Will shee run a little bit longer

[Drturbodiesel]

Hello fellow banshee owners. I'm a new member first post. I got a 05 bone stock doesent look like engine has ever been into. I noticed that right cyl was spitting and sputtering at times in lower to mid range. Idles fine pulls hard thro upper rpm. I decided to check compression before I started messing with fuel spark etc. Found left cyl to have 130 right 112 cold. It will finally build 120 after a lot of kicks. Anyways it almost winter would it hurt to run it the rest of this fall or am I risking more sever engine damage? Also are 05 cylinders lined or can they be bored ? Thanks

[Jereme6655]

Welcome to the site!!! Good job on testing the compression.....that and a leakdown test can and should be used as tools to diagnose and check your motor....even BEFORE you rip into it.

 

To answer your question there is no real answer.....could you be fine for the rest of the season....sure. Could your piston skirt break off and do a cha-cha dance all over your cylinder walls and head...sure. You said its spitting and coughing a little bit down low.....it could be a leak or it could be a jetting issue. what do your plugs look like? as long as your jetting is okay and you are running quality fuel AND you do not have an air leak.....i wouldn't worry about riding it for the remaining season.

 

Stock cylinders are NOT nykasil plated....so you CAN bore them without a problem. You can bore the banshee cylinders to a MAX of .080 over......so as long as your good with maintenance and pay attention to your motor you can bore it 8x's......that will last you a LONG time.

[Drturbodiesel]

Thanks for the reply. I kinda knew it could go either way on the piston just wanted a second opinion. My plugs look ok maybe a touch on tha fat side. As soon as I noticed the problem I sprayed wd 40 all over intake and around base gaskets etc with engine running no leak found. I can ocasonally hear a little piston slap at idle on that side. I am very ticky about how my stuff runs I guess from being a automotive tech all my life. Previous owner though everything was fine. Anyways are all banshees loud around the water pump area at idle? From what I can tell it's normal charchteristics of this machine.

[Drturbodiesel]

i spoke with a retired honda tech today. he said the compression test method i used dident mean jack cause i was only testing above the ports. i went to my regular cycle shop and he said basicly the same thing. he told me to clean carbs put in some fresh plugs and let her rip. forgot to mention the retired honda tech said i prolly have a stator problem and that banshee was bad about stator problems burning one side up before the other. i am kinda lost at this point. its hard to ignore experience but cant put it over logic. my banshee will run perfect one day unless i get mad and sell it.

[Jereme6655]

i spoke with a retired honda tech today. he said the compression test method i used dident mean jack cause i was only testing above the ports. i went to my regular cycle shop and he said basicly the same thing. he told me to clean carbs put in some fresh plugs and let her rip. forgot to mention the retired honda tech said i prolly have a stator problem and that banshee was bad about stator problems burning one side up before the other. i am kinda lost at this point. its hard to ignore experience but cant put it over logic. my banshee will run perfect one day unless i get mad and sell it.

 

 

But you gotta remember that was a honda tech talking yamaha banshee to you........that would be kinda like a regular combustion engine guy telling you all the things that are wrong with turbo diesels)

 

compression tests on 2 strokes will give you an idea of where your cylinders stand in terms of how your banshee will preform. Yes it wont show compression until the piston is ABOVE the ports......but that's like saying your compression test on a 4 stroke doesn't mean shit until your valves close (kinda one of those no shit sherlock type comments).

 

the test is used to tell if you should start looking into a rebuild or not (under 100 psi in either jug)

[DallasGDub]

i spoke with a retired honda tech today. he said the compression test method i used dident mean jack cause i was only testing above the ports. i went to my regular cycle shop and he said basicly the same thing. he told me to clean carbs put in some fresh plugs and let her rip. forgot to mention the retired honda tech said i prolly have a stator problem and that banshee was bad about stator problems burning one side up before the other. i am kinda lost at this point. its hard to ignore experience but cant put it over logic. my banshee will run perfect one day unless i get mad and sell it.

Your test is really only for trouble shooting. Same as a leak down test ( has a way different meaning when talking about 4 strokes). The test does not say what went wrong, It just tells what may be wrong at the moment. You are on the right track, stick with the site for getting info. If someone tells you the wrong thing here, they will be corrected. So you will get all the opinions you will need in one place.

 

Fuel/Air, Ignition, and Compression.

