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Jcarter78
11-21-2009, 7:47 PM
Alright. I mounted my Magneto on my 67 T120. 5/16 BTDC, Points barely open .012, right in the middle of the slots for full adjustment. New Plugs gapped .018, new wires, bench tested for spark and it works perfect.

For 2 days now I've been kicking like a mule and It keeps teasing me like it wants to kick over but it doesnt. I adjusted my clutch because the kick felt a little weak and that seemed to help a little but Im still not getting it to start or at least stay running.

Im getting alot of backfiring out of both the exhaust, the carb and compression kickback. I scavenged the archives and cant seem to find any answers. Im hoping someone had a similar problem and theres an angle Im not seeing.

I posted this on JJ too

KT
11-21-2009, 9:39 PM
if it is kicking back from my experiance you are advanced to far retard it a abit see if it wont start

Jcarter78
11-21-2009, 9:56 PM
Yeah its kicking back. Ive advanced it and retarded it. I guess Ill have to try and time it again. I mustve fudged something.

MedusaCycles
11-22-2009, 1:15 AM
Try an .016gap and a ..025 gap on the plugs. you should only have to be advanced 35 degrees on the mag, since it runs full advance all the time. if it kicks back, it's too far advanced, but the gaps and points wil make your life so much better! retard about 3 degrees and try again.

Later,
Medusa Mike

Torch
11-22-2009, 11:23 AM
Try an .016gap and a ..025 gap on the plugs. you should only have to be advanced 35 degrees on the mag, since it runs full advance all the time. if it kicks back, it's too far advanced, but the gaps and points wil make your life so much better! retard about 3 degrees and try again.

Later,
Medusa Mike

Old school mag timing 101-----The mag fires at the very instant the points open, knowing this set the piston at 3/8" before TDC don't move the motor after this, use a piece of cigarette cellophane, put it in between the closed points, rotate the mag body in the opposite direction of the rotor travel while holding on to the cellophane at the very instant the cellophane pulls out of the points lock it down and you are timed at 38 deg. BTC. it is a good idea to check your timing with a strobe gun and a degree wheel.

bhead1968
11-22-2009, 5:10 PM
I got a '66 T120 with a mag...you are most likely 180 deg "off"... those kick backs will break an ankle..

I do it like this>>>>

1. pull plugs & wires
2. unscrew mag cap so you can eye the points AND remove MAG
3. unscrew the crank case plug and the base of your jugs (under the carbs)
4. stick a flat head screw driver in - slooowy kick over (grab the kicker with your hand)
5. "Feel" for the screw driver to "fall into" a notch on the crank..thats your 38 deg BTDC
6. Replace mag and set to the point Juuust opening AND YES in the middle so you can adjust.
7. Plugs back in, plug wires on, crank case plug back in, tighten down mag ..just a bit...
8. KICK - Should fire..then move the mag to were it responds/runs better.

..... thought my carbs were the problem..i never had my mag dialed in from the git... she screams hard now...

Hope this works.....

Torch
11-22-2009, 8:18 PM
unless your timing them a the bottom of the stroke 180 does not make any difference, both pistons go up and down together , the hunt mag will fire both pistons every time the pistons come up to the top whether that piston is on an exhaust stroke on a compression stroke. you can switch the plug wire around and it makes no difference.

Jcarter78
11-23-2009, 2:17 AM
unless your timing them a the bottom of the stroke 180 does not make any difference, both pistons go up and down together , the hunt mag will fire both pistons every time the pistons come up to the top whether that piston is on an exhaust stroke on a compression stroke. you can switch the plug wire around and it makes no difference.

Okay, I thought that maybe that was an issue. I made a rookie mistake. If there is an Exhaust upstroke and a Compression upstroke then I may have timed it on the exhaust upstroke which would explain the back fire. its sparking with the valves open. I dont have that 38 BTDC on my crank jus TDC so Im going by measuring the piston by marking a dowel and getting it at 5/16ths before TDC which is what the hunt directions call for. I may need to get a degree wheel. Im outta town but when I get back ill try this and let you guys know if it worked.

Really appreciate the help.

Torch
11-23-2009, 11:22 AM
Okay, I thought that maybe that was an issue. I made a rookie mistake. If there is an Exhaust upstroke and a Compression upstroke then I may have timed it on the exhaust upstroke which would explain the back fire. its sparking with the valves open. I dont have that 38 BTDC on my crank jus TDC so Im going by measuring the piston by marking a dowel and getting it at 5/16ths before TDC which is what the hunt directions call for. I may need to get a degree wheel. Im outta town but when I get back ill try this and let you guys know if it worked.

