rezsst
XS650 Addict
I just read on here about glue Ing a rare earth magnet. I'm thinking this could be my problem.
Is there some way to test the stock magnet.
Thanks
Is there some way to test the stock magnet.
Thanks
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pick up coil magnet
- Thread starter rezsst
- Start date
rezsst
XS650 Addict
I did a vom test on the pick up coil a few months ago and it tested good. Can I rotate the rotor an test it. Not sure what it would read on the vom. Bike only acts up when its hot. That is a sign of a bad magnet.
ippytattoo
Just another grumpy old hack.
Hell, they are only like $3 for a pack of 2 of them at radio shack. If you think it is a weak magnet it is a cheap test.
rezsst
XS650 Addict
I'll stop bye radio shack on my way home. Is there a part number or some dimension. Our radio shack dosen't stock much.
Thanks
Thanks
ippytattoo
Just another grumpy old hack.
rezsst
XS650 Addict
Very cool thanks
I know this fix works for some, but here are my observations:
The space between the rotor and the pick-up is too thin to allow simply gluing a new magnet on top of the old one. (A local respected and knowledgeable expert says that you need to partially grind out the old magnet.)
I took a thin feeler gauge and stuck it on the rotor magnet and then stuck it on a new Radio Shack magnet to try to compare the strength of the different magnets. Did this with two CDI rotors, and decided my original rotor magnets are fine.
The space between the rotor and the pick-up is too thin to allow simply gluing a new magnet on top of the old one. (A local respected and knowledgeable expert says that you need to partially grind out the old magnet.)
I took a thin feeler gauge and stuck it on the rotor magnet and then stuck it on a new Radio Shack magnet to try to compare the strength of the different magnets. Did this with two CDI rotors, and decided my original rotor magnets are fine.
rezsst
XS650 Addict
OK. Ill check it out. I was wondering about that. My ongoing stumble. Got an extra bike to swap out parts. But seams to be it.will swap out the Tci this weekend if I can wait that long.
IIRC this was a "fix" for an imported new replacement that was being marketed for awhile.
The replacement was thinner placing the magnet further away from the pickup. The magnetic field produced by the rotor at higher rpms was overpowering the the signal for the pickup. But it wasn't a problem for the thicker stock rotors OEM or rewound. IIRC. . . .
The replacement was thinner placing the magnet further away from the pickup. The magnetic field produced by the rotor at higher rpms was overpowering the the signal for the pickup. But it wasn't a problem for the thicker stock rotors OEM or rewound. IIRC. . . .
rezsst
XS650 Addict
Very good information, thanks. Think I might swap out the rotors , stator and tci. I'll get the magnets just in case I need them. Could be a bad wire somewhere.
to bad I cant use a vom while driving
to bad I cant use a vom while driving
http://www.xs650.com/forum/showthread.php?t=30582
rezsst, for what it's worth, look at the above thread, especially the very last post which I just made.
rezsst, for what it's worth, look at the above thread, especially the very last post which I just made.
rezsst
XS650 Addict
Dam dogbunny your killing me. And your right, but I still have to try, just cant let it go.not yet. I'll waste another weekend doing the swap.if I don't get any results then its pamco time or harness or key switch.
The symptoms, runs perfect then stumbles then good again, mostly when its hot.
what I've done, when it stumbls it floods, went thru carbs many times. Using a spare set re jetted with brass floats and works great, tci re soldered, replaced reg/rec, old one was bad , vom everything was good, new high output coil, new fuse block, new led tail light, new petcock, new headlight,
there it is I'm doing it again. Dam it.
Austin is cool, former Dallas resident
The symptoms, runs perfect then stumbles then good again, mostly when its hot.
what I've done, when it stumbls it floods, went thru carbs many times. Using a spare set re jetted with brass floats and works great, tci re soldered, replaced reg/rec, old one was bad , vom everything was good, new high output coil, new fuse block, new led tail light, new petcock, new headlight,
there it is I'm doing it again. Dam it.
