himespau 

Is there a way to tell the difference between a Tange chrome-moly and a Tange mangalloy fork?

I've recently acquired a cannondale touring frame/fork, and, from the serial number code, I can see it was made in 1984, meaning it's either an '84 or '85 model. I'm trying to figure out (from curiosity, it doesn't really matter) the model number. If it's an 84, it is either an ST-500 or an ST-300 (which as I'm reading the catalog was identical, but just the frameset). If it's an 85, it's either an ST-400 or an ST-500, which only differed in fork and components mounted (which doesn't affect me as I only have frame/fork).

The frame is red of some hue or other and both were offered in red (ST-400 was fire engine red, but it all looks red to me). The only markings on the fork itself that I can see is where it says Tange 4F, Made in Japan.

The person I bought it from called it an '84 ST-400, but I can't see that they sold an ST-400 in 1984, but it could be a frame they made in 1984, but was a 1985 model. Or he misspoke and it's an ST-500.

In the end, it doesn't really matter, I'm just curious. Either way, it's a nice-looking frame that I hope to build into a decent rider for my wife. It won't be taken out on any tours, so the fact that it's going to have caliper brakes rather than cantilevers won't matter (and, in fact, should make the switch to 700c wheels easier).

gaucho777 

Not sure if this will help in this case, but there is a great Tange catalog (though from '88) on velobase. Toward the end there are lots of detailed photos & specs for different Tange forks.

https://velobase.com/CatalogScans/Tange_1988.pdf

himespau 

Thanks, didn't see a any fork crown that was quite right. I'd been hoping for something easy like learning that mangalloy wasn't magnetic or the steerers were *****d or something. Since my wife's not a vintage person who cares, I guess I'll just not worry about it.

JohnDThompson 

In general, the higher-end forks will have investment cast crowns and forged fork ends. Look for a weld seam on the bottom of the crown; if you find one it's not investment cast. Forged fork ends tend to be thicker than stamped ones, and usually have a manufacturer name stamped on the face. Post some pictures of the bottom of the crown and the fork ends if you're unsure. Here's the fork page from an early 80s Tange catalog:

himespau 

Well the sloped fork crown lug does appear to have a seam on the underside or at least a bump on both sides (pretty well hidden by the paint) where as seam would be - probably 1/8" wide. On the other hand the dropouts appear forged (Tange TL is stamped on them). It is a touring fork though, so maybe all touring fork dropouts are forged so that the eyelets can handle the weight of a loaded front rack?

U5512

I don't have an answer for you, but I have an '87 / '88 model year SR500 (which I am currently restoring) that has Tange 7.G and Made in Japan engraved on the steerer. According to vintage Cannondale Catalogs, my '87/'88 SR500 has Tange mangalloy fork.

xuwol7

I have 2 Peugeot bikes with Tange 2001 Magnaloy forks and frame and I find them to be very durable and bullet proof.
I believe it to be Chrome Moly 4130.
They ride like a dream and make excellent touring bikes.

They are a vintage Canyon Express and Urban Express and would never sell them

JohnDThompson 

No, "Champion" was Tange's chrome-moly tubing; "Mangaloy" was a Manganese-Molybdenum alloy similar to Reynolds 531.

himespau 

Hmm, that sounds a lot nicer than I'd thought. I was figuring it'd be more like HiTen given the seamed fork crowns.

kc0yef 

I have a Tange that has Reynolds fork legs and Tange Steering tube

miamijim

I believe the cro-mo steerers are stamped as such.

JohnDThompson 

Yes, Tange was completely willing to build forks to customer's specs. It's likely that your steer tube is also Reynolds; Tange stamped all the forks they built regardless of whose tubing was used to make them.

kc0yef 

Ough.. now I am going to have to look and see if there is reynolds stamped somewhere on that fork it came without a frame but it had a 250mm steering tube so I snapped that one up at recycled cycles in Seattle for My 64cm KHS TRI-A

himespau 

I haven't seen a Reynolds stamp anywhere on the fork, but it might be there somewhere under the paint. I didn't notice the stamping on the dropouts until Mr. Thompson told me to look for it.

I have another, probably stupid, but kind of related question to my original about using the type of fork to identify my frame. How do I know whether I need nutted or recessed brakes? I've only ever worked with cantilevers before (with the exception of one bike that does have recessed dual caliper brakes). The frame (a cannondale ST400 or ST500 from 1984 or 1985) either came with "New Shimano 600 EX regular reach", "Modolo Flash regular reach", or "New Grand Compe side pull" brakes depending on the exact year/model according to the catalog. Are those all obviously one or the other, or could those be either from that time frame?

