CR125 Keeps Eating Pistons

chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo
Edited Date/Time 10/20/2013 7:57am
Help. My CR125 was running ok all summer until I the bike and I went down going around a turn. the bike revved for 5-7 seconds before I could shut it off. The bike was laying on it's side. When I stood the bike back up and tried to start it, it had no compression. I got it home and took the head off. The piston had a hole in it and the Cylinder wall was trashed and the cylinder head was trashed. I also noticed the power exhaust valves (RC valves) were "stuck" in the full open position, from carbon buildup. So the bike was running this way for likely many months or longer. I bought a new cylinder jug, head, piston kit (standard 54mm), power exhaust (RC Valves), and gasket kit. Put it all back together with the piston installed per instructions and so on. Started it up. Did a break in procedure (ran for 10 minutes at idle, then shut it down to cool off). did this 2 or 3 times. Took the bike out for a ride up and down my neighborhood streets. It ran ok, but I could tell something was wrong. It had low end power but mid and high rpm range it ran poorly. Then it happended. The bike died out at mid to high rpm in 3rd gear. Had to walk it home about 1/2 mile. Took it apart. The top of the piston was damaged and the head was damaged. Cylinder walls were ok, power exhaust (RC valves) were ok.

photo piston-2.jpg

photo piston-4.jpg

photo piston-1.jpg

photo piston-5.jpg



WHY IS THIS HAPPENING?



A couple of things you need to know:



1.when I put the motor back together and went to start it up (with all new parts) I noticed the compression was low. I did not take a reading, but by kickstarting it, I noticed it was much lower than it was since I owned it. This concerned me very much, but this was my first 2-stroke rebuild and I thought it might be normal for a new piston/cylinder install prior to break in.
2.blows lots of smoke - but it always did and ran fine before
3.i did not check, or replace the Reed Valve - ever!
4.the piston (Wiseco standard) was indeed installed correctly (had an arrow to indicate which way to install)
5.i used a torque wrench for all cylinder and head bolts/nuts
6.the radiator was full and the water pump appeared to be working because the hoses were getting warm when I was running it during the break in (sitting on the stand idling)
7.I did not check or even think about the "bottom end" Never looked at or touched or inspected any of that.
8.running 32:1 mixture - standard 87 octane gas (normally works fine)
9.carb has been rebuilt by me recently and is good, has standard jetting and settings. Float level is good.
10.running standard spark plug
11.the power exhaust valves (new) appear to be installed and working properly but I don't know for sure. I can move them by hand with the bike off by pushing/pulling the control rod from the governor assembly. There is also a possibility that I did not install the power valve assembly correctly. There are c-clips, washers, a couple of range limiters and a spring that all go together on the end of the rod. I'm 75% sure I did it right, but not 100%. I compared it to photos I took and assembly diagrams and it seems to be right, but I'm not sure.
12. the bike year is 2000.

SEE ATTACHED PHOTOS OF THE LATEST PISTON DISASTER.


thanks for reading this and thanks for your help. Lee
|
mx5471
Profile picture for user mx5471
Posts
986
Joined
7/10/2008
Location
AL US
mx5471 10/13/2013 9:25am
10/13/2013 9:25am
Everything sure looks brand new. I suspect there's a piece of metal floating around in there, possibly from the old piston. Did you just replace the top end without splitting the cases? A piece could have been laying in the crankcase and got sucked up into the combustion chamber. That would be my guess.
xnationalwrench 10/13/2013 10:02am
10/13/2013 10:02am
mx5471 wrote:
Everything sure looks brand new. I suspect there's a piece of metal floating around in there, possibly from the old piston. Did you just replace the...
Everything sure looks brand new. I suspect there's a piece of metal floating around in there, possibly from the old piston. Did you just replace the top end without splitting the cases? A piece could have been laying in the crankcase and got sucked up into the combustion chamber. That would be my guess.
You never mentioned the crankshaft, I have seen the same thing when the rod bearing (big end) failing, but if you did not either flush or disassemble (split the cases) you were asking for problems.
Mxcrayz
Profile picture for user Mxcrayz
Posts
12
Joined
10/13/2013
Location
US
Mxcrayz 10/13/2013 1:13pm
10/13/2013 1:13pm
I agree, I think a piece of the old piston got down into the crankcase. The rod bearing probably needs to be replaced too.
project racer 10/13/2013 2:33pm
10/13/2013 2:33pm Edited Date/Time 10/13/2013 2:39pm
All of the above ^^^. With this being the second round of stray metal littering the engine, main bearings ,seals, and a rod kit would be in order along with another top end assembly. Usually any stray metal will come right up within a few seconds run time. Surprised it ran as long as it did.

