pushing plugs out

[05Special]

after riding for a bit the plugs unthread.. They are tight, what would cause this?

[Dinner]

Usually spark plugs threading themselves out are a sign of Detonation

[tnr]

The banshee engine has alot of vibration and that is why the plug can come loose. They make a spark plug lock so you dont have to worry about it anymore. Just search banshee spark plug on ebay and you will find them.

[NYUK]

plugs backing out is usually a sign of something more than just vibration. that plug lock and your engine detonating can lead to an expensive fix.we need more info. what octane fuel, cool head? what domes. jetting ect.

[05Special]

coolhead, 19cc, 93 octane...normally runs good with the 93, but after the rebuild it started runnning very badly..I'm putting the stock head back on.. I've had way to many problems with the coolhead..

[tnr]

plugs backing out is usually a sign of something more than just vibration. that plug lock and your engine detonating can lead to an expensive fix.we need more info. what octane fuel, cool head? what domes. jetting ect.

Good call. Awhile ago I remember that a buddy of mine was having a similar problem and he got one of those plug locks. I am sure he did an extensive test because that was a couple of years ago and his shee is still running strong. :thumbsup:

[sheefreak]

Good call. Awhile ago I remember that a buddy of mine was having a similar problem and he got one of those plug locks. I am sure he did an extensive test because that was a couple of years ago and his shee is still running strong. :thumbsup:

 

One of the dumbest things you can do is put a plug lock on a banshee, especially if it is anything but bone stock. It is deto! Your motor is giving you a generous heads up when starts to back plugs out. The fact that your buddy has got along a couple years w/o blowing his up w/a lock just means his motor is not detonating. But I bet he would want to know if it started. What happens if all the sudden he loses a stator side crank seal and leans out and starts detonating. Most likely he will have no clue untill it is too late.

 

On to the problem... I would not run pump gas w/19cc domes first of all. You may get away w/it, but you are on the ragged edge. Temp changes during your day of riding could make all the difference. Deto can be caused by too much timing, too much compression(or rather too high a ratio and improper fuel) air leak, or any combination or cause of being lean. You may want to do a leakdown test, and if your timing is any more than +4, I would back it down till you figure out what is going on. If it ran rine w/stock head, and only change is cool head, fuel is definately your problem!

 

Oh, and TNR, I am not picking on you, but just like running your quad in the dirt w/o air filters a plug lock is always a bad idea. Tell your buddy they make a great plug wrench though =)

Edited March 26, 2008 by sheefreak

[05Special]

Thanks guys for all the input!!! the hq always helps out...Well I am going back to the stock head. I need some studs if anyone has any and the coolhead is up for grabs..I also finally broke down and bought a trinity single carb setup....So after the stock head will solve my compression issue, and the carb should solve aything before the intake ports...trying to shoot a little more for reliability..thanks guys, appreciate it... you may have just saved me a motor!!!! :biggrin:

[sheefreak]

Do what you wish, but you can prolly pic up some 21 or 22 cc domes cheap and run the cool head and then you will have it later when you decide to build a monster. :cool:

[ASRBanshee]

to tell if your plugs are being tightened in the first place check the ring where it sits on the cylinder head. Or in other words the metal seal that is movable from the start of the threads. It should be a dark gray to a black color. If it is not, or it is sooty air is passing thorugh and you need to tighten them more.

[tnr]

One of the dumbest things you can do is put a plug lock on a banshee, especially if it is anything but bone stock. It is deto! Your motor is giving you a generous heads up when starts to back plugs out. The fact that your buddy has got along a couple years w/o blowing his up w/a lock just means his motor is not detonating. But I bet he would want to know if it started. What happens if all the sudden he loses a stator side crank seal and leans out and starts detonating. Most likely he will have no clue untill it is too late.

 

On to the problem... I would not run pump gas w/19cc domes first of all. You may get away w/it, but you are on the ragged edge. Temp changes during your day of riding could make all the difference. Deto can be caused by too much timing, too much compression(or rather too high a ratio and improper fuel) air leak, or any combination or cause of being lean. You may want to do a leakdown test, and if your timing is any more than +4, I would back it down till you figure out what is going on. If it ran rine w/stock head, and only change is cool head, fuel is definately your problem!

 

Oh, and TNR, I am not picking on you, but just like running your quad in the dirt w/o air filters a plug lock is always a bad idea. Tell your buddy they make a great plug wrench though =)

No offense taken at all. I am fairly new to all this and learning more every day. The only reason I said anything is cause it worked for him. I personally would never run one. I bought a bike that wasnt running and fixed it and during all of that I found the guy who owned it before me had a bandaid for everything. Hence being it wasnt running. I got off the phone with the guy that is running one of those plug locks and he is running it cause he messed up the threads on the head for the plug. The only reason he hasnt fixed it is he is getting ready to drop in a 421 cub.

