1989 3.0 Mtb build

Found a frame (cheap!) on Ebay; 16" frame with fork, headset , bottom bracket and triple crankset. Have had a lot of fun riding my Bridgestone MB-Zip so I thought this would be a perfect project for a rebuild. Received the frame, found it missing one cantilever stud on the frame; removed the crankset, bottom bracket and headset (totally congealed grease!), repacked the bearings and thought about the rebuild. Serial # 0169809016...that makes it a 16" frame, September 1989 frame #16? Decided to go with V brakes, single chainring. Ordered cantilever studs and found out that while the standard M8 studs are close, Cannondale, in their infinite wisdom, used SAE threading on waterbottle bosses (10/32!) and 5/16 x 18tpi on the cantilever studs (though, oddly, the inside threads are metric and the flats are 8mm...go figure). Ordered the SAE studs from Vintagecannondale, threaded them in and found they were about 2mm too long. Jeez. Broke out the dremel tool and cut them down (titanium is tough). Decided to strip the frame and repaint...
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black lightning 1987

Moderator
Staff member
You have interpreted the serial number correctly I think. I had forgotten the 1989 frames were 130 mm spaced but as they were mostly 6 speed I guess it makes sense. I don't know why they used 5/16" threading but they weren't the only company to do so. Nice project.
 
It's done; 23 pounds fully built; not too bad. Could shave some weight with a better crankset. Took it for an initial ride around Mt. Tam; October 30 and it's up to 80 in the sun. Just need the decals and trim out the zip ties to finish.
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black lightning 1987

Moderator
Staff member
That's pretty light for a 1980s frame. Hope you will put pink decals on it.
Thanks for the ride photo. I didn't realize that there was that good a road up Mt. Tam. Where did you start the ride? Is it safe to ride Highway 1?
 
Proper photo with a layer of dirt on it.
Need to dial in the shifter/derailleur; running the SRAM GX 10 speed derailleur and shifter. Just got to adjust the stops and cable tension. Did 13 miles/1600' climbing yesterday and 21 miles/1400' climbing today. Riding at about 21 PSI to help smooth out the bumps. Warm weather in California.
Saddle has got to go. Ouch.
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That's pretty light for a 1980s frame. Hope you will put pink decals on it.
Rode to Natalie Coffin Greene park, which is the entry to Phoenix lake. Rode up Eldridge Grade, then down Indian Fire Trail. Steepest part of the climb was a 17 or 18% section, steepest descent was over 20% and rutted. Eldridge goes all the way to the summit. Highway 1 is better for road/gravel bike riding. Lots of fire trails up and down Mt. Tam; you should come out and ride it sometime.
 

black lightning 1987

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Staff member
What's your lowest gear? Looks like it might be a bit lower than 1:1. Can you ride an 18% grade? Local gravel rides have some short 10% sections. While I can get over them with pretty conventional vintage bike gearing, 18% is more than I can imagine riding - perhaps even on pavement.

I'd love to ride out there some time. When I was in the area for work there was never any time for riding. I'm no longer traveling for work and the family that used to be in Oakland and Walnut Creek have moved back east. Nice to think about though.
 
running an 11x42 on the rear and a 34T front. In retrospect, might have been wiser to use a 32 on the front, but I could muscle up the 17+% dirt section...trick is to get the rpm up to where you can maintain it, not blow up and keep it steady. The minute you have to stand, you're hosed and lose traction. Much harder to do when you're 64...had to stop and catch my breath after the grade eased.
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black lightning 1987

Moderator
Staff member
I've had that experience on rough steep gravel and a low gear that wasn't low enough. You have to stay seated to have enough traction but don't have enough power to keep pedaling. That's when a nice ride turns into a nice walk. I learned that Look Delta pedals aren't the best choice for gravel riding.

I'll have to look at my bikes and see what my lowest gear is. I might have 30/36 on one of them, which would be almost as low as your 34/42. I don't think I could ride a 17% grade with that gearing.
 
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