*

Plugs tend to be a topic of dispute on the VTX – from the well known “broken electrode” Bosch plugs to the “overpriced” Uber plugs come the “required” iridium plugs native NGK. I find that each plug has its place depending on the rider’s choice, talk habits/style and also the bicycle itself. Ns personally operation the Bosch +4 4419 plugs v no okay effects and also the expense is just right for me – but everyone’s experience tends to it is in a little different, castle say range is the spice that life…

Here room the facts about plugs and the VTX 1800…The shallow plugs on the VTX (front ideal and ago left) have tendency to watch nicer 보다 their counterparts, the deep plugs (front left and earlier right). This is typically a side-effect the the break-in ~ above the motor and tends come “work it’s way out” after ~ the an initial 6,000-8,000 miles. If you take apart a cylinder head and look there is no discernable difference between the 2 plugs positioning in the head, lock are an extremely symmetrical. Each plug is set next to an intake valve top top the outer edge the the burning chamber and they both have the very same distance from the exhaust valve. Based upon that information there have to be no difference in fouling between the shallow and deep plugs in a brand-new engine, yet let’s take this one step further… There are two oil jets in the crankcase collection at the basic of the cylinders the spray oil onto the connecting rod’s wrist pen area, these oil jets not just lubricate the wrist pen to piston connections, but additionally lubricate the cylinder wall surfaces and aid keep the piston itself cool. In a new engine the rings space not seated in yet and also the over spray from the oil jet that enter the cylinder wall surfaces can obtain past these unseated rings and also up into the combustion chamber. There it is burned off, but it can very first contribute come plug fouling. The oil jet on the VTX face the “deep plug side” the the cylinders and also therefore may be a contributing element in the deep plugs spring worse the the shallow persons on newer engines.

You are watching: 2003 honda vtx 1800 spark plugs

The 2002 VTX’s came v a plug the is one step colder than the 2003’s and up. This bikes room not known for producing pretty looking plugs to begin with, therefore these colder plugs to be renowned because that fouling early and often. One of the culprits that compounded this fouling problem is the absence of a an excellent ground on these bikes. Most of this trouble can it is in remedied by reworking the grounds as in-depth in this article, however even the is no sure solve for every riders in all conditions and environments. I normally tell human being that if you’re running the chillier plugs (which to be stock because that 02’s) and have good results (i.e. Nice, pretty, tan plugs) then stick through it. I think that “if it ain’t broke, don’t resolve it”.

Now for those with 02’s who room still fouling – also after reworking the grounds, checking her coil connections and making sure the plugs room properly mounted – then go ahead and also swap to the name is plugs which are stock in the 03+ VTX’s. Generally speaking this solves many people’s difficulties with fouling, or at least makes them as great as can be meant from these bikes. On rare occasions if someone through an 02 has actually really good looking shallow plugs yet badly fouled deep plugs I have recommended sticking v the stock 02 (colder) plugs in the shallow holes (if that ain’t broke…) yet running the 03 (hotter) plugs in the deep holes. ~ above these rare occasions it seems to work far better than all cold or all hot plugs across the plank – simply a small “food because that thought”.

Proper installation of plugsThe most typical mistake I view when guys install plugs on your bikes is the they flip open up the manual and see 13 ft/lbs as the recommended torque and go right to work transforming plugs there is no realizing they’re make a mistake. The hand-operated spec because that a plug is 13 ft/lbs yet this concerns old plugs i beg your pardon have currently been installed and also seated properly. Once installing new plugs you have to seat them finger tight an initial and then usage a ratchet come tighten lock 1/2 a revolve further. Act this seats the crush washers properly and will remove the possibility of oil blow-by comes up the threads when the engine is running. Oil blow-by will avoid the plugs from acquiring a an excellent ground and also further aid the plugs in fouling. Once you download a brand-new plug appropriately you will actually feel the to like washer seat at around 1/2 a turn past finger tight and it gets much tougher come tighten after the – that’s once you stop. Once your plugs space properly mounted you can pull and check castle anytime you want and also then reinstall them using the hand-operated spec that 13 ft/lbs. Constantly use a tiny bit that anti-seize top top the plug threads before installing them, and NEVER download plugs right into a hot (or even warm) motor.

Something to watch for as soon as installing plugs – perform NOT cross-thread them. V steel plugs and also aluminum top it is sadly too usual an event to see. If you’re a new “wrench” and also afraid you might make this mistake then walk to the auto store and get yourself around a foot of 3/8″ fuel line. It will price a pair bucks however you deserve to slide it over the insulator ~ above the plug and also use it come thread the plugs right into the heads. What makes this fool-proof is that if you execute actually start to cross-thread the plug the fuel line will certainly slip top top the plug prior to it will ever before actually cross-thread into the head. It additionally helps with getting those deep plugs began if girlfriend don’t have a plug socket.

See more: How Many Beats In A Crotchet, Time Signatures: A Beginner'S Guide

ManufacturerOEM (03+ stock)Cold (02 stock)*I tried to verify as many plug number as possible but ran into difficulties finding any type of concrete answers from many plug manufacturers. The plugs v “*” next to them are confirmed by the manufacturer together a direct cross-reference, the others space old numbers that were floating approximately the VTXOA.
Spark plug cross referencefor the VTX 1800
AC Delco*41-80641-801
AutoliteAPP3924APP3923
Bosch Platinum +4*44194418
Champion Copper*RC9YC4RC9YC4
Champion7346
Champion dual PlatinumRC10PYP4
DensoVK16PRZ11VK20PRZ11
DensoPK20PR11
Denso Iridium*IK16
NGK*IFR5L11IFR6L11
NGK IridiumBKR5 EIX-11BKR6 EIX-11
Splitfire*SF522DSF392C
Splitfire Platinum*TP522DTP392C
Uber Power*FZX5iLFZX6iL
Gap 1.0 – 1.1mm (.038″ – .043″)