1981 C70 Front end issues

[#AWMB]

Hi all! This is my first post, but I've been reading a lot of the others and they are sure helpful.

I recently picked up a 1981 C70 from my cousin and it's been mostly in great shape. He wasn't too mechanically inclined and I've been trying to sort out the few issues here and there with the Clymer's and a service manual- but there are still two things going on in the front that I can't quite fix.

1) The front fork is probably bent. With the bike sitting up straight while on a lift and both wheels in line, the front wheel has an angle that causes the top of the wheel to lean towards the inside of the fender. With the handlebars at a slight angle, the bike rides straight and is stable and the wheel only rubs when the bike is turned full lock to the right. There is a bunch of evidence that it has fallen: grips chewed up, front fender rack askew and mounting bolt bent along with other cosmetics. The handle bars are also at a tilt when the wheel is pointed straight and when I removed them I could see the top bridge was bent. I've ordered a replacement from ebay that is straight and also replaced the front shock absorbers, but kept the same suspension arms/hardware.

One thing I noticed though while replacing the shocks, are that the rubber shock dampers at the bottom of the forks are manually set to a certain position before being tightened. I saw in the service manual how to arrange them and in doing so, the wheel was re-centered evenly between the two forks. However, once I took the bike off the lift and sat on it, the wheel when back to that tilted position. Would I be able to fix that by playing around with those dampers or perhaps replacing the suspension arms? Or is this a sign that fork is bent?

2) The front brakes don't grab. I've checked the pads and they are not at their wear limit (more than 2mm left- the bike only has 4200 mi on it). I tried adjusting the nut above the brake cable and it helped grab a little, but not enough to stop the bike while moving w/ rider. I even tried rotating the brake arm further out so the cable would grab more brakes but that didn't help. I then replaced the front brake cable and installed everything back to spec but still the same issue. The new brake shoes I have don't have much more lining than the current shoes that are installed, so I'm not sure what to try next. Any ideas or similar issues regarding front braking problems?

Thanks for any ideas or input/experience with these. Like I said, the bike runs fine and I can stop okay with the rear brakes around town. I just am trying to get it all sorted. Anyone know of some replacement front end, I may be interested.

 

[69ST]

Easiest way to verify how much fork legs are bent is placing them, one at a time, on a flat surface, then rolling them. Something is really waay off, going by what you posted above.

As for the brakes, those old shoes may not be worn out but, they are old and the vintage friction material doesn't seem to age gracefully. It could be combination of oil/grease contamination and rust. First off, replace those shoes. I've seen many examples where the friction material separates from the shoe and that's dangerous. Contaminated friction material is useless and there's no way to clean the petroleum residues that likely have soaked-in deep. The drum surfaces should be scuffed with sandpaper, then solvent cleaned. I'd check the ID of the drums; the wear limit is 111mm, as i recall. If they're close to that, it's going to take a long time to seat new brake shoes. If they're at, or beyond, that spec, which is unlikely, you need new drums. The problem is that as the drum ID grows larger, less brake shoe contact occurs, until the friction material is worn-down near the center.

2mm is less than 50% of the original brake lining thickness.

 

[kirrbby]

I'm not familiar with the C70. We do have a few C70 guys here on lilHonda tho, maybe someone will chime in.
The front forks look to be made of sheet metal, and the way that the front wheel mounts is a little different for sure.

I would think you'd need to remove the front fork completely, lay it on a flat surface, then try to figure WHAT is bent, and HOW it's bent.

Maybe it's just something out of place, missing, or worn out. If it's actually bent, maybe a good used replacement would be the best bet. Or, maybe those sheet metal parts could be nicely re-straightened..?
eBay is a good place to find used parts.

Getting the forks straightened out might help the brake problem too?? Again, I'm unfamiliar, I'm not sure how the brakes are actuated on that front end.

 

[#AWMB]

Thanks y'all for the insight. Some new developments, but still the same problems-
@racerx - you were correct about 111mm. That was stamped inside the wheel hub and when measured, the ID was 110mm. So it's barely within limits, but was very smooth- I'll try scuffing it up soon. I did replace the brake shoes this time around though. What is weird is that after replacement and adjusting the front brake cable, it still doesn't activate the brakes when the lever is fully depressed. I wonder if both cables were the wrong length? or if I'm better off just trying a new front wheel.

@kirrbby - I ended up ebay'ing another set of forks and transplanted my suspension components into it (shocks, suspension arms & rubber damper/stoppers) and it surprisingly had the exact same issue. There aren't any bends on either fork it seems, so perhaps the original forks were fine and it has something to do with any of the old components- suspension arms, rubber stoppers or the wheel perhaps.

I might try swapping the rubber dampers to opposite sides to see if that is causing the tilt in the wheel. That would be the easiest replacement now. Or maybe one of the suspension arms is crooked/causing the tilt. Back at it again tomorrow...

 

[69ST]

Move the brake arms by hand. Do the brakes engage? If they do, then you may either need less inner cable stick-out length...or...try re-clocking the arms, by one spline, moving the arms farther forward.

 

[#AWMB]

Front end all sorted out!!

@kirrbby The tilt in the front wheel ended up being the suspension arms attached at the bottom of the shocks. After ebay'ing another pair of those, I luckily get to keep the original forks attached and even added an SP Takegawa front damper. With the new shocks, arms and the damper, the front end feels brand new and more stable.

@racerx The brake arms were engaging by hand and working well without the cable, I ended up adjusting the arm a few teeth past the indicator point so the cable engages the brakes further. Seems to work great now.

Thanks for all the help and suggestions!