Normal spark plug Vs iridium ie Denso IW27 or NGK BR9ES



  • Hi everyone just rebuilding the DT, and what is everyone's thoughts on normal spark plug Vs iridium ie Denso IW27 or NGK BR9ES , Mechanic that re-bored engine says Iridium are overrated your thoughts please



  • For the price of the NGK one they're worth the money. Although don't expect a noticeable difference. Just a reliable spark.



  • Cheers Calum
    Thanks for info,also is there a link on site to how to turn bike into premix ,or is it just a case of blanking of oil pipes,also you seen those pedmoto exhausts they sound dam good



  • I've used the Iridium Plug for a while now and they don't last on my bike atleast. The BR9ES is just fine



  • So what I mean is that a set of superfire plugs for my starlet is £100. Personally that isn't worth the money. A set of iridiums are £30.

    A spark plug for a dt is what 6 quid. And iridium is 9 quid. So its not a lot of money. They are supposed to last longer but if your bike runs overly rich or lean then sure it will wear an iridium faster. But thats not a fault of the spark plug.

    I don't swear by them. But I have always ran them. For no reason other than they cost more, so that must mean they are better. Poor logic for sure.

    I have no experience with the pedmoto but they look good. If they're stainless steel then they should last longer than a dep which was my gribe with the dep.

    As for the oil blanking. I would remove the oil pump. Oil cable and oil lines and tank. You need to gap the oil line from the inlet manifold to reed block as this will cause an air leak.

    The other one is that there is a cog driven off the crank shaft that drives the oil pump. Although the oil pump is removed this cog will still turn. So remove the cog clutch cover to stop this cog for spinning. Freeing up 0.0000001% parastic loss from the engine. Every horse counts!