New xs400 problems.

[Onetype]

Started the bike today with the new petcock to test everything. I still cannot get this headlight to light up, I've got it on a on/off/on toggle switch from the relay. Tested the power wire to the switch and didnt get any voltage. If I hook it directly to the battery it works so I know the light is good.

I already asked this question but didnt really get a response. Do i need the relay since I have it on a toggle switch. I mean I can leave it off until it gets warmed up and running and then I can flip it on.

 

[XSLeo]

I think your bike has a headkight relay.This relay keeps the headlight off untill the bike starts and the alternator is producing electricity over about 4.5 volts.
When you start your bike and the alternator starts producing eclectricity some of this electricity is sent out on the yellow wire to the relay. When the voltage on the yellow wire reaches about 4.5 volts the rfelay trips and sends power to the dimmer switch.
Now if the alternator is not putting out any electricity the yellow wire gets no voltage, so the relay can't trip and send power to the headlight.
Have you checked the alternator output? What is the battery voltage at idle and at about 2500 rpms?
If you get good readings on the voltage, That's about 12.5 to 13.5 at idle and 14.5 volts at 2500, and never go over 14.5 volts at any rpms And the headlight still won't get power then the relay may be bad. At the relay there is a yellow from the alternator, a black, that's ground, a red/yellow and a blue/black. With the key on you should get battery voltage on the red/yellow wire. With the engine running, the yellow wire should have, over 4.5 volts AC. The voltage on the yellow wire is from before the rectifier and is AC. Proably 11-20 volts AC. If the yellow wire has voltage the relay trips and sends power out on the blue/black wire to the dimmer switch.
This is on a stock wired bike.
Check your voltages and lets figure this out.
Leo

 

[Onetype]

Alright that was my idea earlier but I got sidetracked. I dont have a working tach so no way to tell really what rpm I'm at. On my bike its a white wire that comes from the alt, anyway I went out and started it up and checked the volts and I was only getting like .5.

This is the wiring diagram that I have been using, seems to match my bike perfectly. As you can see there is a diode somewhere in that wire. I remember seeing one of these when I had the wiring apart. Is it noticeable when they go bad?

 

[Onetype]

Took me a while to locate it but here it is, I think? I tried to get a tone through it but didnt get anything even when I switched the probes around. Also tried testing it on the diode setting, got a reading of 560 one way and nothing the other. Does this sound like its bad? Pulled it out of the plastic sheath and it physically looks fine but im unsure.

 

[WulfgartheBlack]

Onetype,
Can't tell from the picture but a diode is supposed to pass current in one direction only and sometimes they have a pointed end in the direction of flow - sometimes a painted ring around the outgoing end. Does sound like maybe the relay is the trouble. Anybody with and old Cadilac will tell you that fun-derfull automatic gadgets - fail.
Aircraft have pre-flight checklists and a pilot who's supposed to know what he's doing rather than trust some hidden gadget to work every single time. Cadilac drivers can thumb a ride when one of those toys goes out or just live with it - pilots, not so easy.
Like old Caddies, our machines [and some of us] are way past the expected lifespan and lots of stuff that used to be good enough just isn't up to the job anymore.

It means one more thing on your checklist, but bypassing the relay and using an A/B/Center-Off toggle switch looks like the most trustworthy way to get contol of your headlight's Hi/Lo/Off.
I'd drill a hole in the headlight bucket to mount it - just for short wire-runs and I'd solder the jumper and pigtails with bullets in and out if the switch has solder lugs. Screw contacts take a bit more space but seem easier for most folks to do.

You might get lucky and find a 'new' left-side switch-cluster and a working relay on Ebay and use the factory wires.

Be lucky or skilled - Both if you can swing it.

 

[Onetype]

Thanks for the info, I ran across someone else who ditched their relay as well. Cut it out and just ran the wire from the fuse to the switch. Seems to work, we'll see how it holds up.

I was able to get my old tire off but ill be damned if I can get the new one on. Tube is leaking air and the underneath of the rim tape was all rusted so looks like I have some things to add to the list.

....almost there

 

[XSLeo]

Most diodes have a 10 times rating. ohms one way should be at least ten times ohms the other way. So your diode is fine. I was looking the diagram you posted. I was looking at a 79 diagram.
In yours they just branched off one of the white alternator to rectifier wires, to the diode then to the relay. In this case they used the diode to rectify the voltage to the relay.
From the looks of things you get power to the relay from the headlight fuse on a red/yellow wire. If you remove the relay and install a jumper from the red/yellow wire where the relay plugged in to the blue/black wire in the same plug this will send power to the dimmer switch.
If you are using the stock dimmer switch, then you could, instead of a jumper run wire from those wires to an on/off toggle switch. Then you could turn the headlight of while starting.
Leo

 

[Onetype]

I unplugged the relay, cut the blue/black and red/yellow wires then soldered them together. Wrapped the rest of the plug in the harness. This is what im using for the headlight switch, 10a on/off/on toggle.

