1971 cl100

[benroloff]

Last night I went to see the friend who sold me the bike because he has a friend who just bought his first motorcycle and wanted me to look at the malfunctioning speedo. While I was there he told me that he had found something he thought went with the bike and it turned out to be the right side cover.

I am super stoked that I have a side cover now! It’s only the right side and it’s got a small crack, but since I need to repair the headlight bucket again I’ll just do this at the same time. Other than that it’s almost perfect. Some scratches and stuff but these things go for like $300 for nos! Each!!! And I kinda dig the AMA Camel race series sticker. I definitely don’t want to take it off either because I’m sure all the adhesive from 20 years ago will stay on the paint. Plus now I have something to take measurements off of to potentially make sheet metal ones. So today I sat down for a few hours in fusion360 and came up with this:

I haven’t modeled in the clips yet but I figured it’ll be easier just to make them on the fly if I build these. As you can see I went with a pretty sharp edged design, which doesn’t really match the style of the bike, but I had to design it to where I could build them out of sheet metal with just basic tools and a welder, which I think is doable. They will require a lot of cleanup, but definitely doable.

 

[benroloff]

So I put the cad drawing onto foam board first to see if it would work before I did sheet metal. It looked good so I moved forward with sheet metal. Yesterday it got it all cut out of 22 gauge sheet steel and welded it up. I think when I do the left side I’ll use 18 or 20 gauge. I didn’t realize how hard it was gonna be to weld 22 without blowing holes in it, even with tig. But in the end I was able to get it all together. I backed it with All Metal to give it some extra strength, plus All Metal is waterproof unlike bondo so if in the unlikely scenario that water gets through the paint it’ll only ruin the bondo that I used on the faces of the cover, and not the seams too.

so here it is all welded up and soda blasted in the blast cabinet. As you can see i added the tab on the bottom to utilize the stock lower “mount” on the back of the tool kit.

And here it is on the bike. I like how it looks personally. I think that the sharp lines are kinda cool, despite the fact that they don’t necessarily fit the style of the bike.

I ended up just welding tabs on the frame and and nuts inside the cover. I thought about making clips like the originals but these are a lot easier and will be super easy to remove if I ever decide to. I didn’t really take any pics of the bondo work or primer or anything but that’s what I’m on now. I’m not very good at body work though so fingers crossed it turns out ok

 

[whynot]

wow, nice work...

 

[iatethepeach]

Impressive!

 

[benroloff]

Impressive!

wow, nice work...

Thanks guys. I'm pretty happy with how it turned out. I think I could've done a better job with the bodywork but this isn't a restoration either, so a few imperfections are fine with me. I am planning on getting some stickers made that say CL100. I thought about ones that say honda and have the honda motors wing logo on them but I think that it would look a little redundant to have the covers say honda with the wing logo and have the exact same thing on the tank. I am going to order through https://www.isaydingdong.co.uk/ . They have stickers that say cb125 or 1000 just nothing for the 100cc bikes so I did a custom order through them. Not sure what it's gonna cost yet but if their other stickers are any indication, they should be cheap. I don't know yet how their quality is but i'd definitely recomend checking them out just for the sheer volume of stuff. They have stickers for literally anything. Got the paint and clear shot on it this afternoon. Turned out pretty good but i'm not sure yet how it's gonna match to the tank paint, so fingers crossed...

 

[iatethepeach]

I bought some "Scrambler" stickers for my DIY panniers from those guys.

They were probably intended for a Triumph or some such, but what the hey.

 

[benroloff]

So last month I moved to Milwaukee, Wi from Madison, Wi to play a season of junior hockey. I currently live with what is called a “billet family” which is a family that volunteers to give players a room in their home for the season. When I moved here, I obviously had to leave the bike at home and haven’t had a chance to work on it or see it since I left. But just the other day a opportunity that I just couldn’t pass up fell in my lap. Just 5 miles from my billet house, there was a guy selling sl100 and cb125 parts! I mean what are the odds of that. And since most things are interchangeable with my bike, I jumped on it. I ended up with two headlight buckets, one in perfect shape,

a set of handlebars,

two chain guards,

A stator in really nice shape,

A 125 speedo,

a set of cb175 shocks,

as well as some other stuff like an ignition coil, a rectifier, a chain, a bunch of brackets and hardware, and some other misc stuff. Haven’t really decided what I’m going to do with it all yet but there are a few parts that I’m excited about. I’m considering rewinding the stator for a higher output for a 12v swap. I know that cb350 stators work but I already have this and I don’t want to spend the money on another right now. I am hoping that the cb175 shocks are stiffer than the ones on my bike and that I can find a way to make them fit because mine are just so soft it’s terrible. I also can use the headlight bucket so that’s nice. And I might play around with painting some of the duplicate parts like the chain guard or the bars to see if I can add some accents to the bike. All that said, if anyone is interested in buying any of the parts I listed shoot me a pm. I don’t have my heart set on using anything on the bike so for the right price, I’d probably sell anything and some of it will likely go up for sale in the coming months