Does the fact that there isn't a flat face on the rear brake bridge and the fork crown is a bit rounded unlike the example in U5512's picture mean I need nutted brakes?

miamijim

The mounting hole for nutted brakes will be the same ID on both sides of the bridge/crown. For recessed brakes the hole on the wrench side will have larger ID and will be countersunk.

Forks can be either or regardless of the crown being flat or rounded. Rear bridges are more than likely nutted if it's a rounded bridge but could be either or if it's a flat sided bridge.

JohnDThompson 

Post some pictures and we'll likely be able to figure it out.

himespau 

I didn't have my calipers with me at the time, but my tape measure (not the most accurate) made it look like they were 6mm holes on all sides and the scuffing on the rear brake bridge looked more like a convex washer than the bite of a round washer that I have on my bike that has the recessed nut. If I remember to take a camera in to where I have my frame/fork, I will take some pictures. Thank you.

If they're nutted, I have some Dia Compe 610 centerpulls with new Kool Stop Continental Salmon pads that should fit that I took off the frame that I was originally going to use for this build. Are those good enough stopping power, or should I look for some nutted Tektro R559s? I need ~63 mm reach in my brakes.

onespeedbiker

The 1985 STs came with "low rider" rack bosses on the fork about 1/3 up from the dropouts; the 84 did not. I would also say that there is a big difference between red and Fire Engine red; I had a Fire engine red 1985 SR900 and it was truly the color of a red Fire Engine.. The catalog also decribed the 85 ST500 as having Tange Chromoly with Fully Sloping Crown and came in Fire engine Red; and the 85 ST400 having a Tange mangally (fork) with "low rider bosses" (I believe the 85 ST500 also had the "low rider bosses" and came in regular Red, but Fully Sloping Crown may have been unique to the the ST500. The 1984 catalog only spec'd the ST300 with Tange 124B, Chromoly with Fully Sloping Crown and came in regular red; it's unknown if the 84 ST500 came in a different color or not. Between the "low rider" rack bosses and difference in reds, you should be able to figure out what fork you have..

himespau 

Huh, I hadn't noticed the lack of bosses on the 1984 or the ST500. I guess 1985 ST400 it is because my fork has them.

himespau 

So the holes appear to be the same size front and rear. Best as I could measure it with my calipers the rear brake bridge hole on both sides was 6 mm. The holes on the fork crown both appeared to be 6.4 mm.

Some pictures:





That makes it sound as though I need nutted brakes, right? Originally, I was going to build a bike up for my wife on a different frame, but that turned out to be too small, so I bought this frame for her instead. I'd hoped to move all the parts over (except headset - that's JIS, this appears to be ISO - and seatpost) and do it on the cheap. I had thought the centerpull might work as I need 63 mm reach and the one I'd measured was 60-75 mm and nutted, but it turns out the catalog for that bike (a 1980 Fuji Gran Tourer SE mixte) says that the bike came with Dia Compe 610 brakes, so I'm guessing it actually came with 610 and 750 brakes and I only measured the rear. I'll have to measure them both tonight to make sure. If I'm lucky and they're both 750s, I'll just need cable stops. If one is a 610, I'll either need to get another 750 and some cable stops or a set of tektro R559 calipers which might be better anyway (though not cheaper than using what I have).

himespau 

That color seems true to me. Is that Fire Engine or regular red?

kc0yef 

Sand Cast & Investment Cast Strongest
3D printed (not sure where these fit yet)
Forged
Stamped weakest

More about Fork crowns with pictures...
The Retrogrouch: Lovely Fork Crowns

WNG

Interesting! From the stuff I've read, I was under the impression Tange Mangaloy tubing was a cheaper grade offering than their Cro-moly line. And it was alloyed with Manganese only, no molybdenum like 531. A step up from hi-ten, but heavier than cro-moly tubing.

But since you're a frame builder, you must have had access to tubeset specs from the factory and know every little detail!

JohnDThompson 

Yes, it looks that way. Tektro makes some still.

elfoam

The magnaloy frames weigh the same as Tange infinity (2300g). Its supposably very similar to 531 but thicker/stronger, bit heavier too (300grams). I like to grab the magnaloy frames because its a very underrated steel and you often find them cheap. Its definitely lighter and harder than your typical 4130 frame. 26.6m seat post.