Bushyboy's build thread

So I have an issue which I have been troubleshooting and reading lots of information on the forum. So with all this reading I think I am narrowing it down to the magnet on the stator. My issue is that after about a mile of two down the road in or above forth gear the bike will die. Even letting off gas and down shifting or putting in neutral and coasting had no effect on bring it bag to life. It was like a slow game over bogging down not really like a gas or air choke. I would have to pull over let it cool down kick it over until it decided to run enough to get me back to house and then it would die again. It Idles just fine before I take it for a drive. The battery wasn't charging during the drive either. I have been going through the troubleshooting of the charging system. With a cold idle and 2000 rpm test it was showing 14.6v on the battery. I did see one of the brushes was worn more then the other and close to the 7mm so I ordered new ones. One of the resistance checks indicated my stator may need to be replaced. My reserve fuel line gets slightly loose when warmed up too, so I plan on replacing this as well. I looked on the radio shack website and they didn't have the rare earth magnet in stock. Anyone know where I can get one or any advice on this issue?
 
Dying when hot can be a bad coil. Sometimes when they go bad, they only act up once hot, work fine again once cooled down.

14.6 volts at the battery when revved is charging. Test at idle and then when revved up. No change between the two means no charging. High output all the time (14.5 to 15 volts, or higher), regardless of RPM, usually indicates the regulator isn't working or working right. It's not regulating or limiting the peak charging output like it should. If it's stopped working, the alternator is being allowed to run full blast all the time, and it's output can climb quite high as the RPMs do.
 
Thanks five twins I will look into it today. I think I got all the way up to the coil continuity checks so I will do them today; as well as check voltage just at idle. The only reason I say it wasn't charging is because I checked the voltage after It died the second time and it had like 11.5v on the battery. It is a new battery that has been properly charged and I even put it on the charger to get it up to 12.6v before the test ride. Another thing I forgot was strange was the half lean / half normal plug on one side. My brake indicator light is constantly on when ignition is switched on and riding, but I am sure I need to find the wire that is grounding for that.
 
Last edited:
Key on, not running will often drag the battery down into the 11's. You have several items drawing power out of the battery and no charging going on (because it isn't running) to feed power back in.

There's really no way to test for this bad coil thing, or at least no easy way. Testing the coil itself when cold will most likely result in good readings. You would need to test it immediately after the bike dies, before the coil cooled, and that's not always easy to do.
 
I unplugged the 3 prong brake flasher unit. If your running an Led light it can also make it flash, you can fix it by adding a diode resistor.
 
Made a lot of progress today and a minor setback. Figured out how to get the led turn signals to flash coordinating with the switch. Just had to ground the flasher wire and pull the turn signal bulb. Removed the light checker; which fixed the brake indicator light staying on, and also tossed the canceling unit. Retorqued my head since I had a minor leak and snapped the fricken oil banjo bolt. Installed one size larger main jets and new brushes in the alternator. Got my andrews coil in the mail. Gotta figure out a way to secure it now. I hope this fixes my cutting off issue. Today woud have been a great day to ride it was 60 degrees.
 
Last edited:
Made a lot of progress today and a minor setback. Figured out how to get the led turn signals to flash coordinating with the switch. Just had to ground the flasher wire and pull the turn signal bulb. Removed the light checker and auto light shutoff. Retorqued my head since I had a minor leak and snapped the fricken oil banjo bolt. Installed one size larger main jets and new brushes in the alternator. Got my andrews coil in the mail. Gotta figure out a way to secure it now. I hope this fixes my cutting off issue. Today woud have been a great day to ride it was 60 degrees.

"Installed one size larger main jets and new brushes in the alternator"

..........I'v .always had trouble tuning my alternator, now i know to adjust the jets:)...............sorry couldn't help myself
 
Went to check something on my old ignition coil and one of the spark plug boots just fell off. Maybe it was that simple and just my luck on this build. Oh well continuing on fabricating the mount bracket for a new higher voltage coil. I do look forward to easier starts and so does my starter.
 
