xj550 spark plug wire caps

i read in chacal's parts list that the caps for 2&3 are different from 1&4. does it make a difference if they're all the same? im at work right now so i cant look at the bike, and im trying to find where i can get them on the way home. does anybody have the NGK part numbers for them? i saw on one thread that its LB05F which i guess is the short 90 degree cap. is it ok to use 4 of those or would i run into problems?

 

2&3 are longer, you can use the short ones, but it don't look so good.
Don't know the NGK part# but the Yam' #s are:
1&4....... 55x-82370-00-00
2&3....... 1y-82370-20-00

 

ill just get em from chacal and make my life easier.

 

The 550's, like the bigger bikes, are different between the inner and outer pairs.

The 550s also use a different style and resistance cap than the bigger bikes.



The outer cap is on the left; the one on the right is the inner cap.

 

thanks for the pic, i took a look yesterday and did realize that they're different, i can't believe after changing out the plugs about 3 times i never noticed that. it turned out only the outer 2 caps 1&4 were wasted, the inside 2 were perfect. i called the local shop to see if they had them in stock and they said they didnt. i went in today anyways and they had them in stock and they were only like 2.50. go figure. put the new caps on tonight, bike started easily first time no faffing and those caps dont shock me anymore! it was misfiring alot on the ride back from the shop yesterday and now its smoooth.

i have to say, thanks so much to everybody on this forum for helping me get my bike sexy again. ive had it for 4 months now, and im finally going to register it at the dmv tomorrow.

here's a picture of the old caps, im surprised the bike was even able to start with these things on.

 

I can't quite figure out how they get broken like that either but it sure is common.

You would be AMAZED at how bashed up they can get and still work.
One of the caps on the ratty 650 I picked up was broken in two and I glued it back together and built it up with the adhesive so it would at least stay on. It worked. (Since been replaced.)

Are your new caps exact replacements; ie; resistor caps with 10K Ohms resistance, or just "booties?"

If they're not resistor caps, you might want to get a set from Len anyway. I'm not sure what the long-term effects of running non-resistor caps would be.

 

i got the resistor caps from chacal and installed them today and also put in a new blade type fuse box. man, what a difference. bike screams to life and runs much smoother.

i dont know if it was because of the non resistor plug caps but the bike used to be really hesitant basically all through the tach unless i really hammered on the gas then it would wake up and ride smoothly. but that problem is gone now, so ill make sure only to use the resistor caps from now on to be sure.

 

Hey guys I just read this and it seems that I may have a problem with these caps. My xj550j started missing and seems to be runing on 3 cyl's lately. I check the plugs and they are all gray/tan and dry. I check the coil resistance with a meter and all leads on both coils seem the same. Do you guy think I could have a cap problem? I pulled the caps off one at a time while runinng, you can tell how much worse the bike ran each time I pulled a cap until I got to the #2 plug, I can pull it and the engin runs no different. Should I try to buy new caps?

drl82xj

 

Don't quote me, but I THINK that 2 and 3 fire at the same time. Or at least very close to each other. If it was me, I'd switch them and see if 3 goes dead.
Only for a quick test anyway.

 

Twist each cap off it's plug wire (one at a time) and measure the resistance through the cap.......it should be 10K (10,000) ohms +/1 10% on the 550's...........if any are out of spec, they need to be replaced. Also, it doesn't hurt to clips off about 1/4" of the plug wire end before you re-install the caps onto the wires.

But also check the secondary resistance of the coils (both plug caps OFF), they should be 11K +/- 10%.

 

How long do the spark plug wires last? Just curious since they can't be replaced without also changing the coil. (I think)

 

Well, they last "as long as they last"...........as long as the resistance thru the entire coils is within spec, you can assume that the wires are still good (assuming no breaks in teh insulation). If the coils is out of spec, then you might want to try cutting off the plug wires and re-measure the resistance; if it drops down to spec, then the plug wires were the problem; if not, then the coil is bad.

Of course, if you cut off the plug wires from the coil, leave about a 1/2" stub of plug wire where it exits the coil body, so if the coil is now "in spec", you'll have a bit of plug wire left to use as a splicing point for installing new plug wires.

 

The correct answer is:

"As long as a string."

chacal is absolutely right; all I can add is that they generally have help failing (that "ham-fisted pink monkey" thing again.)

 

chacal, you said above about cutting back the plug wire to test and leave a 1/2 inch for new wires. I was told you can't replace the plug wires, is there a kit or do you just crimp on new wires if you coil is still good? And if this is possible is there a preferred type of plug wire to use? And if you can put new wires on would the crimped connection add to the resistance on capacitance?

thanks
drl82xj

 

Well hey guys, the ideas above really sparked my interest (excuse the pun) so I just ran out to the garage and pulled off the spark plug caps. I found cyl 1 at 11K, cyl 2 at 168K, cyl 3 at 30K and finally cyl 4 at 11K, and these all should be 10K right? I also tested the coil without the caps and the secondary side Omms out even on all four wires a around 230 oms. So I guess this is a no-brainer right?

So my next question would be, were to get them. Bike Bandit wants 23-24 bucks per cap, do any of you know who sells these cheaper?

drl83xj

 

Drl82.......you can replace a PORTION of the plug wires----the length that is external to the coil body----with the use of an in-line plug wire splicer that we offer.......zero resistance! And you can actually do "coil surgery", but it involves sawing open the coil cases where the plug wires enter, replacing he entire wire unit, and then recovering the col body with some type of silicone or epoxy material........a bit more involved.

We do offer both original and replacement plug caps for your bike, just drop us a PM or an e-mail and let me know which ones you need......from your readings above, caps #2 and #3 need replacing, but you should replace buy all four.

We also have original style 0-ohm plug wires and terminals available.

The coil resistance specs are as follows:

For all models except XJ700's and XJ900RK:

Primary (input): 2.5 ohms +/- 10%
= 2.25 ohms - 2.75 ohms

Secondary (output): 11K ohms +/- 20%
= 8,800 ohms - 13,200 ohms without the caps installed on the wires.