Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Vintage Royal Enfield => Topic started by: rvcycleguy on May 25, 2013, 12:52:05 am

Title: 12v coil
Post by: rvcycleguy on May 25, 2013, 12:52:05 am
Is there a USA source for a 12v coil? for a vintage RE Bullet? 
Title: Re: 12v coil
Post by: gunnerasch on May 25, 2013, 02:14:25 am
any normal 12vt automotive coil will work. You simply need to add a bigger coil bracket
Oh...the English ones are available on Ebay

Title: Re: 12v coil
Post by: baird4444 on May 25, 2013, 02:41:06 am
The Bosch Blue coil has been a hop up replacement for a while just as it was for hopping up a VW
back in the 60's and 70's. There is also an easy replacement from NAPA. Below is from my files....
                - Mike
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
MIKE,
I'VE SEEN YOU HAVE BEEN TALKING ABOUT THE BOSCH BLUE COIL. JUST RECEIVED MINE TODAY. HERE IS SOME INFORMATION I HAVE FOR YOU.
BOSCH BLUE COIL PURCHASE:
AFTER MUCH RESEARCH http://www.ratwell.com/technical/BlueCoil.html & http://www.1800vw.bizhosting.com/coilhdbblue.htm I ORDERED A COIL FOR MY BULLET FROM VICTOR COMP. PRODUCTS BECAUSE HE HAD THE CORRECT COIL FOR THE BEST PRICE $26.95. WHEN I WAS AT MID OHIO VINTAGE MOTORCYCLE DAYS DRS CYCLE HAD THE BOSCH COIL FOR SALE BUT IT WASN’T THE "GOOD" COIL ACCORDING THE ABOVE WEB SITES. THIS IS WHAT DRS CYCLE SAYS ABOUT THE BOSCH BLUE COIL (Bosch blue coil ,this item will single handedly increase performance by bolstering the ignition system , this will increase the voltage from 35,000 to 50,000 volts . This will improve the combustion process and is a better quality coil! $45.95.
12/27/2004
TERRY...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
http://www.1800vw.bizhosting.com/coilhdbblue.htm

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Info from a NAPA tractor coil that works…
Hello all!
The NAPA Part number is IC12SB. Check to make sure you get the correct
resistor/non-resistor model.
Ask, look at the box, then check the coil before you walk out :)
It runs about $14.99 US plus tax
Mine works fine, but for the life of me I can remember if it is resistor
or non, but I /think/ it is non.
Course, it works so I never have to look at the darned thing, but I
still keep my little tiny original one in the side can just in case.

Have fun!
-=Bryian=-
(4 inches of snow yesterday morning-60 degrees today and sunny- Got to
/love/ Ohio weather!)

--
Nothing real can defeat us. Nothing unreal exists.
-B. Banzai


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The good Bosch blue coil will have the bracket attached and a circular label on it. The cheap ones are a different shade of blue and do not have the bracket attached and have a square label on them. They both use the exact same part number, so when ordering you need to specify THE GOOD ONE or the one with the bracket ATTACHED. Many budget vendors (full page rag ads) pawn the cheap ones off as the good BLUE coils, since they are both blue
 
Title: Re: 12v coil
Post by: rvcycleguy on May 25, 2013, 02:43:01 am
Thanks guys. 
Title: Re: 12v coil
Post by: rotorwrench on May 25, 2013, 03:22:45 pm
All the small coils are for motorcycles. Standard ignition most generally use a 1.5 Ohm primary. The electronic coils are generally less for a reason. you will have to find out which system you have to get the correct coil. You might call up to Fairbault & ask them how to ID the set up you have unless you have a local royal enfield dealer to ask.  If the stuff on the bike is lucas, then it's the old standard ignition with points & condenser & distributor otherwise known as a battery ignition.

