performance spark plug?

brisbane_boy said:
Hey guys im posting this because i bought the otherday a NGK B6HS thinking it was a better plug for performance but i see on the zbox website they say the NGK R7-HS spark plug is better for performance.
Has anyone used 1 of these plugs? are they better?
Another question who has upgraded the lead going from the CDI to the sparkplug with just a lead from a automotive store?
If so what did u get and can u fell a difference?
THanks
DUncan
Click to expand...

Hey there
I have used a ngk bp6hs
I noticed a little more power
Than i was reading on here
(To gap at 0.25 inch
Thats around 6mm)
.wee.
Made a huge differance in power!!!!!!!!!!!!!!!!!!!
 
Anyone that thinks they are going to get a power change with change of sparkplug is kidding themselves. If the motor runs without missing there is not going to be any noticeable difference. Same with the plug wire. If the motor runs it is working.

Jim
 
Ok what would be the best plug for a skyhawk slant head 66cc? Remember it has a domed piston. Would a longer P plug hit the piston?
 
If you use a NGK plug one with HS after the heat range number will be the correct length. Also the HIX after the heat range number Iridium is the right length.

Jim
 
I guess if they make one I would go with a BPR6HS as Iam getting RFI on my bike computer so I would like to try a R plug but I would like to have the longer P plug for my slant head. If they dont make that Ill buy both a P and a R and see whats whats. Thanks for the help!
 
Hi jauguston

Have to say (and from my own experiences) that we are in total agreement: Anyone that thinks they are going to get a power change with change of sparkplug is kidding themselves. If the motor runs without missing there is not going to be any noticeable difference.

About the only thing you may notice between plugs when the engine is at operating temperature is smoothness between different manufacturers spark plugs, mainly due to more consistant firing at the working end of the plug

Ridiculous claims of staggering power increases due to plug changes are far fetched to say the least, with fine wire Iridium giving only greater longevity and reduced spark dropout at the electrode.

Fabian
 
brisbane_boy said:
Hey guys im posting this because i bought the otherday a NGK B6HS thinking it was a better plug for performance but i see on the zbox website they say the NGK R7-HS spark plug is better for performance.
Has anyone used 1 of these plugs? are they better?
Another question who has upgraded the lead going from the CDI to the sparkplug with just a lead from a automotive store?
If so what did u get and can u fell a difference?
THanks
DUncan
Click to expand...

I just installed a ngk bpr6hix
Engine seemed to have a miss.....
I know your not meant to gap these plugs but
I opened up the gap...Now Goes Awsome !!!!!!!!!!!!!!!!!!!brnot
 
I heard there is a shop coming out with a high performance handle bar grip that is supposed to be good for a extra 7-9 mph.

Jim
 
i am new herebrnot but i read all the threads and decided to replace the plug wire but wanted a finished product so went down to the yamaha dealer and bought a 7mm plug wire for a cycle...cut it and put it on ...this is a nkg plug wire ...fits tight works EXCELLENT....
 
i'll answer that one.

it stays on.

i replace the plugs (NGK B7's) and wire (7mm copper core) on every engine i build.

the main reason i do this, is the first engine kit i had, the factory wire was brittle and fell apart when i tried to install it. i've also seen a few bikes where the clip inside the wire falls out, and we had to do some Macguyver-ing to get the thing to stay on to get home.

one stock plug i had, the electrode was bent over to the side of the tip at an extreme angle, where if i tried to fire the bike up, it woulda had a severe miss. another one i had was chipped.

also, i like to hide the CDI out of the way, and i need a longer, flexible wire to achieve this.

i agree that in general, upgrading a plug and wire won't suddenly give you 10 horsepower, but it might be the difference between motoring or pedaling home...
 
bairdco said:
i'll answer that one.

it stays on.

i replace the plugs (NGK B7's) and wire (7mm copper core) on every engine i build.

the main reason i do this, is the first engine kit i had, the factory wire was brittle and fell apart when i tried to install it. i've also seen a few bikes where the clip inside the wire falls out, and we had to do some Macguyver-ing to get the thing to stay on to get home.

one stock plug i had, the electrode was bent over to the side of the tip at an extreme angle, where if i tried to fire the bike up, it woulda had a severe miss. another one i had was chipped.

also, i like to hide the CDI out of the way, and i need a longer, flexible wire to achieve this.

i agree that in general, upgrading a plug and wire won't suddenly give you 10 horsepower, but it might be the difference between motoring or pedaling home...
Click to expand...