 

[Drturbodiesel]

Thanks guys for all the info. I apologize for making two posts on the same basic topic I will try to fix that on computer tommorow. My phone version is different. As far as my problem goes I plan to clean carbs sync carbs if nec and idle air mixture. I will then throw in a new set of plugs and retest. I will report my findings.

[Burt Reynolds]

Hello fellow banshee owners. I'm a new member first post. I got a 05 bone stock doesent look like engine has ever been into. I noticed that right cyl was spitting and sputtering at times in lower to mid range. Idles fine pulls hard thro upper rpm. I decided to check compression before I started messing with fuel spark etc. Found left cyl to have 130 right 112 cold. It will finally build 120 after a lot of kicks. Anyways it almost winter would it hurt to run it the rest of this fall or am I risking more sever engine damage? Also are 05 cylinders lined or can they be bored ? Thanks

 

Your honda tech has sort of a point,honda/yamaha 2 strokes are different brands but definitely the same principle. Your psi is to far out of wack. And you CAN go further than 80 over,you can go 100 over.Just make sure the machinist can do a straight bore!

A static psi test only tells you one side of the issue. But if you know what your engine SHOULD be running psi wise,then static psi is a good tool to use to keep an eye on your motor.

 

It may run for a while,but if you let it go to far you could turn your 250 top end job into 500+ complete rebuild. Ive seen people let their motors go to long and have pistons shatter and Completely ruin the entire bottom and top end.

Edited September 14, 2011 by Burt Reynolds

[Drturbodiesel]

Your honda tech has sort of a point,honda/yamaha 2 strokes are different brands but definitely the same principle. Your psi is to far out of wack. And you CAN go further than 80 over,you can go 100 over.Just make sure the machinist can do a straight bore!

A static psi test only tells you one side of the issue. But if you know what your engine SHOULD be running psi wise,then static psi is a good tool to use to keep an eye on your motor.

 

It may run for a while,but if you let it go to far you could turn your 250 top end job into 500+ complete rebuild. Ive seen people let their motors go to long and have pistons shatter and Completely ruin the entire bottom and top end.

 

im glad you see the logic in what i have going on. today makes a week i have had this machine so thats why i dont have any data to compare to recent tests. when previous owner bought it two years ago before he took it away to where it was till i got it i recall the spark plug boot on the good side was defective and or missing maybe leaving the right side to do most all the work and maybe thats why its weak now who knows.. also crappy air filter seal cage to box had maybe been partially briched and injested some dust. anyway i will get her to run even one way or another i would just about bet anything this is the same top end that and everything else that it was built from yamaha with so its prolly about time to rebuild. anyway thanks to all the mixed replies.

[Burt Reynolds]

im glad you see the logic in what i have going on. today makes a week i have had this machine so thats why i dont have any data to compare to recent tests. when previous owner bought it two years ago before he took it away to where it was till i got it i recall the spark plug boot on the good side was defective and or missing maybe leaving the right side to do most all the work and maybe thats why its weak now who knows.. also crappy air filter seal cage to box had maybe been partially briched and injested some dust. anyway i will get her to run even one way or another i would just about bet anything this is the same top end that and everything else that it was built from yamaha with so its prolly about time to rebuild. anyway thanks to all the mixed replies.

 

 

The key point for me here is,one a bone stock motor,or a ported 4mil drag stroker,9 psi or more difference in the cylinders means somethings up,so the static psi did give you and answer.Even when banshee motors get really worn out,the psi can still be within 5. EVen if your motor is supposed to have 150 per side and your down to where you are,there is still a big difference between the 2

Edited September 15, 2011 by Burt Reynolds

[LS3 Machine]

The bike is now 6 years old. That means it's been ridden for 6 or 7 years. Definitely sounds like the one side is not doing so well. I would consider coming up with a minor rebuild budget. What I would do if i was in your shoes:

 

Budget around 400 bucks: Get new pistons, have the cylinders bored by a forum vendor that will sell you the pistons, get new carb boots (they are 7 years old), upgrade to pod filters, clean and rejet the carbs, new plugs, and sync. (check the reed condition while you are in there, as they may need replacing)

 

Around 700 bucks: Add Cylinder port job from the forum vendor.

 

1000 bucks: Add Cool Head and domes.

 

Does our bike have stock exhaust?

 

 

Good Luck and keep us posted!