bosch platinum +4 plugs

paulson_shawn · Posted: July 14, 2007, 2:43 am Post subject: bosch platinum +4 plugs

i looked up an older buick 4 cylinder that runs autolite 63 plugs and it says a bosch platinum +4 (4 grond terminals) 4479 will work with that engine. does that mean it would also work in my xs650 since ngk bp7es is interchangeable with autolite 63's?

INXS650 · 650Rider Supporter Joined: Mar 22, 2007 Posts: 645

The ignition system on these bikes aren't powerful enough to fire the plugs properly with a single .030 electrode, what makes you think they'll fire 4 of them at more gap? Stick with the standard plug unless you get a boyer ignition to liven things up a bit.

paulson_shawn · Posted: July 14, 2007, 5:11 pm Post subject: Re: bosch platinum +4 plugs

i do have a boyer ignition on my bike now, but i was wondering if there was any other reasons the plug would b wrong?

INXS650 · 650Rider Supporter Joined: Mar 22, 2007 Posts: 645

If you've got the power to fire em, go for it. It should pick you up a HP or three.

paulson_shawn · Posted: July 15, 2007, 5:29 pm Post subject: Re: bosch platinum +4 plugs

i tried them and they made my engine rev up at idle (too lean) and after all the hassle getting the carbs tight the first time i don't want to change.

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