SL350 Rebuild (Also For Sale)!!!!!

[honda53rider]

Hey guys im not 100% new to motorcycles im putting the finishing touches to my 1977 Yamaha XS400 that iv been doing a resto/mod on building it into a cafe racer. Im always on craigslist looking at bikes and cars and when my brother was looking into finding a project bike I started looking for him and found a 1973 Honda SL350 K3, The guy was taking bids on the bike and the highest silent bid won. So I gave him a cheap bid and figured I would be outbid. But for the price I knew I could sell the parts or the whole bike for a little profit. So after a week he e-mailed me back saying I got the bike. So On a rainy day me and a buddy of mine got the bike and the title and had it notarized into my name.

So here i am with another project. I am wanting to rebuild it into a endro/dual sport like it was when it was new. No chopping the frame or crazy mods. I want a bike I can take down some of the dirt roads up here around the smoky mnts. But this bike is not my baby so I may also be willing to sell it. (I said sell not give away) I could use some $ to start on another project that I want more than a endro bike. So Im open for offers on the bike, Id rather not part the bike out yet. If I loose all hope ill start pulling it apart.

So here we go!

The bike is almost 100% stock the only things iv seen are the mufflers don't match it looks like one was replaced along the way. The owner before me rode the bike as his first motorcycle and quickly moved on to another bike after only a year. Then the bike sat for 8-9 years in a shed. So he got tired of seeing the bike and sold it to me. I am at school and not back home in my dads shop so my tools are limited. But I have gotten alot of little tings done with the bike. First off was getting the rear wheel rolling. Layed the bike over on its side since i dont have a lift or a center stand. Got the rear wheel off and pulled the brake off and found that one of the brake pads has rusted to the hub. So pulled it off and sanded down the inside of the hub to keep it from any further rust.

I also pulled the cards and out came a funny smelling liquid that i was shore had to be flammable but was not gas. The carbs had the regular slug and buid up but nothing to bad. Don't have any pic of the carbs but they are slid carbs not the CVs like the CB,CL honda 350 twins. (the CV carbs did not work well off road the slids closed when the bike hit big bumps while off road so honda put these slide carbs on the later SL 350's) Also the motor does not have an eletric start and a difrent head to build more turqe. The SL's were a very popular bike on the race track with a stronger and lighter frame and no electric start. (sry for the random history lesson) But i was going to clean the carbs but the carb cleaner broke!?! idk how but it did so ill take it back this week

Also the bike didn't have spark but after a good cleaning of the coils and the plugs i got the one side that had a spark plug boot to pop and should blow up some compressed gas vapor as soon as i can get some carb cleaner. And seems to have good compression but don't have the compression tester with me its back home at the shop. Also the oil and internals look amazing but the bike only has 4K on it so the should look that good.

Thats as far as iv gotten so far. Hopping to have a running bike by the weekend but you never know with old bikes!

 

[honda53rider]

Well iv gotten alot done and im proud to say that iv got a runner! I finely got a hold of some carb cleaner that was not broke and went at the carbs. This is my first time digging into a set of slid carbs but by now i feel like the carb "master" now after going through the XS400 carbs and a few cars and truck carbs but im not.. but i do know enough to figure out the carbs on the SL. So i took them down and pulled them all apart and gave them a good spray. Everything got pretty clean but one of the 2ndary jets was plugged and i couldn't get it to open up. I guess ill have to get one the rebuild kits from online that comes with new jets for $15 per carb not to bad of a deal with brass and the gaskets. So anyway i got the the carbs back on and got the rest of the bike back together.

So i figured that with a little spark on the one side and the carbs as clean as i could get them it might pop a few times off a good kick and would tell me a little bit about the motor. So since i only had one coil with a spark plug boot i only hooked the one carb up with gas. just used a water bottle and some hose to get the flote bowl full and then id give it a kick. So with everything together i started kicking. Took a long time but finely i got something it back fired through the carb not what i wanted but it was something. So i made some adjustments to the carbs and pulled the plug to look at it but nothing major. SO then i got back to kicking. After a few it the motor seemed to spin a little bit longer after i would kick it. (didn't know at the time but it was hitting one time and keeping the motor spinning) So then a few more kicks and it came to life! only ran for a little until the float bowl dried up then it was out. Kept playing with it for a while but was never able to get it to go again. What i missed before is i didn't hear the pop from the motor because of the huge stock exhaust. The bike is very quite and im not used to that. My xs hasvery open pipes and it is LOUD!

