Can anybody tell me what spark plug I should have in the 2011 Sherco ST290? The manual says NGK BP5ES, but my bike has a DENSO in it (NOT SURE OF THE CODE), I allways like to use the NGK Irridium plugs if I can in my bikes so does anybody know if these are ok for Sherco's and a code for them if poss thanks.

http://www.splatshop...ug-bpr5eix.html

Yes its fine to use the iridium plug in your sherco. As is the regular the NGK BP5ES and the Denso's. The iridium tip one just helps a little with anti fouling.

Edited January 20, 201412 yr by lewis cosgrove

The iridium plugs can stand higer temps which is good on high performance high reving bikes. On a trials bike, although they will not hurt it, are not much benefit vs cost. Infact a standard correct grade plug may be less affected by fouling due to more contact area of the electrodes so if a section fouls the spark can jump to a clean spot.

I run an irriduim plug in my sons gas gas 50 and it will last over a year as it is a bit of a rev machine, However in the sherco I can run it richer without fowling issues as soon as I went back to the standard ngk plugs.

Just look at what the factory bikes are running and go figure what is best.

Also make sure your running a 0.6 to 0.7mm gap.

I am not sure if the standard Denso plug is better than the NGK, but mine has been in for over a year without issue, so it works it seems.

I still have a couple NGK Platnum stashed away, but have not needed a change.