Spark Plugs

[J.B.]

What do you guys run for plugs? previous owner of my R was running NGK BPR7ES plugs. I've never see or heard of these plugs being run in R's before.

[brokenmike]

NGK. B8ES. No problems here.

[jcs003]

BR8ES...is there a dirrrefence between the B8ES and the BR8ES?

[fearlessfred]

i think r is for resister

[jcs003]

Originally posted by fearlessfred
i think r is for resister

but is their a difference in performance?

[wild250rman]

Is the cylinder stock or aftermarket? if aftermarket it maybe the one recomended, If stock save your money and run the B8ES and you will be fine.

[fearlessfred]

go to search at the top of the page type in e3 spark plug and go to the second to last post [moyer 17901] he pretty much sums it up as far as spark plugs go, in my opinion

[morse250r]

i always ran a br8es but i switched to the 9

[fearlessfred]

yea the 9 is colder and thats what i allways ran,if your running wide open all the time,you should have a 9

[jcs003]

Originally posted by fearlessfred
yea the 9 is colder and thats what i allways ran,if your running wide open all the time,you should have a 9

on this logic a 7 should be ran in lesser throttle scenarios (tight woods). is this correct?

[fearlessfred]

no ,if the plug is not loading up or fouling an 8 is fine. I run a 9 because i ride the sand dunes wide open if the plug is fouling and is jetted correctly than i guess a 7 is in order is your r stock

[LONG-ROD]

all your doing is changing the temp in the cylinder.. I run a 9 in summer and a 8 in the winter.

[1promodfan]

Has anyone tried the NGK iridium plug??

[wild250rman]

I used them in my 07 400ex to help the cold starting issue and fouling associated with over choking. It helped a bunch for that but were a little on the expensive side.

[jcs003]

i dont foul plugs on either of my 250r motors.:confused: my friend who had a yz250 would foul a plug every once in a while and i never knew why.

i just change the plug in my 250r when i change the gear oil. which is after alot of riding.

[LONG-ROD]

plugs foul because of jetting...

[Ruf Racing]

Originally posted by LONG-ROD
plugs foul because of jetting...

^^Ageed^^ If your Jetting is spot on, no fouling!

[wild250rman]

x3

[addictedtomud]

I run NGK B8ES all year long, hot or cold weather, have done so for many years with no problems. Motor sizes from bone stock to 350pv.

[fearlessfred]

i agree on proper jetting. but just the same,heres a quote off an nkg site highly tuned engines need colder spark plugs. [were nkg spark plugs are used , install plugs with a higher heat range INDEX NO. than stock units] if you do not know the heat range its best to install a fairly cool plug. if the the plug tends to foul during operation,thus causes misfiring change to a lower index no. the rule of thumb is to use the coldest plug that the engine can tolorate with out leading to fouling this is from a nkg site . nkg usa has 5 pages dedicated to selecting the proper heat range. most people that i have helped tune ther built motors were way oversize on there main jet .once we go with a colder plug and leaned it out doing wide open plug chops there would be nice gains in perfomance