So today i called a local shop and ran down to pick up a $3 spark plug boot and also got some purple power for the carbs. My brother had grate results with soaking the carbs he had in simple green. It cleaned the insides and out. The carbs were clean on the inside but grimy on the outside so i figured id try these carbs. Left them in for something like an hour then pulled them out and put them back together. They really did a grate job got the outside close to perfect and the insides were better than before. I felt the bottom of the pot they were in and i could feel all the grit that came off the carbs. So got them back together and back on the bike and got gas to both sides. But both carbs were leaking from the over flow tubes and one was gushing from all over. So ill have to go in again and fix the float needle. But gave it a few more kicks and it started up. Ran a little longer than last night but couldn't get it over 3k im guessing it has something to do with the choke. But when i tried to take the choke off it cut out on me.

So iv got a running bike witch makes me happy after 40 years and almost 10 years of neglect it is back to life. And with only 4K miles i feel like it might have spent most of its life setting and not used a whole lot. Well iv got a short video of it running and home to have it up and going soon but untill then here is a pic to keep me inspired

 

[UNCOILED]

Man I can't wait to get mine running!

 

[honda53rider]

Worked a little bit on the bike, spent some more time cleaning and getting it to look good.

My brother came up to the mountains to spend the weekend riding and wrenching on bikes. So I tried to start the bike and it was doing some funny things!
Something electrical is wrong with the bike and I believe that it will be a simple fix i believe that iv pluged something up wrong in the headlight so it looks like I will be spending some time with the wireing diagram and seeing whats wrong. Also if anyone knows what the two small nipples on the side of the carb are for id love to know. It seems like the carbs overflow and gas comes from the overflow nipple on the bottom of the carb and the two on the sides. So its slow going and my other bike is now road worthy so instead of spending my time on the SL im riding the Yamaha for the last few days before it gets to cold.

But here is a pic of my yamaha the SL and my brothers 78 CB550

 

[honda53rider]

Well i removed the headlight bucket to get at all the wires today took out a wiring diagram and reconnected everything. So tomorrow ill hook a good charged battery to the bike and see how things are going.

Also i moved the gas tank around and found that i like when the rear of the tank sat up on top of the seat so it sat 4" from the original point. I think i like that spot more than the stock mount so i might have to change things up later but iv got a while to think about that.

Stock tank location

Setting on top of the seat (more flat and makes that small gas tank look bigger)

 

[honda53rider]

Well after spending 4 hours playing with wires and rebuilding the on/off switch I haven't gotten very far...

The craziest salduring iron iv ever used

But I think I do know how to get the bike to run! I have to ground the headlight bucket to the forks. That seems to be the ticket. I believe that he forks have 12v on them and they need to be grounded, witch would mean that the on/off switch wires are grounding out somewhere. But for now ill just ground the forks to the headlight and go from there.

After messing with that i got both spark plugs to fire off bright blue sparks! The left side with the original spark plug boot was not working at first but I took the boot off and striped back some more wire and reinstated and got it working.

I was hoping to try and start the bike again but I didn't have any wire to ground the headlight so it will have to wait till another day. But I have a good feeling that the bike will run grate once I get the wiring done. Also iv got to come up with some kind of air filters so I will have pressure in the intake and the bike wont run lean. So for now i think im going to get some clean shop rags and put them over the carbs so the carbs are not sucking open air and they will have to work to get the air they need drawing the right amount of fuel.

In other news I think I know where im going to go with the bike as far as a style, have found the lights I want to run on the bike when i get there. I want to stay mainly stock no frame cutting but I am going to make a 2-1 exhaust and use a dirt bike muffler running up the right side of the bike like some models came with as seen here

Also I think I have found the headlights Id like to run on the bike while on Ebay the other day. I want the bike to look like a baja bike and an enduro bike for the streets so Id like to get these HID lights and run two on the front. There are 6" and 7" pairs for under $120 online. They wont be the best but at least ill be able to see where im going and everyone will see me coming and it will look sick!

So the front of the bike will look like this

 

[Sonreir]

Those are 55W each. That leaves exactly 0 watts to run anything else on your bike.

 

[honda53rider]

Never thought about that how much can the old CB350's take... Iv heard that they don't have the best charging system but where is the happy spot for them. Also another thought was get a very small led light that will pas for DOT for a headlight, and run that at day then just run the big light if needed. Because lets face it i would only use the larger light maybe 5-10% of the time. But I like having the option of having a good light if I need it.

