Spark plug HELI COIL?

I need to Heli coil my # 4 sprk plug hole while the head is off.

Not sure what to buy, do I drill it or tap it? What size do I buy? The hole is very stripped.

Thanks

there is aproduct available at most napa stores called save a thread it is a solid steel insert and install tool that i have used many times in the past a heli coil can actually blow out so i recommend using these solid steel inserts they are very easy to install the directions are self explanitory and i've have never had one pull out. in fact i have a set with me in my track box and a set at home a very good product.

Most older KZ's had 14mm x 1.25 threads. These are the sparkplugs starting with a "B"... B7ES , BR8ES , BPR7ES...... If the sparkplug starts with a letter "D" they are 12mm x 1.25.... DPR7EA-9, D7EA, .... Depends on what is supposed to be in there...

Oh those plug #'s are NGK brand

i would stay away from helicoils if I was you... especially on the sparkplugs. They are rarly a successful fix and almost never a permenant fix. They are great for REALLY screwing up a fixable head to the point that they are beyound an Easy fix. "Time-Sert" is another brand of solid inserts that are availible and work really well .. they have a shoulder on the top of them... along with a countersink bit in the kit. leaving a completly flush mount when done correctly. I think there are 2 or 3 different lengths availible. more then likely the long one will work great! Good luck

time serts are very hard to get in canada wurth is the only company that has rights to them up here that is why i recommended save a thread you can get them from any napa dealer and they are identical to the timeserts installed the same way and everything.

i helicoiled #3 on the 1100 two years ago with no ill effects.
of course i have not changed the plugs since then :whistle:.............................

Right on thanks guys. I have NGK BBES plugs so I will buy 14mm x 1.25 threads. I will buy Save a thread from Napa, here in Canada.

You guys are great. You make fixing a bike so much easier.

Thanks

Stevie! "of course i have not changed the plugs since then "... :ohmy: :huh: :dry:

NGK plugs are what, $2.50 each, you cheap S.O.B.! :S

if you know how to sync your carbs you don't need to change plugs so often