CM400 Chain, Sprockets, tensioner, impossible to find bolts and more!

The bike has been off the street for the last two months or so as I arduously went through repairs that I did not allocate a lot of time to.

The chain I got on the bike was in rough shape when I got it. The rain of the Northern Arizona monsoon season (17" in three months) did not help. The chain, along with the sprockets and several other parts quickly accumulated rust at a surprising rate. I finally decided to get things going.

A few pictures from before:

The parts list:

• 1 new O-Ring chain. I got it at 120 links and had the crew at my local shop cut it down to 102, which is the magic number for this bike.
• 1 new front sprocket (17 teeth instead of the original 15)
• 1 new rear sprocket (32 teeth instead of 30)
• 1 new left rear tensioner-thingy
• 1 bag of incredibly hard to find M7x1 45mm bolts
• 1 bag of much easier to find M7 nuts
• Incredibly pungent all-around cleaner to help get rid of accumulated debris
• GREASE, which was sorely needed.

I used a couple YouTube videos to learn how to take the bike apart, which was a minor pain simply because I'd never done it before. Probably took me an hour or two to get all my parts and pieces off and organized. Then another 45 minutes cleaning everything near the drive system. Everywhere around the chain area received a thorough cleaning.
That's when the fun started. Getting the front sprocket off was pretty easy, but the rear sprocket the bike had originally was surprisingly thick and came fitted with a guard to keep the chain where it belongs. I could not for the life of me get this damn sprocket off the wheel because of the sort of 3/4 circle lookin spacer thing... (can you tell I'm not a bike mechanic?).

Anyway, I had the shop show me how to get it off and with much grunting, I prevailed.


The old sprocket was spaced perfectly on the rear axle, with essentially no wiggle room. The new rear sprocket is much more skinny than the old one - which leaves me with some lateral wiggle. I could have a new spacer machined or probably snag one from a bike that's a couple years newer.
Well, the new sprocket that I ordered was WAY cheaper and far more available (they don't make the parts for these old Hondas anymore) so I put the damn thing together, tightened everything down and took it for a cautious drive around the neighborhood.

Lo and behold, everything works well! I've done another 100 miles or so since I completed the repairs and everything is working. Time for an oil change and the bike is ready to go into winter storage in my pseudo-garage. Sadly, I don't think I'll get much more riding done this season after this week.

Next time I do the rear sprockets, I'll have a new spacer machined that fits in the space to eliminate that lateral wiggle. Until then, I'll ride it as is.