996

Hi guys. Just trying to better understand the type of steel used in my bike.

double butted which is cool. What does this compare to in modern day steel frames?

was this a higher end frame back in the day? Thanks!

Bianchigirll 

SuperSet II is a Bianchi thing that refers to how the frame is built. The Down tube is slightly oversized and then ovalized at the bottom bracket shell and also uses heavier gauge chain stays. Most of these tubesets were custome made for Bianchi. SuperSet II tube sets were used from basic recreational level bikes up to the top of the line Japanese and Italian built frames.

As to the quality level I would need to know more about the frame, is there a model name on it? I think it comes from '90 or '91 judging from the style of that sticker.

996

Thanks for the info! The bike is a Bianchi Forza

madpogue 

As for the OP's last question, re. analogs to modern day - other than for the stratosphere of the market, is there any such thing as CrMo or MnMo frame tubing made outside of China?

Wildwood 

Bianchigirll , and all Bianchi knowledgeable, How would the Ishiwata SuperSet compare to the Tange version???

let me find the pic.
Bianchi Limited - early/mid '80s. Not the lightest frameset, but in this size for a 200# rider, was very, very good. Well balanced handler.

Oooopps, this is SuperSet, not SuperSet II. I know it is a mixed tubeset, just not what thicknesses.

Bianchigirll 

Sorry I just had to post this. But in a way it is true, how do you answer the 'which is better question'. If you know the exact metallurgy of this tubeset and the comparable Tange tubeset you might be able to mathematically prove one is better than the other but in blind ride test it comes down to the opinion f the rider.

The main difference between SuperSet and SuperSet II is the oversized and ovalized downtube.

Bianchigirll 

The Forza was an entry level (recreational) bike that originally came with a mix of Shipmano Exage 400EX and 500EX and all the 600 stuff and wheels on this were added later.

I agree with Madpogue that there is little to compare it to in most modern bike lineups. I belive most bikes in this price quality range are now alloy and mostly hybrids and mountain style bikes.

PS: this looks like it might be too small for you.

T-Mar

Given the era and level the Forza is likely a combination of Tange 900 and 1000 or similar entry level, seamed tubesets.

T-Mar

As you note, Bianchi's Superset II is a mixture of two tubesets. Superset was introduced for the 1984 model year, which was also the last model year for Piaggio, so your bicycle would be a 1984 model. The serial number will provide confirmation on the model year. Bianchi stated that the 1984 Limited used Ishiwata 022. I'd assume that this is the primary tubeset, as it this would be the most advantageous approach from a marketing standpoint. The down tube would likely be heavier gauge Ishiwata 024. However, since 017 though 024 all used the same 0.8mm chain stays, the Superset chain stays would be custom drawn. To the best of my knowledge Bianchi did not use heavier gauge tubesets on the larger Superset frame sizes. This can be confirmed by the seat post size, would typically be 27.2mm if 022 was the primary tubeset.

So, assuming an 022/024 mix, your frame should have 0.9/0.6/0.9 top and seat tubes with a 1.0/0.7/1.0 down tube. The fork blades would be 1,0mm. The seat stays would be 0.8mm. The chain stays should larger than 0.8mm standard used on 017 though 024. I'd assume custom drawn 0,9mm, as their 0245 used 1.0mm and it was hi-tensile.

An Ishiwata 022/024 Superest configuration would be comparable to a Tange #2 /#3 Superset configuration. Unfortunately, Bianchi did not identify the Tange tubesets used on the later versions of the Limited and identification is further complicated by the fact the Tange used a common seat tube for their #1 , #2 and #3 tubesets. An Ishiwata 022/024 Superset frame would be virtually indistinguishable from a Tange #2 /#3 Superset frame of the same size and geometry.

Wildwood 

Thanks TMar, 022 is the primary tubeset, a heavier gauge downtube plus stays is what it felt/rode like and seems common for nice mid-range bikes, especially in larger frame sizes.
@Bianchigirll i'm excellent at bs, a lifetime in sales/business development. Was seeking tubeset comparison.
FWIW, i liked the Limited so much, i had to get another Ishi022 bike, which is the 78 Batavus. I think the Batavus is 022 for all tubes, but never had the frames or bikes side-by-side for a weight comparison.

Thanks for the responses.

Now back to SuperSet II and Tange talk.

996

Bianchigirll Appreciate the input. Yeah I added all the Shimano 600 components to the bike from an old Cannondale I had laying around. The frame might be a bit too small, but that picture angle also makes it look like it may be too small for me.

The bike rides very well. Just wondering if I can fit 28C tires on there...

Also I am a bit concerned about the bowing/bending top tube.. is this normal with age?

Thanks again all!