The wrong coil can do damage to an electronic control box if that's what it has.
Title: Re: 12v coil
Post by: rvcycleguy on May 25, 2013, 04:59:17 pm
Thanks rotorwrench. I located the NAPA part # IC12SB this morning.  Much bigger and does not come with a bracket.  The old coil and bracket will not accommodate.  I do not see a resister mounted anywhere so, non resistor looks like what I need. 
Title: Re: 12v coil
Post by: rvcycleguy on May 25, 2013, 06:38:42 pm
Ordered the IC12 and ICB10 Bracket and ICR13 resistor. Be in later today.
Title: Re: 12v coil
Post by: rvcycleguy on May 31, 2013, 12:38:41 am
Put a new 12v coil on it.  Used the NAPA part number offered here by a forum member.  Back on the road again.  Thank guys.  Kick starts much easier now.  The one that came off it was an old Lucas brand.  Had to use a new bracket that was ordered with the NAPA coil.  No resistor. 
Title: Re: 12v coil
Post by: High On Octane on May 31, 2013, 04:14:16 am
Glad to hear you're back on the road.   :)

Scottie
Title: Re: 12v coil
Post by: rvcycleguy on June 03, 2013, 02:51:29 pm
Bike starts easily and idles well.  But, it seems to have a misfire under a load?  At low speed, it sounds fine but when I roll on the throttle, it misfires repeatedly.  Rode the bike to my workplace on Friday and the trip there is about 10-15 miles.  Has to ride with the choke ON the whole way there.  Then in the afternoon ride home, it was misfiring and almost did not get home without stalling it.  Coughing, sputtering, etc. 

I start it up yesterday after sitting for 2 days and starts easy, roll on throttle in garage and seems fine.  Again, its seeems though under a load of that the problem arises?

is the new coil too hot and burning the points?  Did not use a resistor.  Do I need on? 

thanks,

rv 
Title: Re: 12v coil
Post by: ERC on June 03, 2013, 04:10:33 pm
If your using the choke to keep it going I would think your carb needs attention.   ERC
Title: Re: 12v coil
Post by: rvcycleguy on June 03, 2013, 04:24:35 pm
yes, the carb was also something I was thinking about.  I've not added gas since I bought it a month or so ago.  ODO is in KM and I've not yet calculated how far the tank will go.  It may be down at the bottom and picking up some trash?   

thanks. 
Title: Re: 12v coil
Post by: Arizoni on June 04, 2013, 01:21:51 am
If you want an exact conversion from km to miles, divide the number of km by .621.
If you want an approximate mile number divide the km by .6 .

Your bullet should be able to give you over 240 km (150 miles) on a tank of gas.
Title: Re: 12v coil
Post by: rvcycleguy on June 04, 2013, 02:48:33 pm
Thanks Arizoni.  My fuel tank has been modified and enlarged.  From my understanding from the seller, it has an addtional 2 gallons. 
Title: Re: 12v coil
Post by: rvcycleguy on June 07, 2013, 06:35:41 pm
Update on the 56. 

I road it to work last Friday after putting in the new coil   Cranked up fine and was going good.  Then started to miss fire when I rolled on the throttle.  Got to work and parked it.  On the way home it got worse and almost did not make it home. 

