1970 Honda SL100

Joined
Mar 11, 2007
Messages
373
Location
Texas
Bike
2013 Triumph Trophy
Well, after an inordinately long delay, I'm getting started on the project. Here is my preliminary survey of the bike. Most of the delay was spent collecting reasonably priced parts to actually start the projet. I didn't want to have it sitting around while I looked for a $2 widgit that's NLA.

Picture002.jpg


Picture016.jpg

It's in sad shape--missing lots of hardware, but surprisingly it has the original key and it fits the ignition (which is cut ouf the circuit) and steering stem lock.

It had the wrong fenders, fore and aft, and that didn''t matter since they were broke anyway.

No headlight, taillight, or speedo. Wrong grips (they're trash anyway), left switchgear is missing and right switchgear is broken, and the throttle doesn't seemm to work. It's missing the tool bracket, part of the air cleaner and what's left of that is trashed too.

I've collected the following NOS parts:

Levers and hardware
speedo
speedo mount bracket and hardware
speedo cable
a bunch of misc nuts, bolts and washers
air tube
top bridge
grips
footpegs
fork tubes and innards
swingarm bushings

Picture020.jpg


Picture019.jpg

The wiring loom is cut to pieces, but I've found a good used one for $20. I think I'm going to replace this coil along with the condenser and points and spark advancer. All NOS and readily available fairly inexpensively.

Picture022.jpg


Picture021.jpg

Both rims are wrong--4.00 X 18 back and 2.75 X 21 front instead of 3.25 X 17 back and 2,75X 19 front. There was like 1/4"clearance between the back wheel and swingarm. I've found good used rims and will polish them up and respoke then with the NOS spokes I've found.

Dunlop doesn't make the original tires, but I've found a set of Chinese knockoffs that look a lot like the original tires.

Picture014.jpg

I'll replace the sprocket and countershaft sprocket and chain along with the hardware that holds it in place.

Picture010.jpg


Picture011.jpg

both forks leak and the fork tubes are rusty and pitted. I have found one complete tube including spring, circlip, seal and bottom piece. Still looking for another or the parts individually.

Picture006.jpg

Both shocks are shot--new ones are available in Thailand for <$100

Picture004.jpg

Did I say the grips are bad? Wrong bars too and I haven't found a set of the original unbraced type yet.

Picture005.jpg

The seat cover is bad, but it's better than the seat pan.

Picture007.jpg

This is trash.

Picture012.jpg

It has an oil leak at the head, which doesn't really matter much because I'm going to take the head off and check the piston, rings, cam, cam sprocket, and cam chain. The parts are so cheap it doesn't make any sense to put it back together with iffy engine parts.

Picture003.jpg
It has a funky aftermarket pipe on it. I wonder if it's worth anything? It can't be worth what I paid for a NOS muffler and heat shield. They are HARD to find.

Picture015.jpg


Picture026.jpg

The paint on the tank is about 1/16 of an inch thick, but that doesn't matter since the inside is trash and its the wrong tank anyway. Its supposed to have the "Honda" emblem and not a decal. I've found another that is pristine inside, but has other issues I need to address.

I've collected a better tank, both side panels with all tabs, front and back fender, new air box, chain guard, NOS brake shoes, NOS muffler, NOS tail lightr bracket, NOS headlight, and a good seat.

My first job is to get it running. Stay tuned.
 
I Bought the first one available in our area in 1970. I had it for two years. I believe that I paid about $ 525 :04biker:
 
I ordered a new coil, points, condenser and battery and hopefully will be able to give it a try in ten days or so. I think I'm going to just bodge the current wiring loom to get everything working before I strip it for refinishing.
 
You do fine work Dennis so I'm looking forward to seeing how this project turns out.
 
Wow, you have your work cut out for you in that project.

That looks like a Bassani exhaust.
 
It took me longer to get started again than I thought. I had to service the Wing, then the XL350 started running crappier than it was and I decided to reqally figure out what the problem was with it and that took all my garage time.

Picture027.jpg

The throttle tube moves, but the throttle cable seems siezed. I have a new cable, but no throttle tube so I hope my diagnosis is correct.

Picture028.jpg

the wiring is sliced and diced. I don't trust this coil and I have new replacement; condenser too.

Picture029.jpg

I'm going to try to get the ignition switch working too.

Picture030.jpg

These old bikes hade a selenium rectifier, there are better replacements available, but I happen to have an NOS Honda replacement so I'll use it. I have to put the new battery in because it won't start without a battery.

Picture031.jpg

I hope I can figure out where these go once I put the rebuilt harness back in. I mean physically, there are only a couple connectors so it shouldn't be hard to find out where they go electrically.

Picture032.jpg

I have a new Chinese carb so I don't know if I'll try to rebuild this one or not. It looks pretty bad.

Picture033.jpg

The new battery charging.

Picture037.jpg

Nothing like new parts to get you going. You can clean some up, but others need more than cleaning.
 
I spent a couple hours this afternoon working on the harness. It was a used ebay find, much better than the bike came with. It doesn't take much knowledge to put one of these together as long as you have the right tools which pretty much means a schematic and one of these.

Picture053.jpg


This harness is better than the nonexistent one on the bike, but it has issues too, several wires are broken, a few connectors are missing, the fuse is missing, and a couple wires appear to be gone too.

Picture039.jpg


Picture040.jpg


Picture041.jpg


The first thing I did was take off the plastic tube which protect the wires from chaffing at the steering stem. It's supposed to be soft and flexible, but it was harder than a rock.