[boonman]

One of the dumbest things you can do is put a plug lock on a banshee, especially if it is anything but bone stock. It is deto! Your motor is giving you a generous heads up when starts to back plugs out. The fact that your buddy has got along a couple years w/o blowing his up w/a lock just means his motor is not detonating. But I bet he would want to know if it started. What happens if all the sudden he loses a stator side crank seal and leans out and starts detonating. Most likely he will have no clue untill it is too late.

 

On to the problem... I would not run pump gas w/19cc domes first of all. You may get away w/it, but you are on the ragged edge. Temp changes during your day of riding could make all the difference. Deto can be caused by too much timing, too much compression(or rather too high a ratio and improper fuel) air leak, or any combination or cause of being lean. You may want to do a leakdown test, and if your timing is any more than +4, I would back it down till you figure out what is going on. If it ran rine w/stock head, and only change is cool head, fuel is definately your problem!

 

Oh, and TNR, I am not picking on you, but just like running your quad in the dirt w/o air filters a plug lock is always a bad idea. Tell your buddy they make a great plug wrench though =)

 

 

Freak, please understand that you are talking about two seperate things here. Running lean, (air:fuel ratio) and detonation. You list running lean as a cause of detonation, and it simply is not. While it can aggravate a detonating engine, it will not cause detonation. Alrthough, and obscure happening while running lean, it will heat the bike up, and perhaps increase slightly the chance of detonation, but the piston will likely melt and smear the exhaust port long before the signs of detonation show up. Now, causes of detonation are what you have written, too much advance, too much compression, both of which are related to not having enough octane to combat these things. They aren't necessarily bad on their own, but with not running the proper fuel, it will cause problems. Now, one other thing that will cause detonation, and not have anything related to octane would be an improper squish. Something that must be checked at engine assembly. Now, running lean will aggravate an already detonating engine, but like said, most likely will not cause detonation on it's own. If you blow a hole in the center of the piston, detonation, melt the exhaust side of the piston, and smear the cylinder wall with aluminum, lean condition. But, at any rate, if the plugs are backing out, you have other issues.

[05Special]

well when it was happening I couldn't even get the bike to idle..I'm fairly decent with jetting but by no means great at it. No matter what i changed in the carbs the bike wouldn't change. When it would rev up it would take a while to rev back down to idle..my first thought was air leak somewhere but I checked every square centimeter of the motor. There was also some unburned gas in the exhaust..My timing is stock so it is shouldn't be advanced to much unless it change on its own I'm thinking the fuel issue and detonation at this point. I just put the stock head back on in order to run regular fuel..I should have it up and going by morning.. I'll be sure to let you guys know how I make out....

[sheefreak]

Freak, please understand that you are talking about two seperate things here. Running lean, (air:fuel ratio) and detonation. You list running lean as a cause of detonation, and it simply is not. While it can aggravate a detonating engine, it will not cause detonation. Alrthough, and obscure happening while running lean, it will heat the bike up, and perhaps increase slightly the chance of detonation, but the piston will likely melt and smear the exhaust port long before the signs of detonation show up. Now, causes of detonation are what you have written, too much advance, too much compression, both of which are related to not having enough octane to combat these things. They aren't necessarily bad on their own, but with not running the proper fuel, it will cause problems. Now, one other thing that will cause detonation, and not have anything related to octane would be an improper squish. Something that must be checked at engine assembly. Now, running lean will aggravate an already detonating engine, but like said, most likely will not cause detonation on it's own. If you blow a hole in the center of the piston, detonation, melt the exhaust side of the piston, and smear the cylinder wall with aluminum, lean condition. But, at any rate, if the plugs are backing out, you have other issues.

 

Boonman, good to see you around, haven't seen you in a while. I must say I got a little excited as the last thing I wanted to see happen was this guy throw a plug lock on his problem and be very sorry later. I did not mention the squish issue as he is running stock setup w/mass produced domes that are a little more on the friendly side as far squish angle, cut etc. I probably didn't make myself clear on the lean issue. As you stated I was trying to explain as far as being on the ragged edge of detonation and then introducing a slight lean condition into the mix could and would be a very bad thing. Thank you for making it a little more clear.

[gregrob]

what do you have your timing set at?

 

 

Nothing wrong with a coolhead if it's set up properly. You need to do a compression check and report back. If it's over 145-150psi pump gas is a no no. IMO. Especially if your throwing any timing at it.