Took it to a tech who specilizes in vintage and he checked it out. He felt that the old coil was covering up a dirty carb issue?  May have been there all along but the old and weak coil was part of the problem.  I had to run with the choke on most days.  He cleaned the carb and put a larger jet in as well.  Picked it up at lunch today and he demonstrated how nice it idles and how I don't need the choke.  Does need it to kick start but as soon as it fires up, he flicked it off and the bike ran very good.   I'm not wanting to rely on tech service but the bike is old and new to me, so for the first few weeks, I wanted to have an expert check it out. 
Title: Re: 12v coil
Post by: rvcycleguy on June 08, 2013, 12:52:09 pm
Still have issues...  Rode it last evening and kick starts first time.  Excellent.  Idles well.  First gear, 2nd gear all seems well.  3rd into 4th, as long as I'm rolling on throttle, seems fine. Good acceleration.  Wen I roll off and maintain speed, it miss fires.  The farther I ride it, the worse it gets?  Like choke is stuck.  But it's off and I can move the linkage up and down.  It's sticky, like it needs some cleaner there but it does appear to shut off.  And when I apply the choke, it really falls off.  Shut choke off, and it idles well, takes off well in low gears, but after that it miss fires.  At some point, it hard to explain miss fires or engine missing due to the speed I'm carrying and the wind noise does not allow me to hear the engine and muffler to know exactly the miss fire.  But it's definitely jerking and sputtering.  Back down in gears and seems fine again.  Any suggestions.  Previous owner asked me last night, was I aware of the spark plug check after a carb clean? 
Title: Re: 12v coil
Post by: GreenMachine on June 08, 2013, 04:26:19 pm
Is the bike utilizing points/condenser and if so have you checked the gap when the piston is right at BTDC ? 
Assuming u have done that procedure and it check out correctly , you might as well check the valve train clearances. Even before you try any of this, if your riding with the throttle on (say 4th gear) and you flip the choke/en- richer tab, do you notice any difference with it up or down? 
Title: Re: 12v coil
Post by: rvcycleguy on June 08, 2013, 04:38:18 pm
It is utilizing point and condensor.  i will check the gap.  yes, the engine performance falls off considerably when I push down on the choke lever while riding. 
Title: Re: 12v coil
Post by: ERC on June 08, 2013, 05:45:53 pm
The choke should be completely open when warmed up and riding. If it falters when closed when warm then that is normal. If it makes bike run better closing when warm then you most likely have carb fuel delivery problems, clogged jets, dirt, etc.   ERC
Title: Re: 12v coil
Post by: rvcycleguy on June 08, 2013, 06:07:06 pm
Just had the carb rejetted and cleaned two days ago by a well experienced shop here for vintage bikes.  Problem existed before I took it in there!  Some of the issues were fixed like hard start, no idle.  Tech told me he rode the bike several times around the shop neighborhood.  I also rode the bike after picking it up and it started on first kick, rode well in low gears and then decided to ride to a buddies house 20 minutes away and it performance fell off every mile. 
Title: Re: 12v coil
Post by: GreenMachine on June 08, 2013, 06:41:35 pm
I have u verified the size of your pilot jet...Being a older bike, I would think it has a after market exhaust...Obviously your're starting the bike (even if its cold natured) and riding around...I would shut off the gas petcock and pull off the carb bowel carefully and pull out the pilot and main jet to check if they are blocked and find out what size u have....Might just be u need a bit larger for both....
Title: Re: 12v coil
Post by: rvcycleguy on June 08, 2013, 07:05:48 pm
My tech told me yesterday he took out a 25 and put in a 30?  Hope these numbers help?  As your understanding, the bike starts right up, idles and rolls on throttle very well in neutral.  Then as I ride away, its good up through 1-2  gears and then in 3rd and 4th, when I'm not rolling on anymore throttle, it begins to miss fire.  Last night, it seemed to me that if I rolled on throttle in 3rd , it was steady acceleration, then when I put it in 4th, it fell way off and if I rolled on more throttle it would clear out and smooth, but If I rolled off, it then miss fired
Title: Re: 12v coil
Post by: rvcycleguy on June 08, 2013, 07:12:06 pm
I appreciate everyones comments this morning.  I'm somewhat mechanically inclined but its been a few decades since I messed with points, condenser, coil, carb, etc.  I rebuilt and maintained a 69 MGB for years so I'm accustomed to Lucas but lost most of that hands-on long ago.  These bikes seem so simple... how hard could it be? right.  My non British everyday bike with EFI and ECU is maintence free.  I knew what I was asking for when i bought the bike a few weeks ago.  Beautifully restored and updated and starts everytime.  just won't run smoothly on the road?
Title: Re: 12v coil
Post by: ERC on June 08, 2013, 10:58:09 pm
Did you try something simple like changing the spark plugs and checking the gap? About .020"  ERC
Title: Re: 12v coil
Post by: rotorwrench on June 09, 2013, 12:12:39 am
Condensers are hit and miss in this day and age. You can buy a brand new one and it won't meet the capacity check and many times they aren't proper micro farad spec or they leak like a sieve. I usually buy 2 or 3 at  time to insure I get at least one good one. Old Lucas parts were wax paper wound and they are crap so stay away from NOS Lucas stuff.

Also check your fuel supply and make sure you have good flow to the carb.
Title: Re: 12v coil
Post by: rvcycleguy on June 09, 2013, 02:17:52 am
Allow me to update and also review the thread. 

