knew.

Second time I broke a crank the exchange was made direct with Othon. I handed him a broken left crank, he handed me a complete crankset. Rings, bolts, BB, the whole thing. “But Othon, only the one arm broke.” Othon replied “Tullio loves you. You ride your bike so much you break cranks. You are the best advertisement Tullio could ever dream of. Take the cranks.” This of course rasped through the trach’ hole together with wreaths of Pall Mall smoke.

Now do you understand brand loyalty?

I broke two NR track hub flanges riding them year 'round on commuters. Bot times, received complete new hubs, no questions asked. But with hubs, it is more of a mixed blessing. The full rebuild was on me.

Ben

squirtdad 05-08-20 11:16 AM


Originally Posted by Bianchigirll (Post 21462335)
Bianchi used them a lot in the ‘80s and yes these days they have a nice classic look to them.

However they used a unique taper on the spindle, so unless the seller is including a good condition bottom bracket, or you have a line on one I’d be cautious

read through this. https://www.sheldonbrown.com/bbtaper.html

note the taper varies and there is no definitive guide. some are unique, some are ISO, some require an asymmetrical spindle like campy so getting the correct BB can be a huge pain (i got lucky and got one from Bianchigirll and ronald mcdonald house benefited to this day)

Salamandrine 05-08-20 11:57 AM


Originally Posted by onyerleft (Post 21462154)
BITD we called Avocet, Avoshid. Of course, we also called Shimano, Shidmano, so there's that.

I thought some of the Ofmega cranks were nice looking but I bought only Mavic, Nuovo/Super Record or Dura Ace. Because I have class.

Obviously the d was pronounced t... Don't forget Gypme. I'm sure that there's some others I've forgotten.

We called Dura Ace Duracchi in my neck of the woods. It wasn't much respected prior to 7400.

deux jambes 05-08-20 01:02 PM


Originally Posted by squirtdad (Post 21463089)
note the taper varies and there is no definitive guide. some are unique, some are ISO, some require an asymmetrical spindle like campy so getting the correct BB can be a huge pain...

Valid observations! If anyone is bored enough, and had the time to spare, here’s some long winded observations of my own which may or may not prove helpful to others who have banged their head against the wall around the subject...

I purchased a Super Competizione for use with an Italian bottom bracket shell. This was before I realized that determining which bb to use would be such a pain in the butt.

In my quest to figure exactly which bb to to use, I’ve only been able to discover that information is scarce, and unclear in its vagueness. Here’s what I’ve found:

Ofmega is known to have used a uniquely proprietary taper as previously mentioned. This taper is said to be skinnier than other tapers, and apparently attributed to “earlier” Ofmega cranks. The problem here is that there seems to be no guiding factors that identify exactly what “earlier” means, or how to differentiate “early,” from “late” cranks.

Also, if we assume that the later Ofmega cranks which utilize a more common Campy NR/SR style taper are post ‘78, it seems that the spindle length needed for a Competizione is longer than that of its Campy counterpart. According to Velobase, a Super Competizione spindle for an Italian bb shell is 119.5mm, while a Campy NR/SR would take a 115mm spindle.

Making the challenge greater, is the relative scarcity, and expense of Ofmega bottom brackets to experiment with. Most I’ve found over a long search, are on eBay from overseas sellers. I’ve located a couple in the 119.5mm length, but usually the longest spindles available are 118mm. I’ve been scared to buy any of them since they’re expensive, and there’s is no way of knowing which taper I’d be ending up with.

I’m assuming my crank to be “later” Ofmega, since the Super Competizione group was available late 70’s to early 80’s. That said..,

My solution? I’m not entirely sure it’s a problem solver yet, as I haven’t finished the test fit, but I’m taking a gamble on a Dura Ace 7400 bb. The 7400 has Shimano’s “low profile JIS” taper. It’s designed for use with Campy NR/SR cranks. It’s a short spindle at 70-w-113mm, but for whatever reason, it seems to be working. Final torquing of the fixing bolts, and chainline adjustment if needed, will will be the ‘make it or break it’ revelation of course. I’ll be thrilled if it works, and if it doesn’t, I’ll be shelving the crank for something more straight forward.

Here’s the Super Competizione seated tight to an Italian 7400 spindle, but not yet torqued all the way. I predict when finally torqued, the crank will move another millimeter or so inward towards the chainstay. We’ll see how it goes:


https://cimg8.ibsrv.net/gimg/bikefor...c4e43d8b7.jpeg
https://cimg9.ibsrv.net/gimg/bikefor...7e73793f7.jpeg
https://cimg0.ibsrv.net/gimg/bikefor...1418e5ad3.jpeg

seypat 05-08-20 02:16 PM

Could someone give a correct pronunciation of Ofmega? I've always wondered. My brother had a 1974 Vega that we put an 8-9" Glass Pak on. It had a sweet sound!

So, is it Off-Mega like Chevy Vega or something else?

robertorolfo 05-08-20 02:59 PM


Originally Posted by RobbieTunes (Post 21462194)
One of the prettiest

Shhhh. I'm still mad that I passed on a nice set on ebay a few years ago. Seems like the prices have gone up lately.


Originally Posted by seypat (Post 21463351)
Could someone give a correct pronunciation of Ofmega? I've always wondered. My brother had a 1974 Vega that we put an 8-9" Glass Pak on. It had a sweet sound!
So, is it Off-Mega like Chevy Vega or something else?

Pretty much like "off-mega", but you have to pronounce the O and the A in the Italian way. Hard to explain. The final a is more of an "ah" sound than an american "uh" sound.

mcoate 05-08-20 03:01 PM


Originally Posted by seypat (Post 21463351)
Could someone give a correct pronunciation of Ofmega? I've always wondered. My brother had a 1974 Vega that we put an 8-9" Glass Pak on. It had a sweet sound!

So, is it Off-Mega like Chevy Vega or something else?

I have always assumed it's 'Ahv-Mega'

unworthy1 05-08-20 07:24 PM

I have heard it more like "OAF-mega"...by people I assumed were familiar with proper Italian pronunciation

JohnDThompson 05-09-20 06:23 AM


Originally Posted by romperrr (Post 21462713)
Anyone have a way to tell if an ofmega/avocet crank has a proprietary or ISO taper?

Test fit on an ISO spindle. If the arm sits too far out on the taper, it's likely the old-style Ofmega taper. There should only be 3-4mm between the end of the spindle and the base of the extractor hole.

Ferrouscious 05-09-20 06:50 AM

What was the intention behind the smaller taper? To be proprietary? Or was there some performance benefit (however small or misconceived)?

obrentharris 05-09-20 10:01 AM

These were also Ofmega.

https://photos.smugmug.com/Other/Roc...MG_6539-XL.jpg


https://photos.smugmug.com/Other/Roc...MG_6699-XL.jpg

Brent


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