On a closer look, some of those marks look very close to the size of circlip wire diameter.

The Shop

See All »
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 10/13/2013 3:10pm
10/13/2013 3:10pm
I also have to add that there is most likely a bad crank bearing or piston clip causing most of the issues. I would also add that the marks above the exhaust port look like the piston was attempting to seize at the exhaust bridge. Was an OEM piston put in or was that an after market unit? Looks like a forged piston in photos. In either case it looks like maybe the piston was not prepped with oil holes in it's side for the lubrication of the exhaust port bridge.
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/13/2013 6:11pm
10/13/2013 6:11pm
Paw Paw 271 wrote:
I also have to add that there is most likely a bad crank bearing or piston clip causing most of the issues. I would also add...
I also have to add that there is most likely a bad crank bearing or piston clip causing most of the issues. I would also add that the marks above the exhaust port look like the piston was attempting to seize at the exhaust bridge. Was an OEM piston put in or was that an after market unit? Looks like a forged piston in photos. In either case it looks like maybe the piston was not prepped with oil holes in it's side for the lubrication of the exhaust port bridge.
guys

thanks so much for your help. I agree the crankcase has to be cleaned up, there is likely metal pieces in there from the first piston that blew up, and I never cleaned out the crankcase. Having said that, I am not a bike mechanic. I am a "jack of all trades" and pretty handy and have built V8 car engines, but never pulled apart a dirt bike crankcase. Is this something I can do myself or am I getting in over my head here? I can buy a nice working used bike for about $900, or spend hundreds of dollars rebuilding mine and hope I don't screw it up.

Is this something I should tackle or just sell the bike as is and get another used one. I consider myself a good mechanic but I am not a trained experienced 2-stroke bike mechanic. I have just basic tools. I do have a complete service manual and that would help me. I looked at it and the job looks pretty big and complex.

?????
xnationalwrench 10/13/2013 7:25pm
10/13/2013 7:25pm Edited Date/Time 10/13/2013 7:28pm
Don't let it over whelm you, 2strokes themselves are pretty simple and you don't have to mess with the gearbox or clutch. You can split the cases with simple hand tools except you will need a flywheel puller and a case splitting tool (or fab it) and some of the tool kits came with the puller. Take your time and you can even tske pictures at each step. Once you get the crankshaft out you will have 2 choices to buy a new crankshaft or a rod kit and have a local shop to install it and balance it. Actually the more you disassembly the lest it should cost if you decide to take it to a shop This is just my opinion but unless you csn't find new parts I would stay away from used parts because the fuse is already lite being used. If you have rebuilt a V-8 engine a 2 stroke will ne easy with the trusty service manual.
Jakes Dad
Profile picture for user Jakes Dad
Posts
1865
Joined
6/22/2009
Location
Brooksville, FL US
Jakes Dad 10/14/2013 3:23am
10/14/2013 3:23am
Give Brent a call at TDC 2 Stroke Performance he's up I 90 form you about 45 minutes in Poplar Grove. I'm sure he'd help you get it apart, you'll need to re-machine the head and that's something he can do for you there. 815-261-6907

