correct accell or dyna coils

[Axel]

http://www.xs11.com/forum/showthread...=&threadid=583

[TopCatGr58]

Shappers,

I'm sure there is a thread that tells of what size resistor you can get and put IN LINE between the coils and the TCI's R/W wire that powers the coils. You should also be able to go to your local auto store and pick up one as well. It should be 1.5 ohms. You really don't want to use the lower ohm coils without the resistor because with the reduced resistance, they can draw more power/amperage thru the TCI that is providing the power to the coils and could damage it(TCI)??

I realize that the article says that coils are not really voltage specific, but since the Dyna Coils are rated at 6 volts, with 12 volts of electrical pressure on the line, and less resistance present...only 1.5 ohms of the coil vs. the extra 1.5 ohms of the resistor in line...means that more amperage will be pushed thru the coils, and this is what could cause them to get burned up!?

So....running the 1.5 ohm coils without the ballast resistor could put both the coils and the TCI at risk!

But it's your money, so if you want to do this experiment, the best of luck to you!
T.C.

[Pat Kelly]

The 12v circut is probably linked to the starter.
In auto (old ones) ignitions the ballast resistor was bypassed when the starter was engaged to send full 12v to the points. After the engine started (key returned to the run position) the 12v was routed to the ballast resistor to drop the voltage to 8v or so. This helped the points last longer.
On the XS it is probably to ease the load to the TCI.

[Shappers]

Ok TC, I don't want to risk the coils as they flew all the way from sunny Florida to Finland..

I will source some nice 1.5 Ohm resisters and go with those...

Thanks!

[conquest87tsi]

Coils

I am a little confused on 1.5ohm, or 3 ohm coils selection. I have a 1979 XS1100 special. So from what I've read, it requires the 1.5ohm coils. Is this correct?

You guys have been using the term "earlier" and "later" bikes. When was this distict change exactly? Or is the difference between standards and specials?

Is the ballast resistor the 3" stamped steel piece near the coils? If so my 1980 Special parts bike has one as well, so I'm not sure when the change was made.

So is it correct that I could just bypass this resistor and go with 3ohm coils?

[natemoen]

'81 bikes were the first to use the 3 ohm coils. And yes, the stamped steel thing is the resistor.

All the XS and XJ bikes use a 3 ohm ignition system. It is just that the pre '81 bikes use a 1.5 ohm coil and a 1.5 ohm resistor to achieve the needed 3 ohms. So when people upgrade to new coils they use 3 ohm coils and eliminate the ballast resistor.

[DGXSER]

Yep, what Nate said!! 81 model year was the factory change. Does not mean some PO did not make a swap on you and you have 3 ohm coils and no Ballast Resistor already though.

[conquest87tsi]

Coily

Well I know the parts bike still had it, pretty confidant I saw one on my rider. I haven't had a noticable problem with the coils yet, put I did have a boot come off and there were not too many strands contacting it on #1. So I am thinking it won't be a bad idea to do over the winter. Not sure I want to fix something that isn't broken judging by all the horror stories with replacement coils.

What is the common life of the stock coils? I have 15,000 on mine. Also how long are people seeming to get out of the 3ohm Dynas?

[TopCatGr58]

Hey there Conquest,

Well, Greg(BA80) will tell you his are 32 years old and still working fine! As was posted in the thread about the MikesXS monster Green Coils, there are no moving parts, and so in general QUALITY made coils should work for decades. The MikesXS coils we have found are NOT quality made, and so they tend to burn up internally. The same can happen to the OEM 1.5 ohm coils IF they are run without the ballast resistor, as well as fry the TCI.

But, the older 1.5 ohm coils are only getting ~9 volts when running, possibly even less due to corrosion and voltage drop along the harness, so..they are not necessarily making a very strong spark. Their KV rating is around 15kV. Also the old coils plug wires and insulation also breaks down allowing shorting, the plug caps also can corrode internally, develop way too much resistance and such, the wires are a real PITA to replace on the OEM coils!