How do you hide the cdi????
Where do you mount it???zpt
 
futher at night you could see the electricty jumping all oner the head..this is because of the poor quality in which the factory leads are connected ..the yamaha plug wire is solid in it's connections and the rubber is thick and it firs the plug with a tight connection...not sure there is any hp gain
 
I fitted a BP6HS plug to my stock 55cc and it takes ages to warm up. With the original plug, it would come on power as soon as it started, now, I need choke for 2 mins, then it is still erratic for a few more minutes, then it runs ok. I definitely did not see any power gains over the stock plug, if anything I think it is a touch slower up the hills now.
My take on the plug wire, which I have not changed yet, is that they will not give you more power, but if it has less loss than another lead, it will appear to give more power.
 
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these motors are great fun and you can do a few things to make them run smoother and more reliable...sanding out the carb intake tube to remove any LET OVER CASTING DEBRIT ..replacing the factory plug wire with a better constructed one..i don't know that any of this gives more hp...but all these changes made a lot smoother more reliable runnuing bike..i fixed everything i could so i would'nt run into problems...did not use rag sproket that came withe kit...got rid of the coaster brakes..used dick front and drum in back...the result never a break down so far and lots of trouble free motoring.....
 
vk7hch said:
I fitted a BP6HS plug to my stock 55cc and it takes ages to warm up. With the original plug, it would come on power as soon as it started, now, I need choke for 2 mins, then it is still erratic for a few more minutes, then it runs ok. I definitely did not see any power gains over the stock plug, if anything I think it is a touch slower up the hills now.
My take on the plug wire, which I have not changed yet, is that they will not give you more power, but if it has less loss than another lead, it will appear to give more power.
Click to expand...

I did have this problem
How to fix this you need to gap the spark plug!!!!
Around 0.25 Inchs
Or aprox 6mm gap
Made my bike goes heaps better!!!!!!!!!!!!!!!!!!!!
And Regarding need to choke this...I thought this is normal..AS i have owned a few of these bike
Normaly put full choke on at start up then move the lever down just a touch ..Than around 100 Meters take choke right off????zpt

Also i have Had my bike not reving right out
The Carby intake needs to be sealed off..Poople say on here to put a o ring on it....But somehow i couldn't work this out...So i just used elec tape
Than my bike runs Great...Revs right out going up hills!!!!!
 
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matesrates said:
I did have this problem
How to fix this you need to gap the spark plug!!!!
Around 0.25 Inchs
Or aprox 6mm gap
Made my bike goes heaps better!!!!!!!!!!!!!!!!!!!!
Click to expand...
That's a plan, will purchase a gap gauge in the morning, I must admit I am using it out of the box.
matesrates said:
And Regarding need to choke this...I thought this is normal..AS i have owned a few of these bike
Normaly put full choke on at start up then move the lever down just a touch ..Than around 100 Meters take choke right off????zpt
Click to expand...
Sorry, I should have said that with the stock plug, choke to start, turn off straight away and power avail!!. Just noticed the change after putting in NGK plug. Will gap it tomorrow.
Thanks
 
vk7hch said:
That's a plan, will purchase a gap gauge in the morning, I must admit I am using it out of the box.
Click to expand...

Well wasn't that depressing, checked the plug gap on the BP6HS, it was spot on 25 thou. No difference in performance, although I noticed that the insulator was much paler that with the china plug.
In desperation, I put the spare plug that came with the motor in, and wow, it ran much better, 7kmph faster up the hill I ride every night to work.
So either I had a dud plug, coz I am not going to say that the stock plug is better than an NGK, or I don't know.
I didn't have time to muck with the card slide clip, I thought that it should have been right considering the beautiful brown that the stock plug is.
Do I need to try a different heat range perhaps? I am a relative newbie to 2 strokes.
Cheers
Chris auflg
 
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