busted sparkplug boot

I was replacing the boot resistors with screws for a hotter spark and shattered one of the spark plug boots trying to get one out. I would like to replace them all without messing with the coils. Is there some kind of splicing kit I can get? Are there any that don't include resistors? What would you guys recommend? Also, I got a few small holes in the bottoms of my mufflers, what do you guys use to tape those up? I got a flat black paint job so I think a few rounds of black high temperature tape would look pretty cool. Any ideas?

 

Spark Plug Cables:
NGK makes spark plug cable splicers or if you have the XJCD, there's an explanation with pictures on how to install new spark plug cables in the coils.

Muffler:
Depending on how small the holes are, you can use muffler cement available at most auto supply places. Or have them welded.

Flat Black paint:
Every spring I give my entire exhaust system, except for the muffler, a few coats of hi temp BBQ paint. It's worked great and the exhaust has lasted about 5 years now.

 

Just my 2 cents....
I use fiberglas to patch mufflers. The hotter it gets, the harder it gets. It works well on old muffers if you don't want tt replace them. Use about three layers of fiberglas matting and hardener and paint it with high heat paint. Works great!

 

Spark Plug Wire Splicer:

pw1) Aftermarket NGK-brand Spark Plug Wire In-Line Splice. This handy little device allows you to cut off a bad original plug wire and splice in a replacement piece, which is really handy, since the plug wires on the original factory coils are basically non-replacable......so if a plug wire goes bad, the whole coil is basically junk! Not real clever factory engineering, but there you have it.

This splicer allows you to extend or replace a damaged or bad plug wire, just like you would splice into a piece of electrical wire. Watertight, screw-on design is made from a high-impact plastic material and adds no resistance (0 ohms) to the circuit. Very handy and practical solution!

HCP2789 In-Line Plug Wire Splice, fits up to 8mm plug wire. Each:
$ 6.00

HCP2789SET4 In-Line Plug Wire Splice, fits up to 8mm plug wire, set of 4:
$ 20.00



Spark Plug Wire Caps:


pc2) Genuine NGK Plug Caps ("Boots)", available in a variety of styles and configurations. All plug caps include weatherproof rubber end boots. NOTE: NGK plugs that begin with the letter "B" are 14mm plugs and are used in all XJ650/700 non-X models/750/900/1100 models. Plugs that begin with the letter "D" are 12mm plugs and are used in all XJ550 and XJ700-X models only.

Okay, before we get going, let's review a little bit about the original Yamaha COILS, PLUG WIRES, PLUG CAPS, and PLUGS used on these bikes.

Factory Yamaha COILS want to "see" a total load resistance on the secondary side (the "going-to-the- plugs" side) of around 20-30K ohms (ohms being a measure of electrical resistance). Electrical resistance depends on a number of factors: wire size, type of material, length of material, ambient temperature, etc. etc. In any case, all factory XJ coils and wires combined---BUT WITHOUT THE CAPS OR PLUGS ATTACHED---are specified to have a resistance of around 11K ohms, +/- 20%, at 68-degrees Fahrenheit. This means anywhere from 8.8K ohms to 13.2K ohms is acceptable. As a side note---and for future reference if you need it---the load resistance on the primary side of the coil (the "main-wiring-harness-connector-leads" side) should be 2.5 ohms +/- 10% at 68-degrees F, meaning a usable range of 2.25 to 2.75 ohms. BY THE WAY, in order to help diagnosing engine performance problems that seem to be "plug-related", always measure the resistance of your coils, both primary and secondary sides, before you start replacing parts. 20+ year old coils can and do fail regularly. If you need to replace your coils, and decide to buy used, original coils "sight unseen", always make sure that the seller checks them for you before you buy them! And also note: most analog ("swinging needle") ohm meters require that the needle be "zeroed" manually before you check ohms each and every time!

