endofitall9 Posted September 7, 2006 Report Share Posted September 7, 2006 (edited) okok so the local shop argued with me that i cant just replace 1 piston without throwing the balance of my crank off so terefore I should replace them both, 5 rides on a motor and the bore is .40 over. Anybody know if there is any truth to this or would it be safe to just replace 1 side? thanks Josh Edited September 7, 2006 by endofitall9 Quote Link to comment Share on other sites More sharing options...
jakehopt Posted September 7, 2006 Report Share Posted September 7, 2006 I've heard that too, I'm not exactly sure whether there is any truth to it tho... Quote Link to comment Share on other sites More sharing options...
fun_on_the_sand Posted September 7, 2006 Report Share Posted September 7, 2006 I assume that if you want to change one piston you are going to go at least one size larger because the wear is on both cylinder and piston. So if you have one piston larger than the other one that makes one piston havier than the other one therefore you are out of balance Quote Link to comment Share on other sites More sharing options...
endofitall9 Posted September 7, 2006 Author Report Share Posted September 7, 2006 nono noone said about boring or what not like stated above 5 rides on the motor 2 tanks of gas i still have th hone marks in the cylinders from where eric gorr done his work so needless to say the cylinders will be staying at .40 over. just need to know if i can just replace the side that leaned out and burnt a hole in the piston without having to replace the other side that is practically brandnew. the local shop says i have to replace them both but i disagree as long as you get the same size piston. I need an expert, loco,rippen, bigred350x? someone that is reputable. Quote Link to comment Share on other sites More sharing options...
BigRed350x Posted September 7, 2006 Report Share Posted September 7, 2006 If you aren't going to bore it out, I would say sure... go ahead and slap a new piston in there. shouldn't hurt anything. Although you will probably have one side with higher compression than the other. I would just replace both pistons if I were going to do it. Quote Link to comment Share on other sites More sharing options...
endofitall9 Posted September 7, 2006 Author Report Share Posted September 7, 2006 yeah i figured that but also thought that since it was fairey new i would just re-ring the old piston and check it out... the shop said that i aboslutely could not do this but they don't know anything about banshees everything that know is basically from what i tell them....... Quote Link to comment Share on other sites More sharing options...
csrmel Posted September 7, 2006 Report Share Posted September 7, 2006 ive seen people do that kind of stuff on car engines and it worked out ok, but car engines are not as wild as a banshee. the thing i would be concerned about is any chunks of melted piston down in the case. i would hate to see you put new parts in this thing, fire it up and spin a bearing because a molten glob of aluminum had squeezed into a bearing where you couldnt see it. Quote Link to comment Share on other sites More sharing options...
Ducman Posted September 7, 2006 Report Share Posted September 7, 2006 Yeah, be sure to clean out the case, make sure the pieces of piston are gone. As far as the new piston goes, as long as you buy the same exact brand and make of piston that is being used they should weigh within a certain tollerance of each other anyway. I wouldn't even change the rings on the good side as long as it didn't get leaned out or burnt at all. Unless of coarse you have to remove that cylinder to help clean out the case, then you may as well throw on a new set of rings. Be sure to take it easy and break in the new piston and rings. If you do keep the same rings on the remaining good piston remember that the side with the new piston and rings will run differently than the existing side for a while untill it has a few heat cycles. Remember to heat cycle the motor a couple of times and let it cool all the way down before riding it after installing new rings. Quote Link to comment Share on other sites More sharing options...
easttexasbanshee Posted September 7, 2006 Report Share Posted September 7, 2006 Yes, make sure you get the exact same piston like the other one thats in there. As far as ballance of the pistons, I always ballance my pistons. Even a brand new set of weisco pistons can be 10-15 grams difference in them. Get a scale like used in a science lab, or you can probley buy one for like 15-20 bucks at a hobbie shop and then get a die grinder and very very slowly take small portions of metal out of the under side of the piston. I have always done this.....has worked well on several sets of pistons for me. You just have to be careful, but its easy. Quote Link to comment Share on other sites More sharing options...