Now about the tube. I know i'll probably get some shit for this but ya'll should know me by now, I like to save $ where I can. It has a small tear. Never tried to patch a tube before but should I attempt it?

 

[lhaolpa]

No,I went to the county clerks office.Being an old guy,bearded,and I guess very honest looking helps,as the lady just had me sign an affidavit,and said the title would be sent from Nashville. I did have a bill of sale with serial#s on it from a company saying the bike was sold as,for parts.I told the lady that I built it from a raggedy frame with a few parts falling off,and she went from there with it.It's a small,rural county,so they rely on the T.B.I. to figure out if it's stolen. lha BTW,this is in answer to Medmund's post.sorry for off topic post!

 

[lhaolpa]

Get a new tube with a new tire. You'll wish you did,having said that,I've done it before,and it worked,but I'm lucky. A tube is cheap compared with sitting on the side of the road with a flat! What I did when I took my tire to see the rust on the rim was to wire wheel the rust away,then treated the rust with some phosphoric acid product,and when through curing,sanded smooth and painted with rusty metal primer,then enamel. With a new rim band,tube,and tire,it was go!I always put the first side of the tire on,then carefully allow the tube to air up by removing the valve,then stuff the tube carefully into the tire,making sure that you won't have the tube in the way of the tireirons,and I keep checking for the tube moving toward thee rim.I then air up the tube,let it deflate,then put the valve in,and air up and go! lha

 

[Onetype]

I wire wheeled as much as I could off then I sprayed the rim with that rust converter and then used an enamel over it. I dont know why, this may be me but nothing is ever as easy as it should be when I need to do it. All the videos I see online show someone just popping the tire back on no problem. I couldnt even get the first bead over the wheel. I had maybe like 4-5 inches left that just would not stretch over, I tried for most of the day and finally gave up. Im putting a 130/90-16, the tube I pulled out is a 5.00/5.10-16. Does this sound right?

 

[XSLeo]

That's the right size tube. 130 mm is 5.00 inches. Is the tire warm? A warm tire stretches more and goes on easier. Use a lube. A 50/50 mix of liquid dish soap/water works.
Some even use WD40.
On patching a tube small holes can be patched anything more, replace the tube.
Some places saving a fed pennies is ok. Things like brakes, and tubes are NOT the place.
Leo

 

[Onetype]

Man, my friend mentioned something about heating the tire up too. I didnt think I would need too though. I think im going to patch the tube and keep as a spare. Its super small, took me a while to find it.

 

[Onetype]

Got the rear tire done, still waiting for the front to come in.

I had a hard time getting it to run without the choke today. Once it would the exhaust was popping quite a bit, basically just running like crap. Is this a symptom of just sitting too long without really running it?...Seemed to do better the last time I started it for the day. Im starting to wonder just how reliable this thing will be. Sometimes it runs real well, sometimes it doesn't.

 

[Onetype]

After a night of fighting electrical gremlins, I think I got it under control now. Put my old headlight in and it seems to be working fine.

The last thing I need is rear brakes, I haven't been able to find any except at bike bandit and they want like $30 for them. I know Mikes carries them at an awesome price but they are out and no clue when they will get more. Anyone know where else I can find them?

New tires

 

[lhaolpa]

Try powersports.com,motorcycle superstore,dozens more if you google motorcycle parts. lha

 

[XSLeo]

www.vintagebrake.com Ran by the same Micheal Morse that runs 650central.
Leo

 

[Onetype]

Ordered some from oldbikebarn. Sucks they make you spend a minimum of $25.

Anyway, got some good news today. My title came in, just waiting for the brakes to show up and I can take it up to get inspected. My plan right now is to register it as an antique.

 

[xschris]

Its always nice to have the title

 

[Onetype]

Finished all the paperwork today, got my plate.

I rode it around a bit and it runs good. When I first start it, sometimes I get a small backfire but then its fine, no backfire or popping while im riding. It idles real well when you first start it too but I noticed as I was getting close to home after riding a bit, it was idling high. Im at 50 pilots, 147.5 mains and 2 turns out on the mixture screws with pod filters and open exhaust. Pulled the plugs and they are pretty black. I haven't messed with the needle height yet (I didn't know you could).