Factory coils can also suffer from tiny hairline cracks in their outer plastic housings, leading to electrical shorts which might only show up when the coils get hot, or when the ambient air has quite a bit of moisture (humidity) in it. Running your bike at night, with the tank off, in a VERY dark area will allow you to visually see if there are any tiny blue sparks occuring around the coils or lead wires, in which case the coils are in need of replacement.

Plug WIRES on factory coils are non-replacable, at least not without quite a bit of surgery (which I'm not going to even attempt to cover here). Suffice it to say that if your coils measure out of specs for resistance (as described above), they're junk and should be replaced, either with another factory coil or a pair of the various aftermarket coils that are on the market (Dyna and Accel coils work, but are a challenge to mount correctly in these tight XJ frames). We do offer an NGK plug wire in-line splicer (HCP2789 listed further below) that will allow you to cut off and remove a bad factory wire and replace it with a length of aftermarket plug wire. Aftermarket 7mm copper core plug wire is a good choice to use when replacing factory coil wires, as copper wire (in the lengths that are used on bikes) basically offer an amount of electrical resistance equal to zero.

Spark plug wire CAPS---or "boots"---are the hard plastic insulators that go on top of the spark plug threaded stud, and accept the plug wire from the coil on their other end via a simple "twist-on" method---yes, the plug wire end of the cap has a metal screw that bites into a "screws" onto the end of the plug wire, penetrating the plug wires' inner metal core and making a mechanical connection. Plug wire caps originally were either 5K ohm resistance (on the two center cylinders, #2 and #3, which use the 2-1/2" tall, 90-degree-angled Tokai Denso caps) or 10K ohm resistance (on the two outer cylinders, #1 and #4, which use the short, 1-1/2" tall 90-degree-angled NGK caps---although many of the original outer cylinder caps are not marked NGK anywhere on them). Plug caps have differing resistance ratings due to the use of a tiny interior resistor, and the resistance of each cap can and should be checked with an ohm meter on a periodic basis. Caps that are +/- 10% resistance from specified should be considered bad, and should be replaced. A variety of different size and shape plug caps are listed below, and although neither the original Tokai Denso caps nor the original 10K caps are available, NGK 5K caps come in a variety of original size configuartions and can be safely used to replace broken, missing, damaged, or out-of-spec original caps. They accept up to 7mm spark plug wires easily.

Spark PLUGS on all XJ-series bike were factory NGK models. Although many other brands of plus can be safely cross-referenced to the originals, NGK plugs offer both a value and performance that is quite satisfactory, in both original design configurations or high-performance "Iridium" design plugs. All non-resistor plugs have a resistance equal to zero ohms, while all resistor plugs.....those with an "R" in their part number.....have a resistance rating of 5K ohms. NOTE: all original and replacement plug caps are designed to be used on plugs that have their screw-on insulator stud cap removed, and used with the threaded stud exposed. And the NGK plug caps are specific to either the 12mm plugs (all XJ550's and all XJ700-X models) or the 14mm plugs (all XJ650, XJ700 non-X, 750, 900, and 1100 models).

In conclusion: you can safely use replacement NGK plug caps with a 5K resistance rating with either resistor or non-resistor type spark plugs. If replacing spark plug wires on either original coils, or when using aftermarket coils, it is recommended that you use copper core, non-resistance spark plug wire. Doing the above will give you the total 5-10K plug/cap resistance values that coils need to "see" to perform properly. And finally, always check, with an ohm meter, your coils primary and secondary resistance, and your plug cap resistance, before you start "throwing money" at engine performance problems that seem to be electrically-related!


For 12mm spark plugs: all XJ550 and XJ700-X models:

NOTE: XJ700-X models used "tall" plug caps on all 4 cylinders, while XJ550 models used "short" or "medium" caps on the outer (#1 and #4) cylinders and the "tall" caps on the inner (#2 and #3) cylinders.


