Sedgemop 

Man, good to know about the 700c wheels. My '85 830 is all the gravel bike I'll ever need. Was thinking about doing something similar for next year's Barry Roubaix.

theblackbullet

Thanks! This bike has been so much fun in any configuration. I don't see it ever leaving my regular rotation.

I actually really enjoy how silly it looks with the 26" wheels, but 700c takes it from an "interesting to look at" bike to something I find quite handsome!

I am using Litepro v-brakes. They can be found even cheaper on aliexpress. They aren't my favorite, but functionally they get the job done. With the pads at the top of the range of adjustment, stopping power is good but not great.
https://liteprobicycle.com/products/...r-modification

Just don't expect too much mud clearance. I think the bike handles great with 700c!

reconnaissance

Hi - some info you might be able to use: the original seatpost was 27.2. The original paint was Dupont Imron (urethane based) and the head tube would have been a deep maroon color. Here’s my 850,




but not necessarily the same year.

Sedgemop 

I think we might need an early mountain bike appreciation thread. 1985 and earlier with lugged forks, slingshot stems, non-generic steel tubing, luxurious geometry, etc. I like seeing photos and hearing what they can do. There's a lot that's right with these early ones.

Hobbiano 

There is this: https://www.bikeforums.net/classic-v...ain-bikes.html

Sedgemop 

Yeah, I'm aware of that thread and it's probably enough, but suspension forks hurt my eyeballs. Thanks.

theblackbullet

Well, it absolutely crushed the gravel race. 120 miles 8200ft of elevation gain and I was able to average 17.5mph with it! I still felt fresh at the end of the ride! But after 1150 miles since June, I guess the frame was just tired.
This is one of the coolest frame failures I've caused. It started as a little play that felt like a loose headset earlier this week. Then on my ride last night it turned into a creak until a nice little pop, I finally noticed the crack after it was completely severed.




Fortunately I have this 1983 520 in my shed. I swapped most of the parts over. It'll help fill the gap while I'm searching for another early 80s tall mtb. I do plan on speaking with a framebuilder about repairing this one. It's been a blast, and there isn't much that compares!

theblackbullet

Oh, and I had just put gears back on it, but left it 700c

JohnDThompson 

The 850 frame used a one-piece, bulge-formed head tube. The pseudo-lug shoreline on the head tube creates a stress riser that is prone to failure, although nearly 40 years service still isn't bad. Repair is likely possible, although the oversize top (1-1/8") and down (1-1/4") tubes may be difficult to find lugs to fit. Fillet-brazed head tube may be an option. Don't expect it to be cheap.

theblackbullet

That is unfortunate.
To clarify, the catalog listed lugs as Nikko Short Point Seamless, but the headtube doesn't actually use lugs? How does this construction work with joining the top tube and down tube?

JohnDThompson 

The head tube is a single piece with the lugs into which the top and down tubes fit. If you pull out the fork and look inside the head tube, you'll see how it works.

theblackbullet

Interesting. I wasn't aware they did this. Thanks for explaining.

52telecaster

So sorry your frame broke but you certainly got some beautiful use from it!

Sedgemop 

I'm thinking about this one for myself, but I can facilitate if you want it.

https://madison.craigslist.org/bik/d...543577022.html

theblackbullet

Thanks for offering! I think after the cost of shipping, it becomes not a great deal for me. I am currently focusing money towards repairing the 850.

Sedgemop 

Sure thing, man. Please post photos of the repair process.

Never heard about the Trek pseudo lug. So, thanks for that, I guess.

pnwgopher

Very cool bike; lots of potential with this one.

merziac

Did you get this?

Sedgemop 

Not yet. Sale post expired, but if it's up next time I'm passing through Madison, I'm getiin' it.

merziac

Make it so.

theblackbullet

Aaaaaand, back from the dead! I placed a Velocals order earlier this month. I'll break it back down and powdercoat it at some point after those come in. Until then, raw for the world to see! Wiped down with some oil should do alright temporarily to keep it from rusting.

Classtime 

So cool and better than new.

Hobbiano 

Can we see a close up of the repair?

romperrr 

Yay! Glad it's back. Beautiful bike and very inspiring.

What was the repair process like?

Larry650

That was my first mountain bike, only a smaller one. It is a good looking bicycle, and a great canal road cruiser.