Really appreciate the help.
The exhaust and compression stroke are the same thing, don't worry about that.
using a wood dowel is fine just mark it at TDC and then 3/8" up from there. don't use 5/16" that is about 40 degrees advanced, use 3/8" is closer to 38 degrees.
What I am saying is the mag fires all triumphs on the exhaust strokes, that is normal. it fires both cylinders at the same time, one piston is on an exhaust stroke while the other piston is on a compression stroke.
it is more important to get the points opening at the right spot. you can't do that by looking at them you have to do it with a piece of cellophane. it fires at the very instant the points begin to open. it is way too late when you see them open.
Also if you have a timing window on the primary cover you can very easily use that with a timing gun on the factory 38 degree marks to check the setting.

Jcarter78
11-24-2009, 12:23 AM
Okay. so if there is no difference in the stroke then its simply a timing issue. I ordered a degree wheel kit so that will help me accurately hit 38degrees BTDC and I will ignore the Hunt Directions and go with what your telling me. I'll use the cellophane. I need to start Smoking so I can get some.

KT
11-24-2009, 12:57 AM
I'm up to damn near 3 packs a day I can send you plenty

Gepetto
11-24-2009, 1:10 AM
3 packs a day? FUCK DUDE!!!!!

Jcarter78
11-24-2009, 1:42 AM
I'm up to damn near 3 packs a day I can send you plenty

Damn bro. Thats a hefty habit.

KT
11-24-2009, 11:05 AM
I probably smoke 2 and let the 3rd burn on the work bench but yea it is bad I need to quit but fuck never been a quiter no reason to start now ! =)

TRUMPNUT
11-24-2009, 8:15 PM
Something I have seen guys do is time the wrong side of the points cam( i.e. timing should be 32 DEG. BTDC and they end up with 32 deg ATDC ) They will want to start and spit back somtimes a fire ball out the ex. . So take the cover off and give it a kick to see which way it spins ( clockwise ) and make sure that your points are timed on the correct side .

Torch
11-25-2009, 8:24 PM
Something I have seen guys do is time the wrong side of the points cam( i.e. timing should be 32 DEG. BTDC and they end up with 32 deg ATDC ) They will want to start and spit back somtimes a fire ball out the ex. . So take the cover off and give it a kick to see which way it spins ( clockwise ) and make sure that your points are timed on the correct side .
Good point...

charlie500
11-25-2009, 10:23 PM
hey man i just put a hunt mag on a 500 less than a week ago did u get the one with the key built in?

charlie500
11-25-2009, 10:40 PM
when i did mine the first time i titend the the shaft on the cam gear before i set the mag in the center and icoukdnt get it enuff adjustment out of it and u know for every turn on the fly wheel the cam only moves a half turn so u mite still be on the exhaust stroke and not the comprcesion stroke on the cam thats where its matter u could be fireing when the valves are open to exhaust thats the ticket sheck your fly wheel your mark shoult be on the the left side of the center of the bottom u will have to take off your prime cover but if makes it easy to see where your at on your stroke for your motor thats why i like the 500s just take your little cover off and you can see the mark without taking off the hole cover i hope that makes it easyer for you if you want call me and ill help u out ont the phone 9189550209 charlie

Jcarter78
11-26-2009, 8:45 PM
Thanks Charlie. Im gonna work on this the second I get home from my Thanksgiving vacation. I ordered a degree wheel which should be there when I get back to town so that will definitely help me get a more accurate reading for setting it up. I didnt get the one with the key just the plain old no frills model. I'll hit you up for sure if this continues to give me trouble after I try what you guys have told me.

Once again I seriously appreciate the help and input from all of you.

Dustriumph
11-28-2009, 9:22 PM
I went through the same shit on my bike. It's a 66 T-120. Are you getting it set then kicking and it fires then runs for a quick second then dies then nothing but kick, kick, kick? I found that the mag was jumping time. Make sure and set your timing off of the correct side of the points cam as mentioned above then mark the shaft that goes into your exhaust cam and the bearing housing, a sharpie will do, Hook it all back up then kick. It'll fire then die. You'll be 90 degrees out of time at this point. What I found that caused this was the taper shaft on the hunt mag was.020 longer than the corresponding slot on my cam was deep. Put simply it was just too long to tighten down enough to keep it from slipping. I called hunt and told them what I had found. They basically told me to get fucked. I didn't have the gear to make that shaft the right lenght, and I didn't want to run those guys stuff since they were asses to me, so I sold the mag and am just running points and a capacitor.