XJ550 Outer (#1 & #4) Cylinders:


HCP1316 NGK Plug Cap, 5K ohms, short 90-degree angled boot, for 12mm "D" plugs with a threaded stud on top. Great replacement for the stock plug caps on the outer (#1 and #4) cylinders. Slightly taller than original caps (1.5" tall for these replacements versus 1.3" tall for the originals). Each.
$ 4.00

HCP1316SET2 NGK Plug Cap, 5K ohms, short 90-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 2.
$ 7.75

HCP1316SET4 NGK Plug Cap, 5Kohms, short 90-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 4.
$ 14.00



HCP1676 NGK Plug Cap, non-resistive (0 ohms), 90-degree angled boot, for 12mm "D" plugs with a threaded stud on top. Can be used as a replacement for the outer cylinders (#1 and #4) for those applications that require the use of a zero-ohm cap (for example, using a high-resistance plug wire along with resistor plugs). Almost the same height as originals. Each.
$ 2.50

HCP1676SET2 NGK Plug Cap, non-resistive (0 ohms), 90-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 2.
$ 4.50

HCP1676SET4 NGK Plug Cap, non-resistive (0 ohms), 90-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 4.
$ 7.00



HCP1322 NGK Plug Cap, 5K ohms, medium 120-degree angled boot, for 12mm "D" plugs with a threaded stud on top. Suitable replacement for the stock plug caps on the outer (#1 and #4) cylinders. Slightly taller than original caps (2.5" tall for these replacements versus 1.3" tall for the originals), and the 120-degree angled plug wire end offers some additional clearance as compared to the stock 90-degree right-angled caps. Each.
$ 4.00

HCP1322SET2 NGK Plug Cap, 5K ohms, medium 120-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 2.
$ 7.75

HCP1322SET4 NGK Plug Cap, 5K ohms, medium 120-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 4.
$ 15.00



XJ550 Inner (#2 & #3) Cylinders and XJ700-X all cylinders:

HCP1312 NGK Plug Cap, 5K ohms, straight, for 12mm "D" plugs with a threaded stud on top. Recommended as a suitable replacement for all four XJ700-X plug caps, as the straight-up design helps keep the plug wires off the valve covers, unlike the angled-tip configuration of the original style caps. Can be used on XJ550 inner cylinders (#2 and #3) as replacements, especially when using aftermarket plug wires and coils. Approx. 3" tall vs. the 2.5" tall originals. Each.
$ 4.00

HCP1312SET2 NGK Plug Cap, 5K ohms, straight, for 12mm "D" plugs with a threaded stud on top, set of 2.
$ 7.75

HCP1312SET4 NGK Plug Cap, 5K ohms, straight, for 12mm "D" plugs with a threaded stud on top, set of 4.
$ 15.00


HCP1318 NGK Plug Cap, 5K ohms, tall 102-degree angled boot, for 12mm "D" plugs with a threaded stud on top. Similar in design to all four XJ700-X original plug caps, with the bent-up plug wire tip design. Recommended for the XJ550 inner cylinders (#2 and #3) as replacements for the non-available tall 90-degree tip caps. Approx. 3.25" tall vs. the 2.5" tall originals. Each.
$ 4.00

HCP1318SET2 NGK Plug Cap, 5K ohms , tall 102-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 2.
$ 7.75

HCP1318SET4 NGK Plug Cap, 5K ohms , tall 102-degree angled boot, for 12mm "D" plugs with a threaded stud on top, set of 4.
$ 15.00


All these (and more!) over at:

http://www.xjbikes.com/Forums/viewtopic ... t=180.html

 

To sum it all up, if the plug is all that broke then unscrew it from the plug wire and install the new one you bought from Chacal. Simple and effective. I know the plug cap looks like it was made on the wire but it just unscrews from it.

 

Can I be the dumb guy to ask where I might be ordering these new NGK plug splicers, or boot caps from? I see part numbers, but not sure where to purchase them. Am I missing something?

 

http://www.xjbikes.com/Forums/viewtopic ... t=180.html


Hey Jerry, just let me know which ones you need and send me a PM, and I'll give you the availability info (plugs, boot caps, and splicers are always in stock here!) and shipping/payment/ordering info!