 

[Rider52]

Wow! Nice finds!

 

[benroloff]

Small update here, but an update nonetheless. For starters, I got the new side cover painted and put on the bike. I think I’ll start on the left side one this spring maybe. It looks OK on the bike, just not as good as I had hoped, and the color match isn’t great. Eventually I’ll buy the stickers for it and I think that should help. I also got the cb175 shocks set up for the bike. I removed the original bottom mounting brackets off of them and retapped the bottom mounts from the original shocks to accept the 175 shafts, and then splashed some paint on the shock bodies and the spring covers as well. I went with white on the spring covers despite the fact that I’m not a huge fan of white accents, but I think it actually looks really nice. I can also say these shocks are the best $5 I’ve ever spent. They completely change the performance of the bike, and I no longer hit the bump stops over every little bump. Next up is the 12v swap. I have all of the necessary lights as well as a new coil, so hopefully I can get to
that next week.

 

[whynot]

Nice work........I'd like to see how you did the shock conversion.

I just picked up a CL100, and am going to do much the same you are doing........this will be my experimentational bike.......12V, maybe enhance the engine to the extreme, fat tire setup.

Maybe....maybe....maybe.......I'm more interested in getting it running and ridable.

 

[Luugo86]

Nice work man, I like shock conversion, do you have any photos of how how you made it work? Side cover looks good.

 

[benroloff]

Thanks guys, I didn’t take any pictures of the shock modifications but I’ll pull one off of the bike when I have time and try to get some pics. I’m the meantime I found some diagrams so I’ll attempt to explain that way.

So this diagram is of the cl100 shocks, and all your gonna need off of those are the bottom eye, part #1 in the picture, and the little metal insert that goes in the rubber bushing on top, which would be part #11. The metal insert should just pop out with some force, I’m sure you gentlemen can figure that out yourselves. The bottom eye just screws off. It should have some flats on it that you can grab with a wrench, but you’ll have to hold the shock body, part #4 (I don’t really know what this part is called but from here on out if when I say shock body, I am referring to this part) with something. I found that a vise grips with a rag or a cushion of some sort around the body to avoid ruining the shock body works well. After you get these two things off you should be done with the cl100 shocks. The cb175 shocks are where things get tricky. They come standard with the bracket style bottom mount that needs to come off to put the cl100 mount on. The best way I found to do it is as follows: first you should remove the spring from the shock. If you have a spring compressor this would be best, but otherwise you can compress the shock by hand. Once compressed, remove the retention clips, parts #8 in the diagram below, and this should now allow the spring to come off.

This step isn’t strictly necessary but it makes things easier later. Next, as you are looking at the shock from the bottom, there is a nut on the mounting bracket, take this off. An impact works best as it means you don’t have to hold the shock body (the equivilent of part #4 in the cl100 diagram) with anything, but the vise grips with a rag works here too if you need to use a socket with a ratchet instead of the impact. Now, unfortunately, the bottom mount doesn’t just fall off, because it is actually welded to the shock body. What you should do is cut a slot on the threaded rod that comes out of the bottom of the shock to fit a flathead screwdriver. Make the slot pretty big as you will need to put some decent torque on it. Once you have the slot you can turn the rod clockwise while holding the shock body from rotating. This will unthread the shock shaft from the bottom mounting bracket as well as the shock body. You should now have the shock body and bottom mounting bracket separate from everything else. Now that you don’t have the threaded rod to worry about you can just cut the bottom bracket off, I found that a sawzall with a metal blade worked well for this but I’m sure an angle grinder would work well to, just be sure you dont remove too much material from the shock body. Once you’ve done this you can thread the shock body back onto the shock shaft using the groove you cut into the shock shaft earlier to tighten it down, and put the spring and spring retainers back on. Now you can get the cl100 bottom shock mounts out and get those ready. All you need here is a 9mm x 1.25 tap and the appropriate drill for that tap. I got the drill bit and tap for like $9 at my local hardware store. Drill the old threads out of the cl100 shock mount and re-tap it with the 9mm x 1.25 tap. You can now thread this onto the threaded shaft of the cb175 shocks, if I recall correctly I had about 6 or 7 threads of engagement, witch for a thread this size should be more than enough. At this point you should be done with the bottom mount, which is the hard part. Now you just need to press the metal sleeve from the cl100 top mount into the top bushing of the cb175 shocks. It isn’t a perfect fit, but I found that a little heat on the rubber bushing helped a lot. You should now be able to mount your cb175 shocks on your cl100!
I hope this was helpful, but I imagine it was a little hard to follow unless you have the shocks sitting in front of you while you read it, but I’ll try to take some pics when I have the time and that should help clear things up. Feel free to ask for help if you need