Went on a nice 2 hour ride with a group.  All went well outbound.  No mis firing, no stutter, solid cruise.  On the way back, bike quit running.  No fire at all.  Got it back home and took it to a tech garage that I trust.  He tested the coil and no fire.  Ordered a new one and installed it.  Fired right up.  Brought it home and rode it to work on Friday of that week.  Mis fired many times and almost did not get home.  Had to run it with choke on.  Took it to another shop that handles vintage bikes.  He cleaned and rejected the Mikuni carb from 25 to 30.  Fires right up, good idle and no choke.  I put a new spark plug in today and rode it again.  Still same symptoms.  Mis fire under load.  1st gear seems ok. 2nd gear seems ok.  3rd and 4th just stutters all over itself.  Gets worse the longer I ride it.  If I put the choke on while riding its worse. Will actually die if I leave it on too long.  Starts right back up, first kick.  No choke.  Idles fine again.  Take off and it stumbles under load. 

I've checked the coil wire on both ends for tight connection. Could be the condenser?  Breaking down under load?  Thanks,  RV
Title: Re: 12v coil
Post by: ERC on June 09, 2013, 01:30:23 pm
Coil and condenser will both breakdown when hot, OK when cold. Very hard to test by the time you get them hooked up to test they're cooled down and can test ok.  ERC
Title: Re: 12v coil
Post by: rvcycleguy on June 09, 2013, 01:56:17 pm
Thanks ERC.  Is there a local store bought condenser available for the old style set up?  I found the coil at NAPA based on a post here with the part number equivilant.  Is there a compatible condenser? 
Title: Re: 12v coil
Post by: rvcycleguy on June 09, 2013, 04:06:06 pm
Yes, it does appear to stutter, mis fire after its warmed up.  Have ridden it several times today and when cold, it's strong performance.  After a few minutes going up to 100km and back down several times, it does begin to mis fire more and more the longer I ride it. 
Title: Re: 12v coil
Post by: ERC on June 09, 2013, 04:09:41 pm
You asked about 12V coil is your ignition system 12V? The bike you say is 1955 all of them were 6V. If it was changed to 12V it could be your condenser is 6V and breaks down with 12V. Is the distributor original. If original the # is LU/491329. But that's a 6V one. I would think if you need a 12V one a later Bullet one may fit. ERC
Title: Re: 12v coil
Post by: GreenMachine on June 09, 2013, 04:14:07 pm
Yes indeed caps are affected by heat and break down. I was under the impression that if your cap is bad that you would noticed excessive pitting of the points...When the bike came home dead from your 2 hour ride, did u noticed what the battery voltage was?  Have you taken off the ground wires from the battery and located the other ends to see if they are indeed grounded to bare metal on the chassis (Especially the main wire that goes behind the battery box?  A intermittent high resistance ground can cause strange issues like this too..A dremel tool is helpful for removing rusty contact points....GM
Title: Re: 12v coil
Post by: rvcycleguy on June 09, 2013, 06:03:28 pm
I'm of the mind that the new 12v coil is still the source of my mis fire.  Why?  because it was not running rough before the coil went out.  It ran smooth and easy for 100 miles.  Now it fires up easily but mis fires when it warms up.  I've thought throughout this  process that the coil may be too hot?  Too much for the system.  The coil I took off it is Lucas and has 12v on the label.  It's a smaller scale diameter and height then the new one from NAPA.  Had to find coil bracket to fit the new one.  The NAPA coil has a label on it that indicates requires a resistor.  I asked both my techs if it needs one, both said no.  It appears to have the original distributer.  But, the electrics have been updated from 6v to 12v.  The battery is 12v.  I took it out of the box today and made sure all connections were tight.  I inspected the coil wire to the coil end and appeared snug fit into the top of the coil.  The spark plug end is tight.  It's the type that has the threaded push on type end that mirrors the plug connector is also push on threaded.   The seller rode it daily to work, although not that far.  I've communicated with him several times to ask about this issue and he is also stumped.  Again, running well before the coil went out. 
Title: Re: 12v coil
Post by: Arizoni on June 09, 2013, 11:25:20 pm
I don't know about your coil but there are some automotive coils for 12 volt systems that are made to run on 12 volts during starting and at lower voltage after the engine is started.

