Sparkplugs: Can use these?

[DCgs450L]

As I am still in the process of getting my bike road worth I have yet to find the appropriate Bosch spark plugs for my bike but for certain I will be installing four of these beauties.


I found the Bosch Platinum2 years ago and now the only plugs I ever need to replace are from any vehicle I get that doesn't have them. A couple of years ago Bosch came out with the Platinum4 and now it has become my new best friend.

In both my old ford and chrysler I kept getting fouled plugs after 10K miles. I found out that it was the Bosch Platinum2's (recommended by factory). I put in Autolite Double Platinums and the problem went away in both vehicles. I have heard a lot of mechs dogging Bosch plugs, so don't believe the marketing (that you quoted) You can engineer a test to give whatever results you want. I refuse to use them anymore, even in my new car. Better off staying with the recommended NGK unless they aren't working. Don't expect any noticeable gains from a different plug that wasn't engineered for that engine.

[rednutt]

I wonder what your plug reads are after fully warming up and then a few miles of steady minimal throttle testing? Sounds like a possible pilot circuit problem. Stock intake/exhaust?

Hi keith,
The exhaust on my bike is a 4-1 the filter is a Uni-filter in the stock air box! NGK told me to try the DPR8EA-9 As the self cleaning is not happing on the spark plug.There idears are turn the bike off at Traffic lights or intersections save too much idleing or ride it like you stold it 1st and 2nd all around town.I dont think I have a carb problem because the bike gos hard on the highway and when I get to a town its all good no splatering from intersections for a wile untill I cruse around town then it seemes to start to play up. give it a good flog on the highway all good again...

[Clone]

Rednutt, I have to go with Keith on this, you have a fuel delivery problem, which on these bikes can only mean carbs. If you plugs get dirty and you have to run it at high rpms all the time or they foul, you are only skirting an issue rather than addressing it. Running a hotter plug is fine but you need to take a look at what is causing you to need a hotter plug.

[KEITH KRAUSE]

Like I said, do some plug chop/tests at minimal, 1/3 and full throttle and see what the plugs say.
If the plugs are dark only at minimal throttle, that suggests a carb issue, most likely the pilot circuit.
If the plugs are dark at all tests, that suggests either carb issues at all three jetting circuits, or a weak spark. Higher rpm operation can help a weak spark but it will eventually get worse and the carbon build up (from either weak spark or rich mixtures) creates other problems.

[duaneage]

Check the spark plug boots or better yet just replace them. A set of four costs 16 dollars and they look better and work better in the rain.

But again, don't fix carb problems with spark plugs.

[bwringer]

I tried a set of resistor plugs (BR8-ES, normally B8-ES) on my GS850 just for giggles.

End result? Diddly squat. No difference at all in how it ran, started, etc. And I still got a ton of interference on the El Cheapo FM radio I was trying to use to lighten my commute.