The Dynas are rated at 35kV, over twice as strong, and are designed to run on 12 volts all the time, so bypassing the BR permits that, and using the 3 ohm style keeps the current draw from/thru the TCI the same as the OEM setup, so the TCI doesn't get fried. The stronger spark makes both starting and running easier and stronger, with possibly more thorough combustion which should provide a little boost to mileage, if at least performance.

The Dynas come with a 1 year warranty, the mikesXS ones have NO warranty, and we're finding that they are ALL chinese junk, and so are no longer recommending any of them!

T.C.

[clashpistol]

**Note on dyna coils**

I bought the same coils after reading Pat's excellent write-up.

Then I realized later that I have a late bike which doesn't have a ballast resister fitted so the coils are not correct for my application

Just check if you have one or not before blowing $100

My SF is a 79'. I have had running issues for 2 years and recently installed the red 1.5 ohm coils. Here everyone says green coils, green 3.0 ohm coils etc.
The early models had 1.5 ohm coils and the ballast resistor. The ones on my bike were 3.0 and did not realize it until until checking Clymer manual and ohming out coils prior to ordering. It does have the ballast resistor.

I have had the carbs off over 20 times trying to rectify running issues and after a few times got rid of the air box and installed individual filters. I kept on having a cold cylinder 3 whatever I did. I switched wires and the problem followed to that cylinder. I checked my pick up coils early on and had no issues, My carbs were thoroughly cleaned a few occasions floats set and checked over and over and genuine mikuni jets were installed. Carbs have been synched upon every change so it has been thoroughly frustrating to say the least. I am in the process of pulling carbs out again now to install 142.5 mains. I previously installed them and still had running issues.
It now runs better than ever and hopefully with larger jets will be the ticket.

I went for a ride last night and there are street lights out to edge of out town and cars were on the road to follow. When I got on dark open road I noticed that the headlight was dim and high beam did not work. There is no fluctuation or dimming of low beam when running and accelerating/ decal. I have 12 volts at bulb for low beam but none high. Is this perhaps related to coil install? I will be chasing gremlins and plugs after main jet install. All my electrical is diaelectric greased, disassembled and clean and operated perfect before coils.

Thanks,

Jeff

[natemoen]

Nope, the ignition coils will only affect the ignition circuit. Your headlight issue is elsewhere in the system. Check the bulb first though....

[fredintoon]

Ohm, Ohm on the range

I got my XS11SG in pretty sad shape but it did have green aftermarket coils on it.
Having no comparison except that the XS11 had way more power than my XS650, I thought it ran OK.
Some years later I read posts on this list about 1.5 Ohm coils + resistor vs 3 Ohm coils and no resistor.
So I checked my bike.
The dreaded PO had swapped in 3 Ohm coils and kept the resistor.
Pulled the resistor wires and plugged their terminals together.
Bike ran OK before but runs far better now.

[Axel]

funny

Fred , you are too much !!!

[Rmcguire]

Hi all...I am new to Yamaha. Always had Triumphs and now Victory but I did pick up a 1979 XS100 standard and am still confused even after reading all the posts. I purchased my coils from DYNOMAN Performance after posing the following question:
I have a 1979 Yamaha XS1100 standard and would like to know which coils and wires would be the best fit.

Thanks in advance for your help,

Rick McGuire

The response I received was this:

Hello Rick,

The (3 ohm) DC1-1 coils and DW200 wires would be the correct parts for your XS1100. You can see them here: http://www.dynomanperformance.com/ig...dynacoils.html

You can order through our shopping cart if you wish or just let us know what you need and we will be happy to send you a PayPal invoice that you can pay with any major credit card.

Thanks very much for looking and have a great week!

I hope this helps someone.

Rick

[DiverRay]

Welcome to the site! Yes, you can use the 3 Ohm coils on the '79. The ONLY thing you should do is bypass the ballast resistor on the left side of the frame, under the tank. All you need to do is unplug the resistor, and plug the two wires from the harness into each other. Just make SURE they cannot short to anything! Wrap with tape works, so does cut and splice with a marine grade crimp connection.