 

[benroloff]

Nice work........I'd like to see how you did the shock conversion.

I just picked up a CL100, and am going to do much the same you are doing........this will be my experimentational bike.......12V, maybe enhance the engine to the extreme, fat tire setup.

Maybe....maybe....maybe.......I'm more interested in getting it running and ridable.

I think you’ll love your little 100, i sure love mine. How do you plan on doing the 12v swap? I’ve heard of some guys just putting in a better rectifier and a 12v battery and lights and that working well (this is my plan) and I have seen others swap in a cb350 stator as well as the other stuff mentioned above.
what kind of engine enhancements were you thinking? I’ve had a hard time finding performance parts for these things. I have heard that you can put on a head off of an xl200 I think it is, but other than that it seems like it’d pretty much be custom if you want to do anything else

 

[benroloff]

Today I walked through a local shops parts stash, if that’s what you want to call it. It’s really two decent sized buildings full, floor to ceiling, two levels, with parts. Pretty much all makes and models, though mostly older Japanese. There’s really no organizational system so you just have to look through everything until you find what you want. I didn’t get anything today but I’m gonna go back when I have more time. I’m thinking about trying to find a flatslide to retrofit to the bike. Probably a 24mm. Is this an awful idea? I’ve heard that flat slides can be tougher to tune, especially from scratch, but I’ve also heard that they tend to flow better and are snappier. I’ve never seen one on an old Honda 100/125. Let me know what you guys think!


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[Rat_ranger]

You can probably get a crf150f carb or a 24mm round slide and get the same performance. The only 24mm flatslides are chinese copies of the PWK. I have one on my xr100 big bore motor, jets are easy to find, needles and slides are a different story.

 

[benroloff]

You can probably get a crf150f carb or a 24mm round slide and get the same performance. The only 24mm flatslides are chinese copies of the PWK. I have one on my xr100 big bore motor, jets are easy to find, needles and slides are a different story.

Do you think there’s actually any performance to be gained by swapping carbs? I don’t ever expect this thing to be a powerhouse, after all 100cc and a 51 year old engine only gets you so far, but I wouldn’t mind a little extra kick. I don’t particularly care to dump a ton of money into the engine as the gains will only ever be minimal, but if a carb upgrade would actually help I would definitely do that. Just seems like the intake port and valve is probably a bigger bottleneck than the carb?


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[whynot]

I've heard a CB750 piston can be used in these engine............I think.....Not really sure if it's these....

 

[benroloff]

I've heard a CB750 piston can be used in these engine............I think.....Not really sure if it's these....

They can... sorta. Bore out the original cylinder to fit a cb750 sleeve, amongst some other machining work to make it all fit together. You also need a crank out of a cl/cb125, or you can just start with a 125 engine. The 125’s use a connecting rod with a larger piston pin than the 100’s, which is needed to fit the 750 piston. I suppose you could rebuild a 100 crank with a 125 rod, or maybe ream out the hole for the piston pin in the stock 100 rod. You’d also want to probably do some extensive work to the head to account for the extra airflow, a bigger carb obviously too. I would consider attempting this project one day just for the fun of it, but i imagine it’s a rather expensive procedure


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[Maritime]

It's easier to just swap a Lifan 250 in.

 

[pidjones]

It's easier to just swap a Lifan 250 in.

Agreed. Stressing old metal with higher power is risking a lot of issues. However, I saw a recent F9 video indicating Chinese engines had the most particulate contamination (beyond normal acceptance criteria) upon delivery, so flush well before starting.