Torch
11-28-2009, 10:22 PM
I went through the same shit on my bike. It's a 66 T-120. Are you getting it set then kicking and it fires then runs for a quick second then dies then nothing but kick, kick, kick? I found that the mag was jumping time. Make sure and set your timing off of the correct side of the points cam as mentioned above then mark the shaft that goes into your exhaust cam and the bearing housing, a sharpie will do, Hook it all back up then kick. It'll fire then die. You'll be 90 degrees out of time at this point. What I found that caused this was the taper shaft on the hunt mag was.020 longer than the corresponding slot on my cam was deep. Put simply it was just too long to tighten down enough to keep it from slipping. I called hunt and told them what I had found. They basically told me to get fucked. I didn't have the gear to make that shaft the right lenght, and I didn't want to run those guys stuff since they were asses to me, so I sold the mag and am just running points and a capacitor.

we install a couple of Hunt mags per month on bikes at our shop and I have see one bike that had a wallowed out cam that made it so the mag would not stay in time, but that wasn't the mags fault.
most of the time you have to shorten the 1/4" bolt the holds the tapered hex drive into the cam. and you have to punch out the locating pin inside the cam taper or it wont seat the hex drive.

Dustriumph
11-29-2009, 12:01 AM
Brand new mega cycle cams. No walloring yet and no set pin. And I checked the 1/4 inch bolt because I figured that would be it, it wasn't.
I'm not saying it was or was not hunts fault. I'm saying they were assholes to me when I told them what I had going on and asked for help. I called them and got a load of attitude when I was asking them for help on their product. Which I purchased new from them.
I'm not a professional mechanic but I'm not a totally helpless moron either. The fellow that was helping me is a professional and has been for thirty years. He's installed these and ARD's as well. We were both stumped and that's why I found the taper shaft was too long. We had exhausted all of the other possibilities that either of us could think of.
Just my experience and my two cents on Joe Hunt.

Torch
11-29-2009, 7:24 AM
Brand new mega cycle cams. No walloring yet and no set pin. And I checked the 1/4 inch bolt because I figured that would be it, it wasn't.
I'm not saying it was or was not hunts fault. I'm saying they were assholes to me when I told them what I had going on and asked for help. I called them and got a load of attitude when I was asking them for help on their product. Which I purchased new from them.
I'm not a professional mechanic but I'm not a totally helpless moron either. The fellow that was helping me is a professional and has been for thirty years. He's installed these and ARD's as well. We were both stumped and that's why I found the taper shaft was too long. We had exhausted all of the other possibilities that either of us could think of.
Just my experience and my two cents on Joe Hunt.

Yea, it sounds like you had something wrong with it hunt taper drive,the points taper fit right in. I would have shipped it back to hunt and told them to get their shit together.

bhead1968
11-30-2009, 11:40 AM
"Shorten the bolt, I had to... mine wasn't obviously loose, but every time I killed the bike after firing it up for the first time, it jumped timing cause the shaft would slip when the motor stopped. took a 1/4 inch off, no more worries..."

This is the quote that helped me. havent looked back since.... wild that you got so frustrated and got rid of the mag just because of the bolt issue?.. to each his own... sucks about the Customer Service to got from hunt..i never had an issue, then again i got mine thru lowbrow.. tyler was very helpful and even called and delt with the hunt folks for me...

good luck and ride safe.

Jcarter78
11-30-2009, 10:25 PM
Yep. Same here, the bolt was too long. Cut it with a hacksaw blade, screwed it in and it tightened right up. I went through a whole litany of shit before I figured this out. Bought a degree wheel, shortened the tapered hex drive on the lathe, got new spark plug wires, etc. Live and learn I guess.

She runs better than ever now that I got the mag all sorted out. I recommend one.

Thanks again guys and thanks Charlie for dropping some knowledge on me over the phone.

Jcarter78
11-30-2009, 10:25 PM
Yep. Same here, the bolt was too long. Cut it with a hacksaw blade, screwed it in and it tightened right up. I went through a whole litany of shit before I figured this out. Bought a degree wheel, shortened the tapered hex drive on the lathe, got new spark plug wires, etc. Live and learn I guess.

She runs better than ever now that I got the mag all sorted out. I recommend one.

Thanks again guys and thanks Charlie for dropping some knowledge on me over the phone.