www.tdc2strokeperformance.com
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 10/14/2013 5:38am
10/14/2013 5:38am
You have been given good info here, so why have you now posted this same exact item in another forum just this morning?
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/14/2013 5:50am
10/14/2013 5:50am
Paw Paw 271 wrote:
You have been given good info here, so why have you now posted this same exact item in another forum just this morning?
I'm afraid I don't understand your question. I posted the same question in 3 different website forums so as to get the maximum number of responses from which to read, thus providing me with the best chances at finding what may have caused this problem and how best to fix it. Is there a problem with that? Last time I checked this is a free country and I can say and do as I please as long as I follow the rules and don't hurt anyone. Is there a "forum etiquette" that says you can only make a post in 1 forum or you will be banished and from the first forum to where the thread was introduced?
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 10/14/2013 2:48pm
10/14/2013 2:48pm
Look I can understand posting in more than one place if the info is not coming or seems off base, but you have been given good info and then still persist asking the same question when you have the answers. In the amount of time you have spent in posting in so many places, you could have pulled the engine down and found the problem by now.
Yes, it is a "free country" so you can also expect the "free advice" to end when the mouth gets out of shape as well!
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/14/2013 8:12pm
10/14/2013 8:12pm
Paw Paw 271 wrote:
Look I can understand posting in more than one place if the info is not coming or seems off base, but you have been given good...
Look I can understand posting in more than one place if the info is not coming or seems off base, but you have been given good info and then still persist asking the same question when you have the answers. In the amount of time you have spent in posting in so many places, you could have pulled the engine down and found the problem by now.
Yes, it is a "free country" so you can also expect the "free advice" to end when the mouth gets out of shape as well!
who made you the forum boss? stay out of my business jerkass. i decide where and when I will post threads. I decide when I no longer need further information about a thread that I started. That's not for you to decide. Who the hell do you think you are telling people when their personal posting and subsequent responses should stop, and how many forums they should be posting the same question to? Let me guess, you're a mall cop who couldn't make it as a real cop right? so you come on these forums like your some kind of "forum cop" thinking you can boss people around and tell people where, when, and for how long a thread should last. Get a life loser. Mind your own damn business and don't reply to a thread if all you're going to do is bitch about why the same question got posted on another forum. If you have nothing to offer to assist the author of the thread, then pass it up and go on to the next one - don't bitch and complain about someone's posting. If you don't like the song, change the channel. 1st amendment jerkass.
Jakes Dad
Profile picture for user Jakes Dad
Posts
1865
Joined
6/22/2009
Location
Brooksville, FL US
Jakes Dad 10/15/2013 3:44am
10/15/2013 3:44am
Go see Brent and ignore the forum police.
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 10/15/2013 6:12am
10/15/2013 6:12am
Paw Paw 271 wrote:
Look I can understand posting in more than one place if the info is not coming or seems off base, but you have been given good...
Look I can understand posting in more than one place if the info is not coming or seems off base, but you have been given good info and then still persist asking the same question when you have the answers. In the amount of time you have spent in posting in so many places, you could have pulled the engine down and found the problem by now.
Yes, it is a "free country" so you can also expect the "free advice" to end when the mouth gets out of shape as well!
chevywaldo wrote:
who made you the forum boss? stay out of my business jerkass. i decide where and when I will post threads. I decide when I no...
who made you the forum boss? stay out of my business jerkass. i decide where and when I will post threads. I decide when I no longer need further information about a thread that I started. That's not for you to decide. Who the hell do you think you are telling people when their personal posting and subsequent responses should stop, and how many forums they should be posting the same question to? Let me guess, you're a mall cop who couldn't make it as a real cop right? so you come on these forums like your some kind of "forum cop" thinking you can boss people around and tell people where, when, and for how long a thread should last. Get a life loser. Mind your own damn business and don't reply to a thread if all you're going to do is bitch about why the same question got posted on another forum. If you have nothing to offer to assist the author of the thread, then pass it up and go on to the next one - don't bitch and complain about someone's posting. If you don't like the song, change the channel. 1st amendment jerkass.
Look no one made me in charge of anything. You ask for free advice and help and it was freely give from folks here with many years of experience. Do you use it, no, you just keep posting the same question and photos on other forums after you already had the answers.
I can only speak for myself in telling you, you were given very good info and help by me and others and have chosen to ignore it and become a complete foul mouth low life. I would bet that if the answers were costing you money then there would have only been " one and done". I have only been working on the bikes from about 1968, so what do I know?

Let's face it...You put together a "time bomb" and it let go and now all you want to do is cry about it and see if someone will make you feel better about it. Well.......Get over it and let the knowledge base help you instead of acting like a baby!

