Kona Caldera Serial Number List - list updated 11/09/23

One factor I don't think we've dived into very much is, what did Mountain Goat have access to / what were Mountain Goat using up until they ceased to exist (in name)? I wonder if there was a surplus of some tube-sets and they were renamed to something generic so not to alert the actual manufacturers.
One factor I don't think we've dived into very much is, what did Mountain Goat have access to / what were Mountain Goat using up until they ceased to exist (in name)? I wonder if there was a surplus of some tube-sets and they were renamed to something generic so not to alert the actual manufacturers.
Normally I could put something together rather better to do some more effective comparison, but I'm not so tickety-boo right now, and have left the harder work to whoever may feel the need to wade through these pictures.

Yes you are correct regarding the tubing that was used for the confirmed seven Caldera frames that we have seen so far. What we see, is a variance in the Bulge of the Seat Tube at the Bottom Bracket Junction in these frames. Needless to say, they are likely to be left over Mountain Goat stock, and renamed after Jeff's MG Company folder in 1995.

Anyway...... elmadu: CA9609021, Molotov Red 16”, and your CA9609046, Poopsy Blue, 20" have no Bulge:

1997 Caldera 16 CA9609021_5.jpg

While konaman1: K09610031, Poopsy Blue, 18" does have a Bulge - Prefix notwithstanding to account for anything 🤪 !

1997 Caldera konaman1 18_2.jpg

I can add some pages from the Tange Catalogue to see if that helps with identifying any tubing - I should get the whole catalogue added to Archive.

1997 Tange Cat 17 18.jpg

1997 Tange Cat 19 20.jpg
1997 Tange Cat 21 22.jpg

1997 Tange Cat 23 24.jpg

1997 Tange Cat 25 26.jpg

Fill your boots:

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1997 Caldera Frame Serial Numbers:

Hand made in USA by Altitude Cycle Technologies.
Featured in the 1997 catalogue, but some say never sold to the public, although I think this is a bit of poetic licence. Kona says approximately 50 were built in (Poopsy) Blue and 50 in (Molotov) Red.
Made from Heat Treated "Altitude" Cromoly steel tubeset. Left over Tange from Mountain Goat perhaps?
The weight was quoted at 4.0lbs, the same as the Explosif, and the frame listed at £549.95, £50 more. The Caldera was however part the Kona Custom Frame Program, and a full £250 less than the Hot and the Ku. Kona were apparently responding to the public’s desire for an affordable Custom Frame.

• mrdryskull: H0 9607032, Different blue, 19"
• VanIsle: CA 960901#, Unknown Blue 19"
• Bigttown: CA 9609012, Poopsy Blue 16”
• elmadu: CA9609021, Molotov Red 16” 1,999gr
• al-onestare: CA 9609046 , Poopsy Blue, 20"
• knickering: CA 9609144, Molotov Red, 18"
• konaman1: K0 9610031, Poopsy Blue, 18" – Formerly H1v9a8c8
• E-Bay listing Molotov Red 16” – no confirmed serial number (not CA9609021)

I believe this is from Dan Capek at Kona:
Quote, "I was running our custom program in Canada at the time so pretty plugged into the facts.
I'm about 6 computers/OS past those days though so some of this I need to pull from memory. In Canada we had 50 red and 50 blue frames and 100 kits for them. You could get a frame, a frame and fork, or a frame fork and kit. The US would have had a similar number. All the custom frames were routed through the US warehouse to Canada and Europe but I can't say how many they got; it could have been the same number or none at all."

Wow that's some X-files level stuff there. OK let me fill in some of the blanks.

The Caldera in it's custom form only lasted for one year because people didn't want a budget custom bike. We had a whole run of options on the custom program and the buyers were people who'd progressed through riding and wanted a "best" bike. There were also unlimited colour choices on the Hot and Ku while the Caldera was red or blue.

The riders with that budget would look at the U'hu, and the Kula and Explosif and go that route.

So I suspect the rarity in the UK is because no one wanted one and not many came over there.

The tubes were picked out by Altitude. Altitude was Jeff Lynskey's expansion past Mountain Goat; stuff like the dropouts were used because they're a super nice investment cast item and they fit smaller tubes vs. our bigger dropouts. It's definitely not an 853 frame. We'd build tons of custom frames and hold them raw ready for paint, then when we'd get low on stock we'd see who had the time and space to produce another run. That's where you'd see the changes in builders for the steel and alloy hardtails.

It's one of those bikes that we built because riders would tell us they dreamed about having a custom bike but couldn't afford it. So we built an affordable custom. Turns out that's not what they wanted; they wanted XTR and all the bells and whistles. Same reason as that huge surge of Chinese and Russian Ti frames died off so abruptly. People really didn't want them.

So if you do find a Caldera it's neat handmade bike to have for sure. That was just at the point of a huge change in riding. Before that you'd start on a hardtail and progress to nicer and nicer hardtails till you plateaued with a Ti frame. Then suddenly suspension came along and started fracturing the process. Then full suspension started to move out of the curiosity category into the must have bike, and then disc brakes came along and people really pulled back from custom frames and paint and poured all their spending money into functioning upgrades vs. good looks."

To be continued:

Here's one I picked up off of FB Market Place few months back. Knew it was kinda rare... However, here is the kicker. SN CA9609158. Size 18.


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Important update on page 1 concerning the future of this thread and registry


I think I have one to add from a few months back so please bare with me :LOL:
You won't get many updates to this thread, but another 97 Caldera has come to light, so the list is updated.


No photographic evidence of the SN which I'd love to have because, if it is #158, then that means they produced another batch of 50 that we didn't know about, making at least 150 produced in total.
Quite a Caldera week because CA 9609181 has come to light.




It's appearance is explained by the new owner:

The story I got from the seller was he came from out west in 1999(?) and was looking for a Bridgestone MTB. Went to bike shops but couldn't find one. Bought this bike from a "bike shop dude" who said it was as close to, or better than the bike he "wanted". Anyway, it was his commuter bike ever since then, with all the parts as is from the original owner. Perhaps this was just a "frame" only build by the "bike shope dude".

I bet my mortgage it was absolutely a frame only build. #181 means we have to adjust the production run to at least 200, all made in September 1996, from the original estimate from Kona of 100 (50 red, 50 blue). What a development!
Wind up the klaxon, we've reached double figures! Thanks to Maxwellllll we now know of 10 1997 Calderas and crucially, to date, he's the first "owned from original" example. Even better, it's in the gorgeous Molotov Red.

CA 9609109 Molotov Red, 19" (maxwellllll)



Number 109 puts it firmly in the middle of the total production run, which we now know was larger than the originally stated 50 blue, 50 red.