Thursday, April 16, 2009

1974 Honda CB125S


Another bike with very few miles on the odometer that made its way into Barry's garage for some restoration. It was first seen on Craigslist, then on eBay, where it was snagged for slightly less than the seller was asking on Craigslist. New tires (of course), new clutch and throttle cables, and a new ignition switch cable were the first changes. The carb was cleaned and adjusted, the timing chain tension adjusted, and now it starts on the first kick and runs strong. (It's getting a tuneup and detailing now and then owner Mike is putting it up for sale.)

The CB125S is a simple OHC thumper that was imported into the US from 1973 to 1985. It'll cruise at 55, and easily gets 100mpg at slower speeds. These bikes will last for many years so long as you're absolutely religious about changing the oil at least every 1000 miles- preferably every 700. The one weak point of the engine is the cam shaft bearings, which are simple journal bearings machined into the head. Once they wear, you can either have the heads machined to take roller bearings- a project that will cost several hundred dollars- or simply find a new head.

The CB125S was replaced in Asia and Europe with the CG125, and almost identical motorcycle that featured a simpler pushrod OHV engine in place of the CB's OHC engine. This was reportedly done to make the bike more rugged for use in the third world, where oil changes can be an expensive luxury. The CG125 engine develops slightly less power, but top speed and mileage are similar.

11 comments:

  1. Where did you get new tires for it? I just bought a 1975. Can't find any tires that will fit online.

    Anything would help. Thanks!

    rosswelborn@gmail.com

    ReplyDelete
  2. I ordered the tires- Cheng Shens- from JC Whitney! They're pretty much identical to the originals, and cost around $30 each.

    ReplyDelete
  3. Any chance you could post a front on picture of this bike as well? I did a bunch of custom work to mine and forgot to document the original before I started working. Or if you could just email me a front view pic to tyler.myers@gmail.com I would really appreciate it!

    ReplyDelete
  4. What is he planning to sell it for?

    ReplyDelete
  5. Asking price is $1400 when it's fully restored to showroom condition. Until then, the price is negotiable.

    ReplyDelete
  6. Does anyone know where to get a seat pan for this bike at?

    ReplyDelete
  7. hey i'm interested in buying this honda if it is still up for sale. is it?

    ReplyDelete
  8. I have a '76 CB125S that doesn't get ridden much because the battery won't stay charged. Yep, tried new batteries. Help? Stator or some other part of charging system? Typical problem? I'd consider selling. Thanks.

    ReplyDelete
  9. After checking to make sure the grounds and wire connections are all good, I'd check the selenium rectifier. Sometimes they last forever, but they can fail. Replacement with a modern silicon rectifier assembly is cheap and easy.

    ReplyDelete
  10. Battery upgrade: I installed electronic ignition, and the BikeMaster 6V 6Amp is too weak at low RPM's. How high can I go on Amps on this bike?

    ReplyDelete
  11. where can a person try to find a gas cap for a 1978 Honda cb125s, I am having a dickens of a time

    ReplyDelete