Have a nice day!
MOTODAD422
Profile picture for user MOTODAD422
Posts
430
Joined
9/26/2008
Location
Easton, PA US
MOTODAD422 10/15/2013 10:34am
10/15/2013 10:34am
You need to use 91 octane or greater,using 87 won't cut it. It's probably causing pre-ignition or detonation,adding more heat and subsequent engine failure. Looking at the photos your current condition was caused by a stray piece of piston material.
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/15/2013 10:56am
10/15/2013 10:56am
Paw Paw 271 wrote:
Look I can understand posting in more than one place if the info is not coming or seems off base, but you have been given good...
Look I can understand posting in more than one place if the info is not coming or seems off base, but you have been given good info and then still persist asking the same question when you have the answers. In the amount of time you have spent in posting in so many places, you could have pulled the engine down and found the problem by now.
Yes, it is a "free country" so you can also expect the "free advice" to end when the mouth gets out of shape as well!
chevywaldo wrote:
who made you the forum boss? stay out of my business jerkass. i decide where and when I will post threads. I decide when I no...
who made you the forum boss? stay out of my business jerkass. i decide where and when I will post threads. I decide when I no longer need further information about a thread that I started. That's not for you to decide. Who the hell do you think you are telling people when their personal posting and subsequent responses should stop, and how many forums they should be posting the same question to? Let me guess, you're a mall cop who couldn't make it as a real cop right? so you come on these forums like your some kind of "forum cop" thinking you can boss people around and tell people where, when, and for how long a thread should last. Get a life loser. Mind your own damn business and don't reply to a thread if all you're going to do is bitch about why the same question got posted on another forum. If you have nothing to offer to assist the author of the thread, then pass it up and go on to the next one - don't bitch and complain about someone's posting. If you don't like the song, change the channel. 1st amendment jerkass.
Paw Paw 271 wrote:
Look no one made me in charge of anything. You ask for free advice and help and it was freely give from folks here with many...
Look no one made me in charge of anything. You ask for free advice and help and it was freely give from folks here with many years of experience. Do you use it, no, you just keep posting the same question and photos on other forums after you already had the answers.
I can only speak for myself in telling you, you were given very good info and help by me and others and have chosen to ignore it and become a complete foul mouth low life. I would bet that if the answers were costing you money then there would have only been " one and done". I have only been working on the bikes from about 1968, so what do I know?

Let's face it...You put together a "time bomb" and it let go and now all you want to do is cry about it and see if someone will make you feel better about it. Well.......Get over it and let the knowledge base help you instead of acting like a baby!

Have a nice day!
would you please just leave me alone and go far far away somewhere. Oh and by the way, you said you saw my posting in another forum, which means that you also visit other forums. According to you that's a "no-no". You should be ashamed of yourself and banished from the internet. You know the rules................1 forum per citizen..........Its in the Constitution.
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/15/2013 11:10am
10/15/2013 11:10am
MOTODAD422 wrote:
You need to use 91 octane or greater,using 87 won't cut it. It's probably causing pre-ignition or detonation,adding more heat and subsequent engine failure. Looking at...
You need to use 91 octane or greater,using 87 won't cut it. It's probably causing pre-ignition or detonation,adding more heat and subsequent engine failure. Looking at the photos your current condition was caused by a stray piece of piston material.
appreciate that bit of information. Thanks. I run high octane in my high compression street car, why not do it in the dirt bike? Can't hurt right?

What are your thoughts on the "low compression" after the rebuild? Like I said, new wiseco piston and ring (end gap correct) new cylinder, new cylinder head, new gaskets, proper torque settings. When I did the kickstart process, it was very easy to do, compared to the compression prior to my top end rebuild. Why would that be? I would have thought the compression would have been higher.
project racer 10/15/2013 12:20pm
10/15/2013 12:20pm
Lots of variables as to why cranking pressure may have changed. Wiseco rings take a bit more run time to break in and seal than OEM. The bike did not even survive a hour or so run time. Piston height could vary from OEM vs Wiseco. Aftermarket gaskets could be a bit thicker than OEM.

Just curious, what made you go with the Wiseco ?

Pit Row

See All »
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/15/2013 12:31pm
10/15/2013 12:31pm
project racer wrote:
Lots of variables as to why cranking pressure may have changed. Wiseco rings take a bit more run time to break in and seal than OEM...
Lots of variables as to why cranking pressure may have changed. Wiseco rings take a bit more run time to break in and seal than OEM. The bike did not even survive a hour or so run time. Piston height could vary from OEM vs Wiseco. Aftermarket gaskets could be a bit thicker than OEM.

Just curious, what made you go with the Wiseco ?
Ok, I understand what you are saying, but it seems strange that even if the ring (1) is not "broke in" and if the gasket was another .001" thicker that compression would be that noticeably different, but it must be the case. The Reed Valve would not be suspect would it? If that didn't work the bike wouldn't have run at all.

