Iridium Spark Plugs

From Honda Trail Bike Wiki

I have decided to fit a set iridium spark plugs to my 02 Transalp they are supposed to Improve Fuel Economy, performance and make the engine run smoother. I am mostly interested in the later as I find my ALP to be a bit vibey. More info about them on the NGK site [NGK]

Although the seem too good to be true they are about £8 each ouch!

I understand from postings on the Transalp forum that changing the 4 plugs is not straight forward and may involve removing the radiator and or tank to get to the hidden ones.

I will photo the whole process and post up later along with my conclusions as to any improvements.

What a flipping palarver 3 hours to change the spark plugs mind you the up side with the iridium plugs is that they supposed to last 18000 miles.

Conclusions and Comments

After initial disappointment in the level of noticeable improvement I am very pleased slightly smoother at the lower end and smother / better top end with less vibes when pushing on. Are they worth the extra expense? yes I will fit them again

These pictures and comments are to be used in conjunction with a service manual.

They are used at your own risk and are a pictorial record of the procedure I carried out

If you don't have the spark plug spanner that came with bike I would stop now unless you want to remove the radiator as well

Left and right mean left and right while sitting on the bike

Left hand side plug removal

Left hand side rear cylinder very assessable what you see is what you get no problems.

this where the real fun starts

If you look through the hole in the left hand side fairing you can just see the HT lead of the plug.

Yes you need to remove the LHS fairing to get the plug and even with the fairing removed things are very tight

HT lead removed and plug spanner fitted

Right hand side front cylinder

Not too many problems bit tight for space behind the RHS fairing but easily do able

Now on to the last plug - rear cylinder RHS - You can just see the plug's HT lead between the frame and the top RHS of the cylinder head

Unbolt the petrol tank and lift it up - I would recommend tying the tank to the handle bars with a cable tie - you do not want the tank to fall on the floor big big money to replace.

The tank cable tied to the bars

You can now access the plug.