Picture044.jpg


The positive battery terminal is missing.

Picture046.jpg


But those are easy to replace.

Picture047.jpg


This brown wire goes to the powers the tail light and needs splicing. This is the oldest bike I've worked on and I was surprised to see that the splices were all soldered. The newer bikes like by '83 CB1100 use brass crimps for the splices. The blue electrical tape below the colored tape on top (gray or black) is the same on the 70s and 80s Hondas I've worked on.

Picture050.jpg


I'm using these crimp splices instead of soldering them, they'll work fine.

Picture051-1.jpg


I had to repair four broken wires and replace a couple ring terminals. I still need to replace a couple bullet connectors (I'll have to order them) and replace the negative battery terminal wire. I'll look for some gray electrical tape tomorrow and see if I can find some type of plastic tubing.
 
My first dirt bike was an SL100, my second an SL125. Good memories. Good luck on putting that POS back together! It'll be good in the end, but...

My ol' indy shop in Downers Grove, IL told me one time they would take the "trade ins" in that condition and just chuck'em in the dumpster. Lots of the earlier Japanese bikes went to an early grave. Hard to find parts now, partly because of that.
 
I have a lot of respect for you guys who can take on a project like that. It's got to be interesting and fun to do a restoration like that, but I doubt I have the patience for it. Good luck!

John
 
My first dirt bike was an SL100, my second an SL125. Good memories. Good luck on putting that POS back together! It'll be good in the end, but...

My ol' indy shop in Downers Grove, IL told me one time they would take the "trade ins" in that condition and just chuck'em in the dumpster. Lots of the earlier Japanese bikes went to an early grave. Hard to find parts now, partly because of that.

POS??!! That's my baby you're talking about!
 
Making progress today, I finished the harness, installed the new battery and new carb. I think next weekend I can change the oil, install a gas tank and see if it runs.

Picture059.jpg

Once I knew the harness would fit I installed the new battery.

Picture061.jpg

The rectifier only goes on one way, I'm not sure why though.

Picture062.jpg

The ground was really rusty, I'm not sure there was any continuity here.

Picture066.jpg

The new coil came with a new spark plug wire, but I had to order the cap seperate.

Picture067.jpg

I couldn't get the cap on because the rubber boot wouldn't let me twist it into place. The cap has a screw inside which should screw into the new wire. I pulled the boot back over itself and was able to get the cap on the wire.

Picture068.jpg

New plug, cap and coil. The old plug looked really good so I contemplated not changing it.

Picture065.jpg

the old coil, it wasn't from one of these bikes and the lead wasn't attached very well. No wonder it wasn't running.

Picture069.jpg

The throttle tube is not correct, but neither are the handlebars so maybe they go together. Once I cut the throttle cable the tube rotated freely.

Picture073.jpg

This is the manifold that goes between the carb and cylinder. There is a hard plastic gasket between it and the cylinder, but this one had some hard black substance and a paper gasket instead.

Picture075.jpg

The manifold cleaned up and the new carb.

Picture083.jpg

The old carb. It was still full of gas, bright green in color. anyone know why its that color? It looks like antifreeze.

Picture079.jpg

Once the carb was on, I attached the cable to the throttle tube and it worked great. After I took the old carb apart I went to put it back together and the return spring is much stronger than the one in the Chinese carb. I'd like to get the original working again.

Picture080.jpg

Carb with throttle closed.

Picture081.jpg

The carb with the throttle open

I'll give it a shot next weekend and see if I can get it running. I'm going to rebuild the engine with at least a valve job, rebore and rings so I just want to hear it run before I tear it down.

I have a list of other things that need done to the engine such as gaskets and seals.
 
POS??!! That's my baby you're talking about!

I don't want to put words in George's mouth, but I think he was refering to what you started with as being a POS. He knows you picked up a sow's ear and will turn it into a silk purse.

Keep it going. The whole line of SLs are favorites of mine. SL350 is still one of the best bikes I ever owned. It was perfect for me at the time. My younger brother owned an SL125 at about the same time and we have lots of memories.......and lots of laughs talking about the good old days on the SLs.
 
I don't want to put words in George's mouth, but I think he was refering to what you started with as being a POS. He knows you picked up a sow's ear and will turn it into a silk purse.

Keep it going. The whole line of SLs are favorites of mine. SL350 is still one of the best bikes I ever owned. It was perfect for me at the time. My younger brother owned an SL125 at about the same time and we have lots of memories.......and lots of laughs talking about the good old days on the SLs.

Actually John, POS is a pretty apt description of the before condition.
 
i juat bought a 71 cl 175 been sitting in a celler for 30 years it has 769 orginial miles i love it

I love the old bikes, especially the 1970-1976 era. Is it a runner or will it need some work?

I got a line on a '76 CB400F that needs some TLC. I'm thinking of collecting one of each 400, 550 and 750 for retirement.
 
Don, make that 350, 500, and 750. The 400 and 550 came later.

I lusted after the SL350 when it first came out (had my 500 4 a the time) but never got one. An indy shop here in town had one last summer, they wanted three times the original price for a not-restored original. Kind'a ruff but not like yur SL100.
 
I love the old bikes, especially the 1970-1976 era. Is it a runner or will it need some work?

I got a line on a '76 CB400F that needs some TLC. I'm thinking of collecting one of each 400, 550 and 750 for retirement.
it runs everything looks brand new on it it just wasnt stored right rims are rustly and tank has a pin hole in it but i cleaned the carb and it fired right off runs like new
 
Back
Top Bottom