To accomplish this on the cars, a wire is run from a terminal on the starter motor solenoid to the coil.  When the starter motor is activated, a full 12 volts (minus the voltage drop the battery has when its being called on to provide a lot of power) is sent to the coil.

Another 12 volt wire in the ignition circuit goes from the key to a ballast resister.  A wire from the ballast resister goes to the coil.  This provides a lower voltage for the coil while the engine is running.

If you have this type of 12 volt coil and you are running it without the ballast resister that could overheat it.

To see if overheating is the problem have you stopped the bike and touched the outside of the coil?  If it was overheated I would think it would be very hot.
Title: Re: 12v coil
Post by: ERC on June 10, 2013, 12:10:26 am
Arizoni is correct the ballast resistor is used to reduce the voltage to the coil to about 9v for running it also helps the points last longer. On older cars they used a circuit to bypass the resistor so it received 12v giving a hotter spark for starting. Could very well be you put the wrong coil on there resulting in your problem. Look up the # on your coil on the computer and see if it requires a resistor. If it does try one that runs on 12v all the time and try it.  ERC
Title: Re: 12v coil
Post by: rvcycleguy on June 10, 2013, 12:29:00 am
Thanks ERC and Arizoni.  The NAPA coil part number was offered here on the forum in this post back on page 1 from Baird4444.  I have a NAPA resistor that is compatible with the new coil.  It's a ceramic external type that mounts to the same area as a coil.  As a newbie on this, where does it tie into the wiring?  One side from the distributer and the other side is the battery ?
Title: Re: 12v coil
Post by: Ice on June 10, 2013, 12:49:03 am
Not all blue coils are the same. Some have internal ballast resistors and others do not.

Here's a link to an informative article on the subject.

http://www.ratwell.com/technical/BlueCoil.html
Title: Re: 12v coil
Post by: ERC on June 10, 2013, 12:50:24 am
Hook it to the positive side of the coil. That's the wire that will go to the ignition switch. The negative side goes to the distributor. Just hook a wire to one side and the wire you took off the coil to the other side.    ERC
Title: Re: 12v coil
Post by: rvcycleguy on June 10, 2013, 12:59:13 am
Thanks. 
Title: Re: 12v coil
Post by: rvcycleguy on June 10, 2013, 05:45:15 pm
Well, I may be back on the road.  I found a place here called BAP GEON.  It's a physical and online European parts store.  I went over there this morning and bought another coil thinking I have to eliminate what was put on since it quit running on me a few weeks ago.  Bosch Blue ( Brazil made).  Swapped out the new NAPA with the Bosch and started it up.  As you know, idle and kick start was good with the NAPA coil.    I rode it for 30 minutes, same time period for the stutter and misfire to reveal itself with the NAPA coil.  Only this time, no misfire.  Rode it, rode it and rode it some more.  And no misfire.  Went out to the highway feeder road and rode it some more.  No misfire.  I hope this continues....  Thanks for your assistance. I'll be back!!!!
Title: Re: 12v coil
Post by: High On Octane on June 10, 2013, 05:52:18 pm
AWESOME!  That's great news!  Glad you're back up and running.

Scottie
Title: Re: 12v coil
Post by: rvcycleguy on June 18, 2013, 07:07:38 pm
Replaced the spark plug after locating the NGK type for it.  Bike has not been run in a few days and went out to the garage last night and put the new spark plug in.  Kicked it one time and it started right up. Yea...  Rode it around the neighborhood and its peppy and strong.  The part I'm still trying to get used to is the lack of windshield.  I've ridden bikes with a shield since the late 80's, so its strange and noisy to ride without one even on this little bike.  Can't imagine putting on a wind deflector of any type based on the looks and options I may have.  I normally ride a big cruiser and wear a FF Modular, but with the vintage RE, I'm wearing a 1/2 helmet with wrap around shades.  I'm going to try one of my other helmets that is a 1/2 style with neck curtain to cover the ears.  The wind noise and buffeting is somewhat annoying and keeps me from riding very far.