Regarding the Wiseco piston. I chose that because it seems what lots of people use where I ride and I've always known of them since I was a kid. I thought it was considered an upgrade compared to OEM pistons. Was I wrong? It seems like there are only 3 or 4 piston manufactures out there and Wiseco seems very popular. (namura, wiseco, pro-x, Honda) ?
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 10/15/2013 12:55pm
10/15/2013 12:55pm
chevywaldo wrote:
who made you the forum boss? stay out of my business jerkass. i decide where and when I will post threads. I decide when I no...
who made you the forum boss? stay out of my business jerkass. i decide where and when I will post threads. I decide when I no longer need further information about a thread that I started. That's not for you to decide. Who the hell do you think you are telling people when their personal posting and subsequent responses should stop, and how many forums they should be posting the same question to? Let me guess, you're a mall cop who couldn't make it as a real cop right? so you come on these forums like your some kind of "forum cop" thinking you can boss people around and tell people where, when, and for how long a thread should last. Get a life loser. Mind your own damn business and don't reply to a thread if all you're going to do is bitch about why the same question got posted on another forum. If you have nothing to offer to assist the author of the thread, then pass it up and go on to the next one - don't bitch and complain about someone's posting. If you don't like the song, change the channel. 1st amendment jerkass.
Paw Paw 271 wrote:
Look no one made me in charge of anything. You ask for free advice and help and it was freely give from folks here with many...
Look no one made me in charge of anything. You ask for free advice and help and it was freely give from folks here with many years of experience. Do you use it, no, you just keep posting the same question and photos on other forums after you already had the answers.
I can only speak for myself in telling you, you were given very good info and help by me and others and have chosen to ignore it and become a complete foul mouth low life. I would bet that if the answers were costing you money then there would have only been " one and done". I have only been working on the bikes from about 1968, so what do I know?

Let's face it...You put together a "time bomb" and it let go and now all you want to do is cry about it and see if someone will make you feel better about it. Well.......Get over it and let the knowledge base help you instead of acting like a baby!

Have a nice day!
chevywaldo wrote:
would you please just leave me alone and go far far away somewhere. Oh and by the way, you said you saw my posting in another...
would you please just leave me alone and go far far away somewhere. Oh and by the way, you said you saw my posting in another forum, which means that you also visit other forums. According to you that's a "no-no". You should be ashamed of yourself and banished from the internet. You know the rules................1 forum per citizen..........Its in the Constitution.
Unless you clean out the crank cavity and drill the proper lubrication holes in the piston at the exhaust bridge, you will just blow up again.
Enough said !
CamP
Profile picture for user CamP
Posts
6828
Joined
8/16/2006
Location
Colleyville, TX US
CamP 10/15/2013 1:00pm
10/15/2013 1:00pm Edited Date/Time 10/15/2013 1:01pm
Crank/rod bearing failure...

Wiseco pistons are junk, but didn't cause this damage.
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/15/2013 1:12pm
10/15/2013 1:12pm
Paw Paw 271 wrote:
Look no one made me in charge of anything. You ask for free advice and help and it was freely give from folks here with many...
Look no one made me in charge of anything. You ask for free advice and help and it was freely give from folks here with many years of experience. Do you use it, no, you just keep posting the same question and photos on other forums after you already had the answers.
I can only speak for myself in telling you, you were given very good info and help by me and others and have chosen to ignore it and become a complete foul mouth low life. I would bet that if the answers were costing you money then there would have only been " one and done". I have only been working on the bikes from about 1968, so what do I know?

Let's face it...You put together a "time bomb" and it let go and now all you want to do is cry about it and see if someone will make you feel better about it. Well.......Get over it and let the knowledge base help you instead of acting like a baby!

Have a nice day!
chevywaldo wrote:
would you please just leave me alone and go far far away somewhere. Oh and by the way, you said you saw my posting in another...
would you please just leave me alone and go far far away somewhere. Oh and by the way, you said you saw my posting in another forum, which means that you also visit other forums. According to you that's a "no-no". You should be ashamed of yourself and banished from the internet. You know the rules................1 forum per citizen..........Its in the Constitution.
Paw Paw 271 wrote:
Unless you clean out the crank cavity and drill the proper lubrication holes in the piston at the exhaust bridge, you will just blow up again...
Unless you clean out the crank cavity and drill the proper lubrication holes in the piston at the exhaust bridge, you will just blow up again.
Enough said !
Ok - enough of the bashing each other. I'm done and you probably are as well. I guess I have to apologize if I crossed the line. Having said that. The new piston that I installed did indeed have (2) lubrication holes in it, on the exhaust side, and a skirt opening hole on the other side. I made sure of that - it came from Wiseco that way. Just like factory OEM. With regards to cleaning out the crank cavity, I totally agree it has to be done - I'm just afraid of doing it and screwing it up. Probably a hundred or more parts in there, and even with a service manual I feel I will miss something in the reassembly process and have to start all over with the motor, when I should be out riding. Same thing happened when I put my chevy 454 back together and drove it. It worked great for a few hours until the oil pickup tube fell out of the oil pump - no oil pressure. I had to pull the entire motor out to fix it. Don't want to do that again. I am actually considering selling the bike as is, informing the buyer that the motor needs work, and try to get $500 for the whole bike. I can buy another nice used good running CR125 (year 2000-2003) for about $900-1100, and not have to do any work, and not have to put any money in rebuilding the existing crankcase and lower end, and not take a chance on screwing it up.