Yes, a loose or bad spark plug cap connection could very well have been the cause of your intermittent cut-outs. Here's how I prep the ends of my spark plug wires to insure a good connection. I strip about 1/8" of insulation off the spark plug wire end and fan the strands of the inner wire core out in a radial pattern. I then brush some dielectric grease on the wire end and about 1/2" up the sides. Then finally, the wire goes into the coil or has the plug cap installed .....

VqkZjYD.jpg
 
Just reading through this thread. In one post by Paul Sutton He described his way of aligning cam bearings.
Just wanted to say that's wrong. You must slide the cam bearings on as far as they will go. Then set the cam on the head with the same distance on the out side of bearings to the outer surface of the head. This holds the cam centered in the head. This aligns the cam sprocket with the crank sprocket.
Doing it Paul Sutton's way will allow the cam to slide back and forth sideways and cause excessive wear on the can chain and sprockets and guides.
Yes the inner sets out in free space a bit. That's ok. their are two bearings on each side to carry the load.
Leo
 
Thanks for your advice @XSLeo I did align my Cam the way you described because I followed JimD54's tech guide along with nightflyers YouTube videos and my trusty maintenance manual.
 
Done correctly, cam alignment is automatic. When RobinC (rip) was having sealing issues on his fresh top end, I pulled a rocker box from an engine and measured. The green arrows below show where I tried to insert a .0015" feeler. It wouldn't fit at any point. In other words... with the point and advance housings properly seated, there is no room for misalignment.

IMG_20180716_111536.jpg
 
It looks like you have no gaskets on those points/advance housings? That would allow them to sit in tighter and push the bearings in more. With gaskets, they may not push the bearings in as far. Maybe that small amount due to gasket thicknesses wouldn't effect cam chain/sprocket alignment much. I'm going to investigate this eventually because I'm hoping to find a little space in there. I'd like to seat the cam seals in a hair more if possible, to give them better "purchase" on the ends of the cam. This would mean making them hang out the backs of the points/advance housings a little bit. But, a little space will be needed in there to do that.
 
It looks like you have no gaskets on those points/advance housings?
Yeah... that was without a gasket. Just checked a Versa... it was about .035". So yeah..... you could get a 35 thou. misalignment... which would be insignificant. Even so, I think I'll amend my top end thread to reflect that.
 
But, is that .035" per gasket which would that mean .035" per side? .070" total side to side play?
 
And now back to your regularly scheduled program. Fought with finding the best location for the ignition coil where the gas tank didn't deny me. Went from an almost oem looking bracket to I don't care it's secure.
 

Attachments

  • IMG_20190203_154536.jpg
    IMG_20190203_154536.jpg
    148.1 KB · Views: 189
  • IMG_20190203_154525.jpg
    IMG_20190203_154525.jpg
    123.5 KB · Views: 240
But, is that .035" per gasket which would that mean .035" per side? .070" total side to side play?
It means .035" left or right of centered..... .035" max offset. I added this info to the buildup thread.
 
Yes, I see that now. The cam could be free to move .070" total side to side but it would only get .035" off center in either direction.
 
There's a bit of an issue with the two large wiring looms that run down each side of the frame and up into the headlight. Due to their size and weight, they slowly sag down and pull themselves out of the headlight bucket. Yamaha was kind enough to put a couple small holes in the gusset plate behind the steering neck and you can use those to feed some cable ties through and create a cable harness "sling". Stick one through from each side so you end up with a male and female end on each side. Join them together around the harness and snug them up enough to support the two harness runs from sagging .....

QsA2ljz.jpg


AKNpZnn.jpg


The above pics are from my early, first rendition "mod". Within a few years, the sharp edged holes in the frame gusset plate cut through the cable ties. I now install rubber grommets in the holes first, cable tie cutting problem solved.
 
Back
Top