 

[honda53rider]

Well iv gotten a lot done with the bike in the last few days!

First off I got the electrical issue some what sorted. The forks have 12v running through them and the bike wont run unless the forks are grounded. So I grounded the forks the the headlight bucket and everything is working and iv got bright blue spark!

Next I got the bike back together so I could get it in gear and make shore everything is working in the transition (haven't tried running gas out of the gas tank yet so i couldn't really ride) Started the bike up grabbed the clutch and shifted into first. When I did the bike jumped forward and then cut off. After a few more tries with fiddling with the clutch cable I thought it might be the transmission. So I jumped online and started looking up some info, then discovered that is was more than likely the clutch was stuck. The bike could roll in neutral and run in neutral so it was not the trany. So I asked some people on the forum if they thought I was right and they agreed and told me what i needed to do.

So today off came the side cover and I tore into the clutch! I was going to pull all of the plates out and sand them, then oil them before putting it all back together with some fresh oil in the motor.

Started by draining the old oil and pulling off the right side cover. I was afraid that I was going to have a hard time getting the screws broke, I thought I might strip them all but instead they were all very easy to get off. And to my surprise the motor was very clean on the inside. No sludge or gunk of any kind, but the bike only did 4000 miles so may have even be the stock oil from the factory.

I got all the plates out and then went through them by hand to inspect them. None of them were stuck very bad nothing I thought that should have kept the motor from braking loose. But I think that all of them being a little stuck kept the whole thing from working. There was a little rust but not much. I took all of the disc and sanded them then let all of the soak in oil for 5 hours or so while I ran and did some other things and got some 10w40 for the bike.

Tonight even though it was freezing cold I got the bike back together. The clutch cable was a little tricky to get right i still don't think I understand how to set it up right and the cable could use some oil. Before starting the bike I tried rolling it back and forth in gear with the clutch pulled. It didn't want to at first but after a little i got the back tire spinning. I wouldn't call it "free" but it does move. So I started the bike up and let it get some heat in it and let the oil start to move around. After a little I pulled the clutch and dropped it into first. I could feel it pull a little but it was free and the bike kept running and everything seemed to work. So from there I worked the clutch a little. Letting the clutch out till it caught and let it roll back. Then I held the bike back and just let the clutch slip for a while. Once I did this I cut the bike off and tried to move it back and forth in gear with the clutch pulled in. It was rolling easier but not perfect. So I think im getting there. Ill have to get the brakes working well and go for a ride and get the clutch free and working well. But that for another day!

 

[xb33bsa]

did you clean out the centrifugal trap ? its that deally-bob on the end of the crankshaft
good idea to swab it out every oil change

 

[honda53rider]

Nope I didn't, don't know a whole lot about these Honda 350's should probably spend a good day reading a manual. Also I think that these bikes have a oil filter screen in the pump witch ill need to clean but I think you have to remove the right side cover witch I just had off today. So it looks like its coming back off... But its all apart of old bikes. But I am going to try and get the bike running more and let the oil that I just put in move around and clean out any slug that might be hiding in other places before emptying it out to clean the filter and the tap.

 

[honda53rider]

Got the bike even further today! Last night to rode it down the drive way. But I didn't have any brakes to speak of. Well the rear brake pads fell off then I took the rear wheel off the bike, but the fronts had not been touched. They worked but it was more of a touch them and the front end would lock up. But its nice that are driveway is just a hill so ridding up was easy and didn't even need the brakes. But when I did use the brakes they would lock up and not return. So I pulled of the cable and got to work. It was very stiff at first but after working it for 15 min with some chain lube i got it free and moving very easily! So got it back on the bike and the brake was returning fine.

Then today it was off wit the front wheel. The wheel came off easily and the brakes came apart with no fuss. The front hub looked 100% better than the rear. It must have stayed dryer than the rear hub when the bike was stored. So I cleaned everything that I could then took some 120 grit sand paper and scuffed everything up. After I was happy that I got the glaze off everything I got everything back together. Then I rolled the bike back down the driveway to test the brake. And it worked grate. A little softer than I was expecting but im used to disc brakes witch may be a little different. So from there i started the bike and did a short ride around. The bake ran grate and shifted grate as well. It seems like the bike is closer to being back on he road than i thought. Most of the issues with the bike are ascetic and the bike seems to be solid.