I would love to keep the bike and tear the crankcase apart and rebuild it, but I need to know that I have a "working bike - ready to ride" and not one that's always being worked on because I messed something up in the motor.
kevingent55
Profile picture for user kevingent55
Posts
155
Joined
9/20/2010
Location
Reno, NV US
kevingent55 10/15/2013 1:35pm
10/15/2013 1:35pm
Please check the reeds before you fire up the new engine, you'll be glad you did.
chevywaldo
Profile picture for user chevywaldo
Posts
157
Joined
10/12/2013
Location
Roselle, IL US
chevywaldo 10/15/2013 1:41pm
10/15/2013 1:41pm
kevingent55 wrote:
Please check the reeds before you fire up the new engine, you'll be glad you did.
what problems have you experienced with Reeds? I know it's basically a check valve. Lets air/fuel mixture in, blocks air/fuel from escaping crankcase. What problems (other than it being stuck open) would a bad reed cause?
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 10/15/2013 1:57pm
10/15/2013 1:57pm
Look, it has not been my intent to bash you in any way, as I can see that you in fact did put a lot of money in the engine only to have it fail due to a mistake or for taking something for granted. You did purchase good quality parts for the job.To fix it you will again spend a lot of money plus do more work.
If you don't feel like you can do that or don't feel like you have the ability take the engine down that far to fix it correctly, then selling it may be the answer.
The correct fix is not brain surgery, but it does require attention to every detail.
I will be glad to help you in any way I can, but your service manual has most of the info in it for the job, including the tools needed for the job.
JM485
Profile picture for user JM485
Posts
5409
Joined
10/1/2013
Location
Davis, CA US
JM485 10/15/2013 2:16pm
10/15/2013 2:16pm
CamP wrote:
Crank/rod bearing failure...

Wiseco pistons are junk, but didn't cause this damage.
What's wrong with Wiseco? I have been using them for years and have never had an issue with them. I don't know what happened to your piston but I have never had any issues.
project racer 10/15/2013 3:11pm
10/15/2013 3:11pm
Buying any used bike is a roll of the dice. And a used 125, even more so. Chances are the news-d one will need some attention after a bit of riding, especially if it has seen some time or you yourself ride hard. It's a 125. Turns a lot of RPM. RPM = wear.

There are several reputable engine rebuilders out there. Not sure if Eric Gore is still doing them, but Jakes Dad mentioned another in an earlier post. I would bet even someone in your area could help you out.

Motorcycles break. No guarantees on a used sickle or a newly rebuilt engine.

That's a choice you have to make.
project racer 10/15/2013 3:14pm
10/15/2013 3:14pm
CamP wrote:
Crank/rod bearing failure...

Wiseco pistons are junk, but didn't cause this damage.
Hope he does not buy one of their cranks if the decision is to fix the bike.
CamP
Profile picture for user CamP
Posts
6828
Joined
8/16/2006
Location
Colleyville, TX US
CamP 10/15/2013 3:51pm
10/15/2013 3:51pm
CamP wrote:
Crank/rod bearing failure...

Wiseco pistons are junk, but didn't cause this damage.
project racer wrote:
Hope he does not buy one of their cranks if the decision is to fix the bike.
No joke. Wiseco cranks are beyond crap.
CamP
Profile picture for user CamP
Posts
6828
Joined
8/16/2006
Location
Colleyville, TX US
CamP 10/15/2013 3:53pm
10/15/2013 3:53pm
CamP wrote:
Crank/rod bearing failure...

Wiseco pistons are junk, but didn't cause this damage.
JM485 wrote:
What's wrong with Wiseco? I have been using them for years and have never had an issue with them. I don't know what happened to your...
What's wrong with Wiseco? I have been using them for years and have never had an issue with them. I don't know what happened to your piston but I have never had any issues.
They expand and seize on the exhaust bridge. Their band-aid fix is to let the consumer drill holes in their brand new piston. They also have crappy quality control and their sizing is all over the place.

Post a reply to: CR125 Keeps Eating Pistons