Austin is cool, former Dallas resident
I was going to say classic coil or TCI symptoms, then you said you replaced the coil and re-soldered the TCI, so now I say you have the unsolvable problem I had.
Wiring is very easy to test by running a hot wire directly to the coil. For convenience put a brand new toggle switch in the wire, otherwise you will not be able to turn the bike off. Put a fuse in the wire for safety. You don't have to subtract or change any existing wiring. Do the exact same thing for the TCI, run a hot wire with switch and fuse directly from the battery to the TCI red wire. Only other thing to check as I recall is grounds, in particular the TCI black wire, and the spade connectors in the white terminal blocks.
I am very familiar with the Pamco install, so for me, the whole thing with the advance and rod and bushings and setting the timing took about 90 minutes after jacking with the bike for 9 months...
Wiring is very easy to test by running a hot wire directly to the coil. For convenience put a brand new toggle switch in the wire, otherwise you will not be able to turn the bike off. Put a fuse in the wire for safety. You don't have to subtract or change any existing wiring. Do the exact same thing for the TCI, run a hot wire with switch and fuse directly from the battery to the TCI red wire. Only other thing to check as I recall is grounds, in particular the TCI black wire, and the spade connectors in the white terminal blocks.
I am very familiar with the Pamco install, so for me, the whole thing with the advance and rod and bushings and setting the timing took about 90 minutes after jacking with the bike for 9 months...
rezsst
XS650 Addict
More good information. Thanks for your help.
This bike is my gas saver.save about $400 a month.
Dogbunny . Thanks again for your help.
This bike is my gas saver.save about $400 a month.
Dogbunny . Thanks again for your help.
Last edited:
rezsst
XS650 Addict
Swapped out the TCI and run good. Going to go for a ride when its hot outside to make sure.
I see you have it fixed, but one way to test for a weak magnet is to fully charge the battery, unplug the reg/rec and go for a ride. If it runs ok the magnet is weak.
With the reg/rec plugged in the rotors magnetic field can be stronger than the TCI magnet. The Pickups sense the changing magnetic field as the magnet passes by.
With the reg/rec plugged in this change in the magnetic field as the magnet passes the pick up isn't enough to sense. So the TCI won't know when to fire.
With the reg/rec unplugged there is no magnetic field to disturb the magnet in the rotor.
As far as room for the magnet, a lot of people just glue one on and there is p[lenty of room.
It worked fine on my 81.
Leo
With the reg/rec plugged in the rotors magnetic field can be stronger than the TCI magnet. The Pickups sense the changing magnetic field as the magnet passes by.
With the reg/rec plugged in this change in the magnetic field as the magnet passes the pick up isn't enough to sense. So the TCI won't know when to fire.
With the reg/rec unplugged there is no magnetic field to disturb the magnet in the rotor.
As far as room for the magnet, a lot of people just glue one on and there is p[lenty of room.
It worked fine on my 81.
Leo
rezsst
XS650 Addict
thanks xsleo
Joesxs650bobjob
XS650 Member
When glueing magnets onto the pickup Do you guys know if they have to be the same size or can they be slightly larger thanks!! Having a hard time finding a replacement tci pickup so going to try this
Look for the rare earth magnet in size 1/4" diameter by 1/16" thick. I had to buy a dozen, it seems, to get one. Amazon or EBay.
I'll add that applying one to an existing magnet embedded rotor is a no brainier as far as polarity. On adding a magnet to a points rotor, do the pickups need to see North or South? Does it matter?
I'll add that applying one to an existing magnet embedded rotor is a no brainier as far as polarity. On adding a magnet to a points rotor, do the pickups need to see North or South? Does it matter?
I got mine from Radio Shack when they still had stores. Their item number is #64-1895 This is a two pack of 3/16 diameter magnets. $2.99.
I think they still have an online store. Won't hurt to check.
Leo
I think they still have an online store. Won't hurt to check.
Leo