I also took a look at the gas tank today witch I have left alone until now. The tank had had some kind of tank liner put into it. Its a think flexible stuff that must of been painted on. But there is rust under the coating and it is making the coating pull up. So it looks like I get to rip it out and clean the tank. Don't know how im going to do it yet but im getting there. As for the petcock I pulled it off the tank today and went through it. It was really clogged with sludge but cleaned up easy.

Coating inside the tank

Here is a list of the things I need to do and parts that need to be replaced to get it road worthy (and just road worthy not finished)

1. Rear brake -new pads and go through the cable like I did the front.
2. New tires - The tires on the bike may be ok to ride on but I would feel much better with some new tires and tubes
3. Gas tank - Some one put a tank liner in it and it needs to be taken out
4. Carbs - They run fine but I need to get rebuild kits with new float needles and one of the idle jets is clogged and needs to be replaced
5. New grips
6. pod filters that are the right size

 

[xb33bsa]

I would not trust the old brake shoes,get new ones or put some rivets in them
what happens is they can come unglued and then you become a ragdoll :'( when the front wheel locks solid, INSTANTLY, ask me how I know

 

[honda53rider]

what do you mean by riveting them? Iv never messed with drum brakes. I know im getting new ones for the rear since they are shot. I can find the ones for the SL k1 and k2s but i wish they had the same as the cb350's since are so abundant. But I sat down and made a list of all the tings I need to get done to get it on the road. First things first the inspector is coming tomorrow morning. He is coming to check the vin number. Just something they do here in NC when you buy a vintage bike or car. Then iv got to get the gas tank worked out. So ill probably order the pads while im working on the tank. But I do want to know how you rivet the pads on! if i don't use it would be kool trick to know.

And thanks for the help!
Also I might be going to look at a 1973 RD350 soon. The bike has 10,000K on it and looks to be in grate shape but sitting for a while. Don't know a lot about 2 strokes but I know ill have to rebuild that bike. But I have to finish this one up first.

 

[honda53rider]

 

[UNCOILED]

Check out this site for jets.

http://www.jetsrus.com/a_jet_kit_street/honda_350_CB350F_1972-1974.htm

 

[honda53rider]

Holy cow that's high dollar for brass! Iv found someone that sells a rebuild kit for the sl350's for $15 per carb with new stock jets. So If I cant get the one idle jet unplugged ill just get the rebuild kits.

http://www.amazon.com/Carburetor-Rebuild-Honda-SL350-1970-1973/dp/B009D0XVWW

 

[UNCOILED]

Well dang, thats a pretty good price. I can't really find jets for the 78 CB550 and that site had them so I thought I would pass it along.

 

[honda53rider]

Well got a little done over the past few days, but not a whole lot. I decided to pull off the spedo today and see if I can salvage it...

The spedo spins when I move the bike around but it stays at the MPH that it was last on. So if i roll the bike forward it goes to 100 and stays. So Thought id pull it all apart and see what I can do. I don't think ill be able to fix it but it was worth trying to working on it and see about saving me another $50. So I tried prying off the ring that goes around the outside and after 20 min I decided to just gut it off! Really don't think ill be able to use it so whats the point in being careful. So after I did this a bunch of rusty water came out of the housing.

After taking a look inside I decided I was just going to wash out the sludge in the sink... So I did and got a lot of it clean. Then took it back outside and sprayed down all the gears with chain lube to keep it from flash rusting and to try and free it up. After fiddling with it for a bit I figured out how it worked (for the most part) There is a wheel on the inside that is turned with the cable and in turn the front wheel. There is another wheel that is inside of the out side wheel that slips by, and this slipping is the key to the whole thing. So I lubed it up and worked it with my hand until the needle would fall back down to 0 MPH when I was not spinning the wheels. So from there I hooked the cable back on and turned it with my drill. When I did the needle spun and fell when I let off. But with my drill it easily hit over 100 MPH so I knew that it was not slipping enough. So I put it back on the bike and shore enough when i rolled the bike forward it would read around 20 MPH. So Any help with this would be grate!!

I do have another spedo from my XS400 that is the same style and size ill have to see if it would work on the SL. The one for the XS has a broken face but I can glue it back together.

 

[honda53rider]

Also found some one who is doing an SL up the same why that I would like to. Its a good read and I really like what he did with his bike.

http://advrider.com/forums/showthread.php?t=226846&highlight=sl350