endofitall9 Posted September 7, 2006 Author Report Share Posted September 7, 2006 yeah the cases are already split did that the day it happend, as far as shit getting in the crank. I didn't see nothing most of the piston went out the exhaust. i still got to flush it out though also the cylinders dont have a mark on them I noticed it was runing wierd so i shut it out but the damage was done, I've had 3 cranks go in the last year so if this vitos crank goes then its bye bye banshee. i run wiseco prolites .40 are all wisecos that are .40 over the same? the ones in it are 513mo6500. If it get to where i have to weigh the pistons to make sure then the hell with that i'll just replace both it will just take longer, tight on the cash right now and i hate to see a practically brandnew piston go to waste. thanks for the help! Josh Quote Link to comment Share on other sites More sharing options...
easttexasbanshee Posted September 7, 2006 Report Share Posted September 7, 2006 yeah the cases are already split did that the day it happend, as far as shit getting in the crank. I didn't see nothing most of the piston went out the exhaust. i still got to flush it out though also the cylinders dont have a mark on them I noticed it was runing wierd so i shut it out but the damage was done, I've had 3 cranks go in the last year so if this vitos crank goes then its bye bye banshee. i run wiseco prolites .40 are all wisecos that are .40 over the same? the ones in it are 513mo6500. If it get to where i have to weigh the pistons to make sure then the hell with that i'll just replace both it will just take longer, tight on the cash right now and i hate to see a practically brandnew piston go to waste. thanks for the help! Josh Weighing and balancing the pistons is easy, you don't have to do it, thats just getting pretty nit picky about it, im sure you would be fine if you just got another piston to mach the one you already have. And yes weisco makes more than one kind of piston for a banshee. Quote Link to comment Share on other sites More sharing options...
endofitall9 Posted September 7, 2006 Author Report Share Posted September 7, 2006 it kind of sucks..I would like to speak to Eric Gorr about this but considering.....hes gone! When He done my cylinders he said they were bored specifically for wiseco part# 513MO6500, so I guess thats the piston I need, I know wiseco makes different types of pistons I just didn't know if they make a different series of the same size bore of pistons. I'll probably end of calling wiseco myself and see what they have to say about the different weights of the pistons. my main priority is to not screw this crank up. I love me banshee but I love the girl more and if I have to drop $400 on another crank considering this one is brandnew then its bye bye banshee and a headache from yelling. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted September 7, 2006 Report Share Posted September 7, 2006 It's about 20 bucks for rings. it's about 75 bucks for a new piston... Is it worth saving 50 bucks to wonder? I'd re-hone each cylinder, buy the pistons, re-mic and check for clearances, and replace both Pistons.... (Aside from cleaning out the cases as everyone mentioned as well).. Quote Link to comment Share on other sites More sharing options...
endofitall9 Posted September 7, 2006 Author Report Share Posted September 7, 2006 yeah usually, I say...If you have to think about what to do, do what you think is right, that would be replacing both pistons, here in wv its just close to the shitty weather and was wanting to ride before it hit guess im down till next spring. thanks for all the info guys Quote Link to comment Share on other sites More sharing options...
yyz Posted September 7, 2006 Report Share Posted September 7, 2006 i had a similar problem with a 4 corner score during breakin... mine were .020 over wiseco prolites... called wiseco and they said their tolerances are very good weight-wise and that i could just replace one piston with no problems... so i did and have had no problems... that was about 6 months ago... banshee pistons from wiseco are not sold in balanced sets... according to wiseco all of their banshee pistons are within a half gram weight-wise... i would just make sure you mic the new piston and set the appropriate clearance when you re-hone the cylinder... i would of course put new rings in as well and clean everything well too... you could also call wiseco and see what they say as well... yyz Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.